2009:009

M A S T E R ' S T H E S I S

Measuring the Availability at the Sawmilland the Capacity at the Planing Mill

at SCA Timber Rundvik Sawmill

Svetlana Stolyarova

Luleå University of Technology

Master Thesis, Continuation Courses Wood Technology

Department of Skellefteå CampusDivision of Wood Science and Technology

2009:009 - ISSN: 1653-0187 - ISRN: LTU-PB-EX--09/009--SE

Measuring the availability at the sawmill and the capacity at the planing mill at SCA Timber Rundvik sawmill

Svetlana Stolyarova

Master of Science Programme in Wood TechnologyThe Department of Wood Technology at Luleå University in Skellefteå

2008-04-15

I

Abstract

This master thesis was done at SCA Rundvik sawmill.Rundvik sawmill belongs to SCA group. It is produced 231,000 m³ and with the share of developed timber is 61 %.

One of two goals with this master thesis is to measure the availability at the sawmill more detailed.It means to start to count a stop as a downtime in the production after 10 seconds instead of 1 minute. And it is to make more stop codes over the sawline to show the sectionswhere the stops appear often. It was not done any analyzes of the stops reasons or made any suggestions how to avoid them. The conclusion does not give any solutions how to increase the availability.The measuring time was 127 hours and the availability gotten during the measuring is 65%.Stops were started to be registered after 10 seconds since they occurred. The sorting of the stops were done. Stops from 10 seconds to 1 minute were sorted like short stops and gave about 2,3 hour per 1 productive week.The distribution of the stops shows the area of the sawing house where the problems exist. These areas are the saw in feed, the sawline, the green sorting, the stick stacker, the chips and sawdust area. The share of the total stop time is viewed around these areas. A brief analyze of the stick stacker area has been done. For the sawline, the use of degree was measured - 76% - and zones (machines) were pointed out if they are in need of an improvement to increase the productivity.

The second goal of the work was to check the flow at the planning mill, at the specificsection from the in feed to the planer. The assignment at the planer mill is to look at one special product that gives the lack of boards to the planer.According to the data from SCA, the planer needs 200/3,7 ≈ 54 piece/minute in average. The mean value (pieces/minute) that goes really through the planer is 23 pieces/minute.Capacity losses and areas with problems in this section were estimated.

II

Preface

This master thesis was done from December 2007 to May 2008.I want to say thanks to SCA Timber, Rundvik sawmill for the possibility to make my master thesis in the company.

I want to thank specially:

Sören Edmark (technical director) initiated to this master thesis.

Sten - Olov Andersson (sawmill manager) for his trust in this work.

Lars – Erik Jönsson (supervisor /production manager) for his support and trust in this work.

Peter Henriksson (supervisor /production manager) for his supervising and help.

Alf Eriksson (planing mill manager) for the help and support with data.

Kent Jonsson (production optimizer) for the help and support with the measuring equipment.

Micael Öhman (examiner/supervisor, LTU) for his support and help during the work for the master thesis.

Also I want to give big and great thanks to all operators, especially Johnny Grahn and Peter Eriksson, for the support during my master thesis work and thanks to the maintenance staff for their help.

Svetlana Stolyarova

Rundvik 2008-04-15

III

Index

Abstract IPreface IIIndex III

1. Introduction 11.1 Rundvik sawmill 11.2 Background to the master thesis 21.3 Mission 21.4 Goal 21.5 Delimitation 3

2. Presentation of the sawmill and the planing mill 42.1 Saw process 5

2.1.1 Saw in feed 52.1.2 Sawline 82.1.3 Green sorting 112.1.4 Pockets 132.1.5 Stick stacker 13

2.2 Planing process 142.2.1 Tilt area 142.2.2 Elevator area 142.2.3 Operator area 152.2.4 Area between the operator area and the planer 152.2.5 Briefly about the planer and what happens after the planer 16

3. Methods and materials 173.1 Sawmill 17

3.1.1 Measuring and calculating the availability for the saw house 173.1.2 Present situation at the sawmill 203.1.3 Use of degree for the sawline 203.1.4 Example of calculating the availability and the use of degree for the saw house 21

3.2 Stick stacker 223.2.1 Measuring the use of degree of the stick stacker area 22

3.3 Planing mill 243.4 Easy calculating in excel 253.5 Measuring equipment 25

IV

4. Theory 264.1 Value stream mapping 264.2 Some useful Lean thinking 274.3 Calculating the availability 294.4 Calculating the use of degree 304.5 The importance to have a short time until it start to register a stop 314.6 Statistical evaluation method 324.7 Bottleneck 334.8 Best practice 334.9 SMED (Single Minute Exchange of Die) 34

5. Results 355.1 Present situation availability for the sawmill 355.2 New measured availability 375.3 Use of degree for the sawline 435.4 Stick stacker 465.5 Planing mill 485.6 Calculating in excel for the first section of the planing mill 51

6. Discussions and conclusions 536.1 Availability in the saw house 53

6.1.1 Compare the present situation and the new measured availability 53

6.1.2 New measured availability 536.2 Use of degree in the sawline 546.3 Stick stacker 556.4 First section in the planing mill 566.5 Use for the calculating in excel for the planing mill 576.6 Achievements of the project 57

7. Suggestions for the continues work 597.1 Sawmill 597.2 Planing mill 59

Reference 60

Appendix 62Appendix 1. Layout Rundvik sawmill 63Appendix 2. Data for the present situation at the sawmill 64Appendix 3. Data for the stick stacker 66Appendix 4. Data for the planing mill 67Appendix 5. Layout Rundvik planing mill first section 69

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1. Introduction

1.1 Rundvik sawmill

Rundvik sawmill is situated in a village called Rundvik near E4, between Umeå and Örnsköldsvik in Västerbotten.

ProductionThe production is nordic spruce. At Rundviks sawmill they produce 231,000 m³ timber of that it is 99,000 m³ further processed. Share of developed timber is 61 %.

CertificationRundvik Sawmill is certified in accordance with ISO 9001:2000, 14001:2004 and FSC Chain of Custody (Forest Stewardship Council).

Site plan

Picture 1. Shows the site plan for Rundvik sawmill.

EmployeesToday they are 78 employees and 26 contractors.

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1.2 Background to the master thesis

At the sawmill the availability is measured in a rough way. In the future it is wanted to be more detailed. A more detailed measuring will give information to take the right decision to do some technical investments.

At the planer mill an investment will be made. It is needed to have data before to change the equipment and to see the effect of the investment. The assignment at the planer mill is to look at one special product that gives the lack of boards to the planer.

1.3 Mission

One of two missions with this master thesis is to make it more detailed about measuring the availability at the sawmill. It means to reduce time before man start to count the downtimesduring the sawing process. And make more stop codes over the sawline so it will point out where the stops exist.

The second mission will be to look at the flow between the in feed at the planer mill to the planer (just a little section of the whole planing mill).

1.4 Goals

For the sawline:

1. Measure the uptime and the downtime for the availability.2. Make conclusions for the data according to the availability.- Define how many short stops (from 10s to 1min) exist and summary value of them.- Show stops distribution around the sections including what values short and long stops have for every section.- Analyze the distribution of the stops around the areas in accordance to the sawing pattern.- Show the distribution of the stops inside of the sawline.3. Calculate the use of degree for the sawline.4. Make conclusions for the old availability data.- Show stops distribution around the sections including what values short and long stops have for every section.- Compare this old data with the new results.

For the planing mill:

1. Find the mean value for the capacity (pieces/minute) on the section between the infeed (tilt) for boards at the planing mill to the planer.2. Estimate capacity losses in this section.

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1.5 Delimitation

At the sawmill, it is just to look from the area saw in feed to the area where the stick stacker is.

The conclusion will not give any solutions how to increase the availability. Any analyzes of stops reasons will be not done or made any suggestions to avoid them.

It will just be to look for the zone between the in feed (tilt) for boards at the planing mill to the planer.

The conclusion will not give any cost estimate. Status report during the work will only be oral at the leading board meetings. The study excludes to look at the quality and mechanics damage of the planks and

sideboards.

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2. Presentation of the sawmill and the planing mill

Rundviks sawmill belongs to SCA Timber together with seven more sawmills. The raw material that is transported to Rundviks sawmill will pass some stations at the sawmill area before it goes to the customer.The stations that they will pass are log sorting, saw house, drying kilns, grading plant and the planing mill.

At the log sorting the logs are divided into classes according the top diameter and length. The sorting consists of 64 bins.The sorting at this station is made by an impartial organisation called VMF.

At the saw house area there are many sections where barks, planks, boards, chips and sawdust are produced.The bark, chips and the sawdust are the rest products. And the plank and board are the main products.The bark is taken away at the saw in feed area. The sawline cuts out the planks and boards and also gives the material for the rest products like chips and sawdust.At the green sorting they make the first adjustments for the planks and boards and sort them in different pockets. The sorting is according to the quality, length and dimensions.Finally at the saw house it is the stick stacker section where they make the packages for the drying kilns.

The drying process takes a lot of time. It takes between 2 to 20 days. The difference in time depends on which dimension and the moisture content that are needed to be achieved.The boards of the same dimension and moisture content are collected together in the same kiln.

After drying the planks and the boards go either to the grading plant or the planing mill.At the grading plant they grade every plank and board piece by piece. When the grading is finished, packages are made to be delivered to the customers. At the planing mill the planks and boards are planned and then graded and made package for delivering to the customers. The process that is observed in this project consists of the saw house and the part before the planer in the planing mill.

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2.1 Saw processThis part is included in this project and it will be more described what happens in each section atthe saw house.The sections are:

Saw in feed Sawline Green sorting planks and boards Pockets Stick stacker

2.1.1 Saw in feedThe first step is to get the log from the log truck, see picture 2.

Picture 2. Shows a timber truck and the beginning of the saw in feed.

After that the logs are divided one by one in a step feeder. After the step feeder it goes on a longitudinal conveyor through a scanner.

When the scanner has given the information of the shape of the log, it is decided in which way the log should turn when it comes to the log turner, see picture 3.

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Picture 3. Shows the log turner.

After the turner the log goes on a longitudinal conveyor through the debarking machine, see picture 4.

Picture 4. Shows the debarking machine.

The debarking machine is cleaning the logs from the bark. After the debarking machine the logsgo on a cross way conveyor to the butt reducer, see picture 5.

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Picture 5. Shows the butt reducer.

After the butt reducer logs go on a longitudinal conveyor to a cross way conveyor and finally to the step feeder that puts them to the sawline.This step is necessary to get a round shape of the butt end of the logs. If this is not taken away, it can cause a problem for the optimizing the saw process. The problem can be that the turner will not turn as much as it is needed. If it has happened it is expected that the yield out of the log perhaps will be lower than a predicted value.

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2.1.2 SawlineThe sawline is a full automatically optimizing profiler sawline from Ari, see picture 6.In the line it is optimizing the sideboards individually for each boards and it is also a curve sawing line.

Picture 6. Shows a sawline from Ari.

In the picture 7, 8 and 9 there is the function of the machines at the sawline. The beginning of the saw process is started in the picture 7 to the left end then it moves to the right through the picture 8 and 9. So the finally step in the sawline will be the circle saw that cut out the centre planks/boards.

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First four steps in the sawline, see picture 7:

1. The first step is the 2-D scanner (Stockmätning/mätram). The scanner gives the information for every saw machine in the sawline. This information makes every log to be optimized through the saw process.

2. Second step is the turner (Rundvridning). The turner make the log turn to the optimized position.

3. Third step is the precilog measuring (Precilogmätning). This measuring is done if the log should move cross way. The log moves depending on the optimizing from the scanner and the precilog measuring equipment.

4. Fourth step is a conveyor. This conveyor can move a little bit crossway (left or right) at the same time it puts the log in the longitudinal direction.

Picture 7. Shows the first four steps in the sawline.

Next four steps in the sawline (the steps after picture 7), see picture 8:

5. Fifth step is the first cutting. This machine cuts out two plane surfaces on the log and turns in to a block with two plane surfaces.

6. Sixth step is measuring (Blekesmätning) for optimizing the profile cutting in step seven.7. Seventh step is a cutter that cuts out a profile of a board on the block. 8. Eighth step is a circle saw that cuts out the first pair of sideboards.

Picture 8. Shows next four steps in the sawline.

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Last six steps in the sawline, see picture 9:Make a notice in the picture 9, it just shows 5 steps. There is one more machine after step twelve, so step thirteen does not exist in picture 9.

9. Ninth step is measuring (Blekesmätning) for optimizing the profile cutting in step ten.10. Tenth step is cutting out the final profile from the block.11. Eleventh step is a block turner.12. Twelfth step is to cut away the last existing round surface on the block.13. Thirteenth step is to cut out sideboards.14. Fourteenth step is to divide the finally block into centre boards/planks.

Picture 9. Shows the finally five steps in the sawline.

After this procedure the centreboards/planks and sideboards are divided into two flows. Thecentre boards/planks go to the green sorting for planks. The sideboards move to the green sorting for sideboards.

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2.1.3 Green sorting

Green sorting centreboards/planks:Green sorting for planks just go on a crossway conveyor, see picture 10 to the pockets, see picture 11. Some sorting can be done when it is different dimensions of the centre planks. Thenthey go on the upper cross way conveyor, see in picture 10. There is possible to sort the planks so the planks of same dimension fall in the same pocket, see picture 11.

Picture 10. Shows the cross way conveyor for the planks just after the sawline.

Picture 11. Shows the planks falling into a pocket.

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Green sorting sideboards:Green sorting for boards goes on a crossway conveyor, see picture 12 to the pockets. The sorting to the pockets is according of dimension, quality and length. This process is done with scanning measuring equipment for grading boards. The dimension, length and amount of wane of the board can be measured with the equipment. Just before the pockets it is a trimmer which is cutting the boards to the right length according to some parameters that is set in the measuring equipment.

Picture 12. Shows the green sorting for the sideboards.

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2.1.4 PocketsDepending on the quality, dimension and length the boards are sorted in one of the 25 pockets see picture 13. The planks side consists of 6 pockets and the sorting is based on the dimensions.Pockets make the storage after the green sorting. When a pocket is full it can be opened and pieces/package drives to the stick stacker.

Picture 13. Shows the pockets.

2.1.5 Stick stackerThe last step is the stick stacker area.When a pocket at the sorting area is full the operator automatically or manually empties the pocket.The planks and boards from each pocket are put together to a package ready for the drying kiln. These packages consist of the same dimension of boards or planks.To make the packages it is also necessary to have a flow of sticks.The main purpose of the sticks is to make a gap between every layer of boards or planks in the packages. These gaps help the drying process.The planks and boards go on the crossway conveyors from the pockets to the package making.The flow is stopped periodically to make a gap between every layer so a package can be made. It also puts the boards piece by piece so they can go in longitudinal way. When the boards go in the longitudinal way, they are separated to opposite directions. So every first board goes more to the right and the every second board is moved to the opposite left direction. That makes the packages wider and is necessary for the further process at the sawmill.Picture 14 is a view of the finished package with visible gaps that the sticks make.

Picture 14. Shows a final package from the stick stacker section.

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2.2 Planing processThis part is included in this project. Further it will be more described what happens in each zone in the section before the planer in the planing mill. What happens after the planer will be overviewed briefly.The zones of the studied section are:

Tilt area Elevator area Operator area Area between operator area and the planer

2.2.1 Tilt areaThis area consists of the intake for packages, the tilt and two cross way conveyors after the tilt, see picture 15.

Picture 15. Shows the tilt area.

2.2.2 Elevator areaElevator is viewed on the picture 16. The elevator function is to divide the boards piece by piece to the cross way conveyor before the feeder to the operator area.

Picture 16. Shows a common elevator.

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2.2.3 Operator areaThe operator area consists of the few small cross way belt conveyors and separators. See picture 17.This area makes big gaps between the boards, so the operator can check piece by piece.

Picture17. Shows the operator area.

2.2.4 Area between the operator area and the planer In this area it is just crossways conveyors until the feeder to the planer, see picture 18.

Picture 18. Shows the area just before the planer.

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2.2.5 Briefly about the planer and what happens after the planer

Feeder fills a planer to make the surfaces of the boards smooth. After the planer a sorting machine locates – “Wood Eye”. There the boards are sorted according to quality and “Wood Eye” sends information about the locations of defects to a marking machine. All the boards go through the marking device that marks them based on the information from “Wood Eye”. The marking is done with an invisible ink.Then it is located a scanner device which recognizes the marks on the boards and sendsinformation to a separator. The separator turns some boards to the second floor conveyors if it is necessary. The boards with satisfied quality and length continue to follow first floor conveyors to the package assembling section. Before this section the label machine and trimmer exist. Labels are tagged only to boards for USA market. The finished packages follow on rolls-conveyors to the package packing section.The boards with defects move on conveyors of second floor to “OPTICUT 350”- cutting device. Defects are cut depending on marks of the invisible ink and the length module. The boards passing “OPTICUT 350” have usually two groups of quality: “A” and “B”. The boards and the wastes after cutting go the same conveyor to the waste pusher first and then to the pushers that separate boards according to their quality.The boards of quality “B” turn to another conveyors and then to the package assembling sections. Boards of quality “A” move to the last pusher and are separated there in accordance to their lengths to the different package assembling sections. Before the packaging boards are tagged with labels if they keep going to USA market. All finished packages go to the package packing section.

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3. Methods and materials

A computer will be used for putting together all data. A software excel and a usual calculator will be used for calculating. For measuring the availability and use of the degree, the mobile measuring equipment

will be used.( Description of the mobile measuring equipment is done further on, see chapter 3.5 )

3.1 Sawmill

3.1.1 Measuring and calculating the availability for the saw house

Calculating the availability is like a share of the real production time and the planned production time.

100 timeproductionPlanned

time))stop Unplanned timeup(Set - timeproduction(Planned(%)

tyAvailabili

Planned production timePlanned stop timeSet up timeUnplanned stop time

= Total available time - Planned stop time.= Planned break time + Maintenance time.= Time for pattern changing.= Stops that appear during planned production time.

Measuring point is between the 2D-scanner and the log turner in the sawline, see layout (Layout Rundvik sawmill) in appendix 1 or between steps 1 and 2 in the picture 7. This point was chosen for the measuring point to check the presence of logs flow in the beginning of sawline to keep production in this section during planned time.

Sawing patterns will be noticed during the measuring period to look if some correlation between availability of sawline and a saw pattern exist. Because of short time of measuring it is impossible to make reliable analysis of availability in accordance to every saw pattern. Like it was observed the most repeated patterns consist of from 3 to 10 boards as a total amount out from one log. That is why all sawing patterns will be dividedin two groups in accordance to amount of the boards. First group will include all sawing pattern that give 1-5 boards, second group includes sawing pattern that give more than 5 boards. So, the conclusion of stops distribution around the areas will be done for twogroups of sawing patterns.

Stop in the flow will be recognized like a downtime after 10 seconds. Downtimes are sorted in different groups (short and long) in accordance to their lengths and these are:

Stops between 10 second to 60 seconds. Stops from 1 minute and more.

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Stops sorting in two groups is good to define the amount of chronic stops (Definition for chronic stops is done in chapter 4.5) Besides, to define summary value of short stops (from 10s to 1min) is a requirement from a company side. The stop codes have different colours in the layout, which you see in appendix 1. For making it easy between the operator and the master theses worker, it was suggested to colour codes on a paper.The sawline is divided into small zones adapted to the layout of the line, see appendix 1. These zones will also be used to look for the use of degree.

Stop codes for the availability are (see layout in appendix 1):

Planned stops:

1. Planned stops. Include breaks, night stops and planned maintenance.

Unplanned stops:

2. Saw in feed and debarking area. It includes everything before the first conveyor in the sawline: debarking machine and every handling for the bark after the debarking.

3. Chips and sawdust area. Includes conveyors handling chips and sawdust.

4. Green sorting planks area. Includes the sideway conveyors for the planks after the lengthway conveyors of the sawline and the pockets of the green sorting.

5. Green sorting boards area. Includes the sideway conveyors for the boards after the lengthway conveyors of the sawline and the pockets of the green sorting.

6. Stick stacker area. Includes the conveyors from under the pockets to the forklift truck.

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Unplanned stop codes for the sawline (see layout in appendix 1):

7. Log conveyor + Scanner.

8. Log turner.

9. Centring machine KSI-7 + conveyor between KSI-7 and SKR-700.

10. Plane reducer SKR-700.

11. Conveyor between SKR-700 and SBF-2.

12. Profile cutter SBF-2.

13. Sideboards cutter SBS-2.

14. Sideboards conveyors (chain conveyors + band conveyors).

15. Conveyor between SBS-2 and BBF-4.

16. Profile cutter BBF-4 + conveyor between BBF-4 and BV-1.

17. Block turner BV-1.

18. Conveyor with holder between BV-1and BKR-700.

19. Wane cutter BKR-700 + conveyor between BKR-700 and DS-72.

20. Sideboards cutter DS-72.

21. Conveyor between DS-72 and DS-72+1.

22. Planks cutter DS-72+1.

23. Band conveyors after DS-72+1.

24. Stop for pattern changing. Includes time from a stop beginning to a moment of the planned stable flow (that means that flow goes with planned speed and dimensions of the sawn products are correct).

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3.1.2 Present situation at the sawmill

Old data for the year 2007 is viewed in the appendix 2. The data gives the present situation for the availability. The calculation is made like it is explained in the chapter 3.1.1.

A difference between the old and new data is that the stops were registered like downtimes during 2007 only if they were longer than 1 minute.

The definition for long and short stops was also done in 2007.

Short stops are between 1 to 15 minutes.Long stops are longer than 15 minutes.

3.1.3 Use of degree for the sawline

The use of degree for the sawline will be defined like:

100 timeoperativeAvailable

timeprocessedReal(%)degreeofUse

Available operative timeReal processed timeDowntime

= Real processed time + Downtime in the saw section.= Time when a flow of logs exists in the sawline.= Stops are caused by disruptions occurred in saw section

(stops that have stop codes numbers 7-25).

Important: Stops will be not calculated like a downtime for the sawline if they are caused by disruptions and stops in other sections. So, the stops, defined by stop codes numbers from 1 to 6, will be not counted like downtime for sawline.The use of degree for the sawline will be calculated like this:

Take the data from the measuring the availability. The downtime for the saw in feed-, green sorting (plank and board area)-, stick stacker

and the chips and sawdust area will now be excluded from the data. Left is the time for the sawline that includes: real processed time and available operative

time. Sawing patterns will be noticed to look if some correlation between use of degree for the

sawline and a saw pattern exist. Like in case of availability analysis, all sawing patterns will be divided in two groups. First group includes all patterns that give less than 5, or 5 pieces out from one log. Second group includes all patterns that give more than 5 pieces out from one log.

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3.1.4 Example of calculating the availability and the use of degree for the saw house

Take up an example of calculating the availability and the use of degree for the saw house.

Conditions during 1 week: Planned production time to 112h = (112*60) = 6720 minutes. Stop in Saw in feed and debarking area with 400 minutes. Stop in Sawline with 1000 minutes. Stop in Chips and sawdust area with 100 minutes. Stop in Green sorting planks area with 115 minutes. Stop in Green sorting board’s area with 400 minutes. Stop in Stick stacker area with 250 minutes

The availability of the saw house:

%3,66100

6720

25040011510010004006720

The use of degree of the sawline is:

Planned production time to 112h = (112*60) = 6720 minutes. Time for the stops excluding the sawline is (400+100+115+400+250) = 1265 minutes. The time that it should be a flow in the sawline is (6720-1265) = 5455 minutes. Downtime in sawline was 1000 minutes, includes all types of stops.

So that gives:

Real processed time = 5455-1000 = 4455 minutes. Available operative time = (4455+1000) = 5455 minutes = Planned time – stops from

exterior sources = (6720-1265) = 5455 minutes.

Use of degree of the sawline is:

%7,811005455

4455

The availability will be 66,7 % and the use of degree will be 81,7 %.

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3.2 Stick stacker

3.2.1 Measuring the use of degree of the stick stacker area

The measuring equipments in this area are:

A stopwatch A note book

The measuring point is chosen at the separator because boards and planks are coming piece by piece there, see picture 19.

Picture 19. Shows the measuring point at the stick stacker area.

Calculating the use of degree at the stick stacker area:

100 timeoperativeAvailable

timeprocessedReal(%)degreeofUse

Real processed time

Available operative time

Downtime

= Time, when a flow exists in the measuring point in the stick stacker area.

= Real processed time + Downtime at the stick stacker area.

= Stops are caused at the stick stacker area.

Measuring point at the stick stacker

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Stop codes for the stick stacker area:

Stops are caused by disruptions in the other sections and will be excluded from downtime of the stick stacker area:

1. Lack of boards means that it is impossible to drive the stick stacker because of lack of planks and boards in the pockets.

2. Truck causes a stop when it does not take away the package in time.

. Stops are caused by disruptions in the stick stacker area. They will be included in downtime ofthe stick stacker area to calculate the use of degree for this area:

3. Boards area stops are caused by disruptions inside the stick stacker area.

4. Dimension marking is the stop where the paper marking is put on the package that showsdimensions of boards for every package.

5. Sticks area stop includes stops in the board flow because of the problems in the sticksarea. Sticks area starts from the truck puts sticks to the incoming conveyor until sticks are laid on a package.

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3.3 Planing mill

At the planing mill, it is just to look at one section. This section is from the in feed (tilt) for boards to the planer, see layout on appendix 5.

The given data from SCA are:

The dimension to look at is 21*95 mm and the length of each board is 3,7 meters. Planer capacity is 200 meter/minute (maximum capacity is 350 meter/minutes).

It is important to check the flow of pieces/minute for the feeder that feeds the planer. According to the data from SCA, the planer needs 200/3,7 ≈ 54 piece/minute in average.

First, capacity of every area inside of the chosen section will be calculated in relation to real speeds of conveyors and existing gaps. Areas, where the capacity (pieces/minute) will be countedfor, are presented in the layout in the appendix 5:

1. Tilt area. 2. Elevator area.3. Operator area. 4. Feeder to the planer.

Second, it is to measure real capacity (pieces/minute through the planer) for the whole chosensection and estimate losses. Capacity losses are related to downtime at the measuring point. Measuring point is chosen at one-piece separator at the operator area.

All stop codes are done in relation to studied areas and are divided in two groups. First group includes stops that are caused by disruptions in the section that was studied.

Tilt Stick area Elevator Elevator conveyor (conveyor following the elevator) Operator area Operator conveyor(conveyors between operator area and the feeder) Feeder

Second group includes stops are caused by disruptions occurred in rest of the planing mill.

Planer Wood Eye Sorting area Cutter Package area Other (stops such ventilation and electricity problems in the planing mill)

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3.4 An easy calculating in the excel

An easy flow calculating will be made in the excel program just to visualize the flow in the first section in the planing mill.According to the given initial condition for the planer (see chapter 3.4), speeds, required to the tilt area, the elevator, conveyors, can be calculated.For making this flow calculation, followed devices will be used:

A computer and the excel program. A measuring tape to get gaps in average between boards on the conveyors. A measuring device for speed of the conveyors.

3.5 Measuring equipment

Given mobile measuring equipment is used to register and collect data from the sawing process. It is also able to monitor data and analyze data in GantBrowser software. The measuring equipment consists of:

Hardware:

Inductive sensor.

Computer/Server

Monitor.

Cable

Software:

GantBrowser.

Sensor: Feeds the server with a flow at some measuring point.Signals from sensor go through the cable to the server.

Server: Stores the data for the measuring and handle software GantBrowser.

Monitor: Makes it possible to visualize the data.

Cable: Makes the connection between the sensor and the server.

GantBrowser: Makes the data to be analyzed and view the graphical presentation of stops and flow continuously together with a time scale. It also represents the list of stop codes that is used to notice the reasons of the stops.

From this mobile equipment it is possible to get an excel-file with collecting data.

26

4. Theory

4.1 Value stream mapping

According to (Sayer at al 2007 e), the value stream is the flow of materials and information through a process to deliver a product or service to a customer. Value Stream Map is a graphical representation of how all the steps in any process line up to produce a product or service, and of the flow of information that triggers the process into action.Based on (Sayer at al 2007 a), Value Stream Maps are often hand drawn plots that describe a process from input of raw materials through to delivery of goods or services to the customer.The indentified customer at the end of a Value Stream Map may not be just the end customer who buys the finished product or service, but the customer may be another business or some other function within the same organization.

First, the current state of Value Stream Map is constructed – the way things are now.The process steps are timed and divided to value-added and non-value added. Second, the ideal Value Stream Map is constructed – the ideal process, where all steps are value–added steps.Next, improvement to refine the current state is conducted and Value Stream Map is updated to visualise the changes to the process. The improvement should constantly move the process in the direction of the ideal state.

Value Stream Map of the sawing process will be done from saw in feed like input to stick stacker as output of products. The layout of the sawline will be used for Value Stream Map graphical presentation (see Layout Rundvik sawmill in appendix 1) . Every section or machine of this layout represents a separate step of the process. And every section is used to be value-added step when the production flow exists through this section. If it is no flow through the chosen section, that means that during this downtime, no value is added to the process.

27

4.2 Some useful Lean thinking

This chapter is a presentation of some thoughtful words which Lean thinking production is based on.

Kaizen:

“Kaizen” is an improvement.

Dennis (2007 a), says that “kaizen” is a small incremental improvement. “Kaizen” activity should involve everyone regardless of position.

According to (Sayer et al 2007 e), “kaizen” is incremental continuous improvement that increases the effectiveness of an activity to produce more value with less waste.

Gemba:

“Gemba” is there the product has there operation to become the finally product.

According to (Dennis 2007 a) “gemba” is the real place or a specific place. Usually it means the shop floor and other areas where work is done.

Based on (Imai 1997 a), Japanese word “gemba” is meaning “real place” – now is adapted in management terminology to mean the “workplace” – or that place where value is added. In manufacturing, it usually refers to the shop floor.

In accordance to (Sayer et al 2007 e) “gemba” is place where the action occurs.

Go to gemba:

This usually means go to the shop floor.

Imai (1997 a) says that “go to gemba” is the first principle of gemba kaizen. This is a reminder that whenever an abnormality occurs, or whenever a manager wishes to know the current state of operations, he or she should “go to gemba” right away, since “gemba” is a source of all information.

GTS:

According to (Dennis 2007 a) GTS is Grasp The Situation; the heart of PDCA cycle.

28

Muda:

“Muda” means waste.

According to (Imai 1997 a) the Japanese word “muda” is meaning “waste” which when applied to management of the workplace, refers to a wide range of non-value-adding activities. In gemba there are only two types of activities: value adding and non-value adding activities.

According to (Sayer et al 2007 e) “muda” is any activity that consumes resources, but creates no value. “Muda” is categorized in two forms: “Type-1 muda” is necessary for the process, but non-value-added; “type-2 muda” is both unnecessary and non-value-added.

Genchi genbutsu:

Based on (Dennis 2007 a) “genchi genbutsu” is translated like go and see; go to the real place and see what is actually happening.

According to (Sayer et al 2007 d and e) “genchi genbutsu” means “go and see”. It is also written that one of the fundamentals of the Toyota way is called “genchi genbutsu”. In short, this means “go to the actual scene (genchi) and confirm the actual happenings or things (genbutsu)”.The power of “genchi genbutsu” is in the firsthand knowledge that you gain. It’s one thing to look at a report, see a bunch of numbers, and draw conclusions. It’s totally different experience to go to an area and see what the numbers mean.

Such methods like “Genchi genbutsu”, GTS and “Go to Gemba” will be used during this project in the way to observe the process and the reasons of downtime directly in the shop floor. Unplanned downtimes can be characterised like muda or non-value-adding activities.

29

4.3 Calculating the availability

According to (TPM for Supervisors 1992 a) the availability is defined like this:

100timeloading

downtime-timeloadingyAvailabilt

In this case, loading time is the daily (or, monthly) time available for operation minus all forms of scheduled stops – breaks in the production schedule, stops or routine maintenance, morning meeting, and so on.Downtime is the total time taken for unscheduled stops such as breakdowns, retooling and adjustment.Loading time minus downtime yields the operating time.Finally (TPM for Supervisors 1992 a) say that the availability tells us what percentage of the time equipment is actually running when we need it.

In this project the availability will be calculated in the way as described in chapter 3.2.1. and that is like this:

100 timeproductionPlanned

time))stop Unplanned timeup(Set - timeproduction(Planned(%)

tyAvailabili

Planned production timePlanned stop time Set up time Unplanned stop time

= Total available time - Planned stop time. = Planned break time + Maintenance time.= Time for pattern changing.= Stops that appear during planned production time.

Availability is one component to Overall Equipment Effectiveness (OEE) calculating.The other parts are Performance and Quality.According to (OEE for Operators 1999) OEE traditionally consists of Six Major Losses, and these are briefly described like this:

Availability:Downtime losses

Failures Setup time

Performance:Speed losses

Minor stops Reduced operating speed

Quality:Defect losses

Scrap and rework Startup loss

OEE will be calculated like this: OEE = Availability x Performance x Quality x 100 (%)

Example of OEE calculating: 0,66 x 0,80 x 0,85 x 100 = 44,9 %

30

4.4 Calculating the use of degree

According to (Ljungberg 2000 a) the definition for real use of degree is the quota between real process time and available operating time.

timeoperatingAvailable

timeprocessedRealdegreeofuseReal

Ljungberg (2000 a) says that the use of degree is measuring losses from small stops and idle running. Real use of degree means how big share of the available operating time is used.

In this project the use of degree will be defined like this:

100

) sections)otherallfortime Stoptime stop(Planned-timerunning(Total

sectionmeasuredintimeFlowdegreeofUse

Flow time in measured section:This means when a flow occurs where the measuring point exists.

Total running time:There is all time for the measuring period.

Planned stop time:This is a stop that is planned, for example breaks and maintenance work.

Stop time for all other sections:There are stops that occur in other sections and these stops time should not influence on the measured section.

31

4.5 The importance to have a short time until it start to register a stop

During working with measuring it is important to have a short time until starting to registry the stop time. Why it is important is that a production line can consist of many short stops. These stops are called chronic stops, and they occur very frequently and have a short stop time.It also exist stops called a sporadic stops. A sporadic stop is very difficult to predict when it will be happened, but it occurs not so often.According (Nord et al 1997) a sporadic stop is very obvious and very often really easy to repair. Most of time it is just to put the machine back to the current existing state. This stop occurs not so often and is haphazard and leads to long stops.The chronic stop is often shorter, but happens all the time. These stops are often hidden and are difficult to find. To estimate the chronic stop take a deep analyze to find the cause of these stops.Graphical plot of chronic and sporadic stops, see picture 20.

Picture 20. Shows a picture for chronic and sporadic looses, before and after improvement.

Here come some examples of both types of looses.

Sporadic looses Broken axle.

Broken gear wheel in a gearbox.

Chronic looses Put away sawdust/chips that interrupt

the process. Turn boards. Sticks that go wrong at stick stacker

section. A photocell need to be cleaned.

Stop intensity

Time

Sporadiclooses

Chroniclooses

Sporadiclooses

Before improvement After improvement

Improvement occur

Chronic looses

32

4.6 Statistical evaluation method

Pareto diagram shows a collected data in a very visible way. The biggest stop caused for the process points out easily in a vertical staple diagram. Usually man looks for some of the biggest staples to the left in the diagram, which will usually have a very big effect on the process.It is also possible to have the staple in horizontal position. When the staples are in a horizontal position so is the biggest stop cause highest up in the diagram.

According to (Dennis 2007 a) it is said that pareto diagram is a problem solving tool comprising a bar chart showing possible contributing factors in decreasing order.

According to (Sayer et al 2007 c and e) the pareto chart is explained like as a bar chart where the categories are presented in descending order of frequency. The pareto principle states 80 percentage of the data will fall in 20 percentage of the categories.

How Imai (Imai 1997 a) explain the pareto chart is: it is a graphical tool for ranking causes from the most significant to the least significant. It is based on the Pareto principle, first defined by J.M. Juran. This 80:20 principle suggests that 80 percentage of effect com from 20 percentage of the possible causes.

The pareto diagram is very often useful in the PDCA –circle to give the priority to stop causes in a process.

In this project the pareto diagram/chart will be vertical staples, see pictures 21 for example.

Example on a pareto diagram

0%5%

10%15%20%25%

stop c

ause

11

stop c

ause

7

stop c

ause

12

stop c

ause

10

stop c

ause

6

stop c

ause

13

stop c

ause

4

stop c

ause

9

stop c

ause

8

stop c

ause

2

stop c

ause

5

stop c

ause

1

stop c

ause

3

Causes

Per

cen

t

Picture 21. Shows a pareto diagram in percentage share.

33

4.7 BottleneckA bottleneck in a line is the machine or operation that has the slowest processing. According tothat you can say that this is machine or operation that makes less pieces/minutes in the whole line/process.

According to (Sayer et al 2007 b) the definition is: The bottleneck process is the process with the longest cycle time. In continue (Sayer et al 2007 e) it is explained a bottleneck like this: A process that constricts or limits the flow of overall process.

According to (Bicheno 2004) bottlenecks govern both throughput and inventory in a system. A plant’s output is the same as the bottleneck’s output and inventory should only be let into a factory at a rate that bottleneck is capable to handling. It is the bottleneck that should govern flow.

4.8 Best practice

Best practice is an improvement technique that goes in relation of what have been occurredreally. Take a sawline as a process line. The measured goal for the sawline is, for example, the availability. And this number is following up every week. After this measuring is done for some weeks, it is possible to see a best practice. The week that had the highest result for the availability is the best practice. With this result man knows what is possible to reach against the best practice; it means to make everybody to be better in their work.

According to (Ilsley 2000) the biggest benefit with best practice is that all of the common workers should be better and catch up to the best performers at the shop.

Best practice improvement tools are always in change because a new situation can occur, and it means the process line can be rebuilt in some way. If it happens it must be observed over the goal of the best practice that was done. The improvement tool can be changed or it is possible to continue with it, so even this improvement tool is always under constant improvement.

Best practice method can be applied to analyse the work at the stick stacker section.

34

4.9 SMED (Single Minute Exchange of Die)

Single minute exchange of die is a method to improve the set up time. One example of meaning can be improved the changing of equipment in the saw machines when changing from one to another sawing pattern occurs.

According to (Santos et al 2006 a) this improvement method developed by Shigeo Shingo in Japan between 1950 to the 1980s.With this methodology, it is possible to achieve good result without costly investments, which makes implementation an many factories an easy decision to make.So what is a set up process? Definition according (Santos et al 2006 a) is a setup process corresponds to the time required to go from the end of the last good part from one batch to when the first good part of the following batch is produced.

When a setup process occurs, it exists of two types of operations and they are external and internal setup.According (Santos et al 2006 a) it is described this operation like this:

Operation that can be carried out with the machine running and producing parts for the previous lot. Shingo called these types of activities external setup.

Operations that required the machine to be idle while they were performed, Shingo denoted those operations as internal setup.

According to (Santos et al 2006 a) SMED – method consists of four steps, and they are:

1. Preliminary stage. That means to study the current process for setup.2. Stage 1. Separating internal and external setup.3. Stage 2. Converting internal setup to external setup.4. Stage 3. Streamlining all aspects of the setup process.

A good thinking example from (Santos et al 2006 a) about SMED is:“For instance, when you are replacing the tires on your personal vehicle, what does it matter if it takes an hour to change all four tires? However, in car racing (Formula 1 or NASCAR), losing 15 seconds may have very catastrophic consequences for the driver’s success.”

Finally about SMED, it improves the availability and quality rate. According to (Santos et al 2006 a) they say SMED implementation improves the availability rate as well as the quality rate because SMED reduces all the setup process time.

35

5. Results

5.1 Present availability for the sawmill

During the weeks 1- 4 in the year of 2007, the dividing of stops is viewed on the figure 1. Downtime was registered like a short stop from 1 to 15 minutes, and the stops longer than 15 minutes were sorted as the long stops. These four weeks represent January of 2007, the most problematic month of saw production because of low temperatures.

Figure 1. Shows the availability, share of the total stop time around stop causes in the saw houseand the share between long and short stops for each stop cause during the weeks 1- 4 of 2007.

36

Results of the availability measure that was done during the weeks 1 – 48 of 2007, are shown on the figure 2. Downtime was registered like a short stop from 1 to 15 minutes, the stops longerthan 15 minutes were sorted as the long stops.

Figure 2. Shows the availability, share of the total stop time around stop causes in the saw house and the share between long and short stops for each stop cause during the weeks 1- 48 of 2007.

These two diagrams look the same but both of them are represented that the availability and distribution of the stops are obviously constant during the whole year of 2007. The results duringJanuary and the rest of the year 2007 are similar and do not depend much on the weather conditions.

37

5.2 New measured availability

The figure 3 gives the common picture for the weeks 4-6 of measuring in the beginning of 2008.

Figure 3. Shows the availability, share of the total stop time around stop causes in the saw house and the share between long and short stops for each stop cause during the weeks 4 – 6 of 2008. It also represents the use of degree for the sawline.

38

Par

eto

19,4

%

13,0

%

11,0

%

7,1%

6,5%

4,8%

4,5%

4,0%

3,7%

3,7%

3,1%

2,8%

2,6%

2,5%

2,3%

1,6%

1,3%

0,9%

0,9%

0,6%

0,5%

0,4%

0,3%

0,3%

0,3%

0,3%

0,2%

0,2%

0,2%

0,2%

0,1%

0,1%

0,1%

0,1%

0,1%

0,1%

0,1%

0,1%

0,1%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

5,0%

10,0

%

15,0

%

20,0

%

25,0

%

Saw in

feed an

d deb

arkin

g Lon

g

Stop fo

r pat

tern ch

angin

g Lon

g

DS-

72+1 L

ong

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acker

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g

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BF-2 L

ong

KSI-7 +

conve

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st Lon

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BBF-4+ co

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r Lon

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BKR-7

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KSI-7

+ co

nveyo

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Dia

gram

1. S

how

sth

e sh

are

of th

e to

tal s

top

tim

e be

twee

n al

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p co

des

used

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easu

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for

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labi

lity

of t

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aw

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ring

wee

ks 4

-6

of 2

008.

39

The figure 4 represents the common results of measuring the downtimes during weeks 4 – 6 of 2008 and for the first group of sawing patterns.The figure 5 shows the common share of downtimes during weeks 4 – 6 of 2008 and for the second group of sawing patterns.A definition for the pattern sorting was given in the chapter 3.1.1. First group includes all the patterns that give less than 5 or 5 pieces out from one log. Second group includes all the patterns that give more than 5 pieces out from one log.

Figure 4. Shows the availability, share of the total stop time around stop causes in the saw house, use of degree for the sawline and the share between long and short stops for each stop cause during weeks 4 – 6 of 2008.

40

Ava

ilab

ilit

y of

saw

mil

l (s

aw p

atte

rns

less

th

an 5

or

5 p

iece

s)

45,0

%

13,1

%

7,9%

6,0%

4,6%

4,2%

4,1%

2,0%

1,9%

1,7%

1,6%

1,5%

1,4%

0,8%

0,8%

0,7%

0,7%

0,6%

0,6%

0,3%

0,2%

0,1%

0,1%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

5,0%

10,0

%

15,0

%

20,0

%

25,0

%

30,0

%

35,0

%

40,0

%

45,0

%

50,0

%

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r pat

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g Lon

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g

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arkin

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+co

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r Lon

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r Lon

g

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+1 Shor

t

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st L

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Chips a

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ort

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gram

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how

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for

saw

ing

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erns

that

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e le

ss th

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or

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eces

out

from

one

log.

41

Figure 5. Shows the availability, share of the total stop time around stop causes in the saw house, use of degree for the sawline and the share between long and short stops for each stop cause during weeks 4 – 6 of 2008.

42

Ava

ilab

ilit

y of

saw

mil

l (s

aw p

atte

rns

mor

e th

an 5

pie

ces)

14,7

%14

,0%

12,3

%

8,1%

6,8%

5,7%

5,4%

4,6%

4,1%

3,6%

3,3%

3,2%

3,1%

2,0%

1,5%

1,2%

1,1%

0,7%

0,5%

0,4%

0,4%

0,4%

0,3%

0,3%

0,2%

0,2%

0,2%

0,2%

0,1%

0,1%

0,1%

0,1%

0,1%

0,1%

0,1%

0,1%

0,1%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

0,0%

5,0%

10,0

%

15,0

%

20,0

%

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feed an

d deb

arkin

g Lon

g

Stop fo

r pat

tern ch

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g Lon

g

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g

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acker

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g

Green

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ng Pla

nks Lon

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g

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conve

yor L

ong

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nd sawdu

st L

ong

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r Lon

g

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ong

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ong

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g

Green

sorti

ng Boa

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ong

Saw in

feed a

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g shor

t

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r Lon

g

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oard

s co

nvey

or L

ong

conve

yor a

fter D

S-72+

1 Lon

g

DS-72

+1 Shor

t

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yor a

fter D

S-72

Long

Stop fo

r pat

tern ch

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g sho

rt

BKR-700

+co

nveyo

r Shor

t

conve

yor a

fter D

S-72+

1 Shor

t

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yor a

fter S

BS-2 L

ong

SBS-2 S

hort

BV-1 L

ong

Log co

nveyo

r + sc

anner

Shor

t

Log tu

rner

Lon

g

Log tu

rner

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t

Green

sorti

ng Pla

nks Shor

t

Conve

yor w

ith h

older

Shor

t

SBF-2 S

hort

Side b

oard

s co

nvey

or S

hort

SKR 700 S

hort

BBF-4+ co

nveyo

r Shor

tDS-

72 S

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yor a

fter S

KR-7

00 L

ong

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yor a

fter D

S-72

Short

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fter S

BS-2 S

hort

BV-1 Sh

ort

Stick st

acker

Shor

t

Log co

nveyo

r + sc

anner

Lon

g

Green

sorti

ng Boa

rds S

hort

Conve

yor w

ith h

older

Lon

g

Conve

yor a

fter S

KR-7

00 S

hort

Chips a

nd sawdu

st S

hort

KSI-7

+ co

nveyo

r Shor

t

Dia

gram

3. S

how

sth

e sh

are

ofth

eto

tal s

top

tim

e be

twee

n al

lsto

p co

des

used

in th

e m

easu

ring

for

avai

labi

lity

of t

he

saw

hou

se d

urin

g w

eeks

4-

6 of

200

8 fo

r sa

win

g pa

tter

ns th

at g

ive

mor

eth

an 5

pie

ces

out f

rom

one

log.

43

5.3 Use of degree for the sawline

The diagram 4 views a share of the total stop occurred by disruptions only in the sawline. It is the average picture for all sawing patterns during weeks 4 – 6 of 2008.

Par

eto

for

Use

of

deg

ree

saw

lin

e

22,5

%

19,0

%

8,2%

7,8%

6,4%

6,3%

5,3%

4,8%

4,2%

2,8%

2,3%

1,6%

1,5%

1,1%

0,9%

0,7%

0,6%

0,5%

0,5%

0,5%

0,4%

0,4%

0,3%

0,3%

0,2%

0,2%

0,2%

0,1%

0,1%

0,1%

0,1%

0,1%

0,0%

0,0%

0,0%

0,0%

0,0%

5,0%

10,0

%

15,0

%

20,0

%

25,0

%

Stop fo

r pat

tern ch

angin

g Lon

g

DS-72

+1 Lon

gSBF-2

Lon

g

KSI-7 +

conve

yor L

ong

BBF-4+ co

nveyo

r Lon

gDS-

72 L

ong

SKR 700 L

ong

SBS-2 L

ong

Conve

yor a

fter D

S-72

Long

BKR-700

+co

nveyo

r Lon

g

Side b

oard

s co

nvey

or L

ong

conve

yor a

fter D

S-72+

1 Lon

g

DS-72

+1 Shor

t

Conve

yor w

ith h

older

Lon

g

BKR-700

+co

nveyo

r Shor

t

Stop fo

r pat

tern ch

angin

g sho

rt

Log co

nveyo

r + sc

anner

Shor

t

conve

yor a

fter D

S-72+

1 Shor

t

Conve

yor a

fter S

BS-2 L

ong

SBS-2 S

hort

Log tu

rner

Shor

t

Conve

yor w

ith h

older

Shor

t

BV-1 L

ong

Side b

oard

s co

nvey

or S

hort

Log tu

rner

Lon

g

SBF-2 S

hort

SKR 700 S

hort

Conve

yor a

fter S

BS-2 S

hort

BBF-4+ co

nveyo

r Shor

t

DS-72

Shor

t

Conve

yor a

fter S

KR-7

00 L

ong

Conve

yor a

fter D

S-72

Short

BV-1 Sh

ort

Log co

nveyo

r + sc

anner

Lon

g

Conve

yor a

fter S

KR-7

00 S

hort

KSI-7

+ co

nveyo

r Shor

t

Dia

gram

4. S

how

sth

e sh

are

ofth

eto

tal s

top

tim

ear

ound

the

stop

cod

es in

the

saw

sect

ion

duri

ng w

eeks

4

–6

of 2

008.

44

The diagram 5 presents a common picture of share of total stop occurred by disruptions only in the sawline and for the first group of sawing patterns. The patterns, that are less than 5 or 5 pieces out from a log, are included to the first group. A definition and a need for pattern sorting were given in the chapter 3.3.1.Measures are done during weeks 4 – 6 of 2008.

Use

of

degr

ee s

awli

ne (

saw

pat

tern

s le

ss t

han

5 o

r 5

piec

es)

30%

18%

14%

10%

5%4%

4%3%

3%2%

2%2%

1%1%

1%1%

0%0%

0%0%

0%0%

0%0%

0%0%

0%0%

0%0%

0%0%

0%0%

0%0%

0%5%10%

15%

20%

25%

30%

Conve

yor a

fter D

S-72

Long

Stop f

or pa

ttern

chan

ging

Lon

gDS-

72 L

ong

DS-72

+1 Lon

g

BKR-700

+co

nveyo

r Lon

g

Side b

oard

s co

nvey

or L

ong

BBF-4+ co

nveyo

r Lon

g

DS-72

+1 Shor

t

BKR-700

+co

nveyo

r Shor

t

Log co

nveyo

r + sc

anner

Shor

t

Conve

yor w

ith h

olde

r Sho

rt

Conve

yor w

ith h

olde

r Lon

g

Log tu

rner

Shor

t

Side b

oard

s co

nvey

or S

hort

Stop f

or pa

ttern

chan

ging

shor

t

Conve

yor a

fter S

BS-2 S

hort

SBS-2 S

hort

SKR 700 S

hort

SKR 700 L

ong

SBS-2 L

ong

SBF-2 S

hort

SBF-2 L

ong

Log tu

rner

Lon

g

Log co

nveyo

r + sc

anner

Lon

g

KSI-7 +

conve

yor L

ong

DS-72

Shor

t

Conve

yor a

fter S

KR-7

00 L

ong

Conve

yor a

fter S

KR-7

00 S

hort

Conve

yor a

fter S

BS-2 L

ong

conve

yor a

fter D

S-72+

1 Shor

t

conve

yor a

fter D

S-72+

1 Lon

g

Conve

yor a

fter D

S-72

Short

BV-1 Sh

ort

BV-1 L

ong

BBF-4+ co

nveyo

r Shor

t

KSI-7

+ co

nveyo

r Shor

t

Dia

gram

5. S

how

sth

e sh

are

ofth

eto

tal s

top

tim

ear

ound

the

stop

cod

es in

the

saw

line

duri

ng w

eeks

4 –

6 of

200

8 an

d fo

r th

e fi

rst g

roup

of s

awin

g pa

tter

ns p

roce

ssed

.

45

The diagram 6 gives a common picture of share of the total stop occurred by disruptions only in the sawline and for the second group of sawing patterns. Second group includes all patterns that give more than 5 pieces out from one log. Measures are done during weeks 4 – 6 of 2008.

Use

of

degr

ee s

awli

ne (

saw

pat

tern

s m

ore

than

5 p

iece

s)

23%

20%

9%9%

7%6%

5%5%

3%2%

2%1%

1%1%

1%1%

1%1%

0%0%

0%0%

0%0%

0%0%

0%0%

0%0%

0%0%

0%0%

0%0%

0%5%10%

15%

20%

25%

30%

Stop f

or pa

ttern

chan

ging

Lon

g

DS-72

+1 Lon

gSBF-2

Lon

g

KSI-7 +

conve

yor L

ong

BBF-4+ co

nveyo

r Lon

g

SKR 700 L

ong

SBS-2 L

ong

DS-72

Lon

g

BKR-700

+co

nveyo

r Lon

g

Side b

oard

s co

nvey

or L

ong

conve

yor a

fter D

S-72+

1 Lon

g

DS-72

+1 Shor

t

Conve

yor w

ith h

olde

r Lon

g

Conve

yor a

fter D

S-72

Long

Stop f

or pa

ttern

chan

ging

shor

t

BKR-700

+co

nveyo

r Shor

t

conve

yor a

fter D

S-72+

1 Shor

t

Conve

yor a

fter S

BS-2 L

ong

SBS-2 S

hort

BV-1 L

ong

Log co

nveyo

r + sc

anner

Shor

t

Log tu

rner

Lon

g

Log tu

rner

Shor

t

Conve

yor w

ith h

olde

r Sho

rt

SBF-2 S

hort

Side b

oard

s co

nvey

or S

hort

SKR 700 S

hort

BBF-4+ co

nveyo

r Shor

t

DS-72

Shor

t

Conve

yor a

fter S

KR-7

00 L

ong

Conve

yor a

fter D

S-72

Short

Conve

yor a

fter S

BS-2 S

hort

Log co

nveyo

r + sc

anner

Lon

g

Conve

yor a

fter S

KR-7

00 S

hort

BV-1 Sh

ort

KSI-7

+ co

nveyo

r Shor

t

Dia

gram

6. S

how

sth

e sh

are

ofth

eto

tal s

top

tim

ear

ound

the

stop

cod

es in

the

saw

sect

ion

duri

ng

wee

ks 4

–6

of 2

008

and

for

the

seco

nd g

roup

of s

awin

g pa

tter

n pr

oces

sed.

46

5.4 Stick stacker

The results from the stick stacker section are viewed in the diagrams 7 and 8. The diagram 8represents the whole picture for the section. The total stop time consists of stops are caused byboth of disruptions inside the stick stacker section and in the other sections. The stop causes were defined in the chapter 3.2.1.The total time of measure is 23 hours. This time does not include planned breaks like lunch and planned maintenance.The total stop time is 11,4 hours.

Pareto stick stacker the whole picture

32,0%29,8%

19,6%

9,7%8,6%

0,4%0%

5%

10%

15%

20%

25%

30%

35%

Lack ofboards

Boards area New package Sticks area Dimensionmarking

Truck

Stop causes

Per

cen

t

Diagram 7. Shows the share of the total stop time included all the stop reasons inside and out ofthe stick stacker section.

47

The diagram 8 shows the share of the total stop occurred by stop reasons which are only inside of stick stacker section. The stops are caused only by disruptions in the stick stacker area will be used for the calculation of the use of degree. The total time of measure is 23 hours. This time does not include planned breaks like lunch and planned maintenance.The total stop time is 7,7 hours.

Diagram stop causes at stick stacker

44,0%

29,0%

14,3%12,6%

0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

Boards area New package Sticks area Dimension marking

Stop causes

Per

cen

t

Diagram 8. Shows the share of the stop time included the stops caused by disruptions in the stick stacker section and used for estimation the use of degree.

The use of degree for the stick stacker section is 60%.

48

5.5 Planing mill

The diagrams 9, 10 and 11 show stops occurred in the first section of the planing mill.Seven stop codes to the left are caused by disruptions in the section that was studied.Six stop codes to the right are caused by disruptions occurred in the rest of the sections of the planing mill.

The diagram 9 represents the total picture of measuring for the both types of the packages: with sticks and without sticks. The diagram 10 shows results of processing the packages with sticks.The results of processing the packages without sticks are viewed in the diagram 11.

Pareto over planner mill total picture

4,1% 3,7% 3,1% 2,8% 2,2% 1,1% 0,6%

47,0%

9,7% 8,9% 7,5% 5,8%3,4%

0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

Elevat

or

Feeder

Stick ar

ea Tilt

Elevat

or co

nveyo

r

Operat

or ar

ea

Operat

or co

nveyo

r

Planner

Packag

e are

a

Cutter

Woo

d Eye

Sortin

g are

a

Other

Stop causes

Per

cen

t

Diagram 9. Shows the share of the total stop time in the studied section of the planning mill.

Handling of packages with sticks took the majority of the total measuring time therefore the common picture of results in the diagram 9 is similar to the results viewed on diagram 10.

49

Pareto planner mill with sticks

5,0% 3,8% 3,2% 3,1% 2,2% 1,2% 0,7%

49,2%

11,6%7,7% 6,6% 5,8%

0,0%

10,0%

20,0%

30,0%

40,0%

50,0%

60,0%

Elevat

or

Stick ar

ea Tilt

Feeder

Elevat

or co

nveyo

r

Operat

or ar

ea

Operat

or co

nveyo

r

Planner

Packag

e are

a

Cutter

Woo

d Eye

Sortin

g are

a

Stop causes

Per

cen

t

Diagram 10. Shows the share of the total stop occurred in the studied section when the packages have sticks and come to the planing mill directly after the drying process.

Pareto planner mill without sticks

7,7%

2,3% 1,5% 1,1% 0,3% 0,2% 0,0%

46,0%

17,9%14,3%

7,6%

1,0%0,0%

5,0%

10,0%

15,0%

20,0%

25,0%

30,0%

35,0%

40,0%

45,0%

50,0%

Feeder

Elevat

or co

nveyo

rTilt

Operat

or ar

ea

Elevat

or

Operat

or co

nveyo

r

Stick ar

ea

Planner

Cutter

Woo

d Eye

Sortin

g are

a

Packag

e are

a

Stop causes

Per

cen

t

Diagram 11. Shows the share of the total stop occurred in the studied section when the packages have no sticks and come to the planing mill after the grading mill.

50

The definition of pieces/minute through every conveyor is done in accordance to the real speed of each conveyor and the existent gaps between the boards. They are viewed in the table 1. These gaps were observed and measured by measuring common amount of boards passed every conveyor. Conveyors are shown on layout in appendix 5.

ConveyorLength

(m)Speed(m/min)

Gap(m) Pieces/min

Tilt conveyor 4,16 48 0,20 162Elevator 67After elevator 2,90 32 0,06 205Separator 601 band/operator 0,50 26 0,41 522 band/operator 0,70 26 0,21 863 band/operator 0,50 26 0,26 734 band/operator 0,57 26 0,38 55After operatorchain 1,25 25 0,32 60Last band 0,83 34 0,32 82Last chain 7,38 34 0,32 81Feeder 65

Table 1. Shows the mean value of pieces/minute done by every conveyor in the first section of the planing mill.

The table 2 represents the mean value of pieces/minute that is done by planer.

Boards through

the plannerMeasuring

time

Stop occured

in the first section

Stop occured

afterthe first section

Through the planner, all

stopsinfluence include

Through the planner,stopsof first section

influence

Through the planner

(200 m/min) if no stops

(pieces) (min) (min) (min) (pieces/ min) (pieces/ min) (pieces/ min)Total picture 81269 2831 239 1116 29 47 54Packages with sticks 47047 2042 212 896 23 41 54Packages without sticks 34222 789 27 174 43 56 54

Table 2. Shows mean values in pieces/ minute through the planer for two types of packages and with influences of different stops.

According to the table 2, the mean value is 23 pieces/minute through the planer when the packages with sticks are processed. If the influence of disruptions, occurred in sections after the planer, is not counted, it is done 41 pieces/minute. So, because of the disruptions occurred in the first studied section, it is lost 54 – 41 = 13 pieces/minute, 24%.

51

5.6 Calculating in excel for the first section of the planing mill

The use for calculating is to see what speed the different conveyors need to have in the first section to feed the planer well. These speeds are calculated according to the capacity of the planer, so the influence of the rest of the line is taken away. My study is done from the tilt to the board feeder just before the planer, see in appendix 5 layout for the first section.At the given data the planer speed is 200 m/min. The tilt has a theoretical capacity of 155pieces/minute. This capacity includes a cycle time for input and changing packages. This result for the tilt was used for the calculations shown on the pictures 22, 23.The gaps values are measured and viewed in the table 1, chapter 5.5.

1. Conveyors between the tilt and the elevator. The gap is estimated to 200 mm.2. Elevator. This gap is estimated to 420 mm.3. Conveyor between the elevator and the operator zone. This gap is 60 mm.4. Operator zone. Consists of feeders and belt conveyors. The gap is 410 mm5. Conveyors between the operator zone and the board feeder. This gap is estimated to

320 mm.

The filling degree over the elevator is taken 100% but it feels to be higher, because during the observation the elevator picked often more than one board per each holder.Waste of boards in the operator area is initial data and is about 4% in average.

There are some results from the calculating in the excel, for the investigated section in the planing mill.

Picture 22. Shows a calculation of conveyors speed for the first section in the planing mill in case of being gaps and 100% filling degree of the elevator and 4% waste of boards and the capacity for the planer 200 m/min.

It takes 8,3 minute to process one package through the planer.

52

Picture 23 represents necessary speeds of all conveyors in the first section to feed the planer in case of the maximum speed for the planer of 350 m/min.

Picture 23. Shows a calculation of conveyors speed for the first section in the planer mill in case of gaps existing and 100% filling degree in the elevator and 4% waste of boards and the maximum capacity for the planer is 350 m/min.

If it is possible to optimize speed over these conveyors the time for one package will take 4,7 minute.Compare to the results viewed on the picture 22 it gives an improvement ((8,3-4,7)/8,3)x100 = 43,3 % better.

53

6. Discussions and conclusions

6.1 Availability in the saw house

6.1.1 Compare the present situation and the new measured availability

The availability gotten during the measuring in January of 2008 is a little lower compare to 2007 because of time reducing before to register stops as a downtime. In the year of 2007 the availability is 68%, see the figure 2, and the new measure gives 65% in the figure 3.

So it is effective to reduce the bound of downtime to be reckoned in case to get more realistic value of the availability.

According to the stop distribution around the areas, nowadays picture is similar to the year of 2007. The sawline gives the biggest percentage of stops. It is 43% of the total stop time in the figure 2 and 57% in the figure 3. During the weeks 4-6 in the year of 2008, the stop percentage for the sawline is higher compare to the data of 2007. It can be explained because one of the stop causes is called “other stops” on the data of 2007, see figure 2. Other stops take about 15 percentage of the total stop time for the year of 2007, and this gives exactly the difference in the stop percentage for the sawline between the years of 2007 and 2008.

6.1.2 New measured availability

The sawline has the biggest percentage around the total stop share in the figures 3 and 5.The results in these figures seem to be pretty similar because the measuring time was greater for the second group of the sawing patterns compare to the first group. A definition for the pattern sorting was given in the chapter 3.1.1. To look more detailed about reasons for the stops in the sawline is possible in the diagrams 1 and 3. Long stops for the pattern changing have the highest percentage of total stop share in the diagrams. Long stops for planks cutter DS-72+1 have second place in the share of the stop because of the same stops like the set ups during the pattern changing – it takes too long time to replace blades.

To decrease these stop causes it is possible to improve the set up time by SMED method for example and care more about to reach high precision for blades setting. SMED method is described in the chapter 4.9.

For the first group of sawing pattern (less than 5 or 5 pieces out from one log), the most problematic section is the saw in feed area, see the figure 4. Long stops in the saw in feed area take 45% of the total stop time in the diagram 2. It is because the saw in feed and debarking area has less capacity than the sawline. The disparity of capacities is felt especially for the reworking of logs of small diameters. Long stops in the saw in feed and debarking area include both types of stops: chronic and sporadic.

54

The sawline keeps the second place for causing stops, see the figure 4. According to the diagram 2, the high value of stop inside the sawline is given by long stops for the saw pattern changing and long stops on conveyor after sideboards cutter DS-72. The reason that is difficult to centre and fix blocks on this conveyor is because of the small dimensions of blocks and the high speed of feeding.

6.2 Use of degree in the sawline

The use of degree for the sawline is viewed in the diagram 4. The share between stop codes inside of the sawline gives the most high percentage of stop time belong to stop for the pattern changing. Also stop codes named DS-72+1, SBF-2 and BBF-4 have a high percentage in the diagram 4. It seems that it takes too long and it happens too often to change blades or knives in these machines DS-72+1, SBF-2 and BBF-4. These stops are chronic and happen frequently during the process. It is the same share of total stop in the diagram 6 because the saw patterns of the second group were handled mostly during the measure period. The reason for the pattern sorting was given in the chapter 3.1.1.

One of the leading stop codes in the diagrams 4 and 6 is stop occurred on area of centring machine KSI-7 and the following conveyor. This stop was sporadic (broken chain on the conveyor after KSI-7) and it took too long time to repair this machine.

According to the diagram 5 for the first group of the saw patterns, the biggest amount of stops has the conveyor after DS-72, the conveyor following sideboards cutter. On this conveyor the largest stop is caused by positioning and location of blocks, which comefrom DS-72. The difficulty of moving of the blocks to the machine DS-72 can depend on the centring devices that hold blocks on this conveyor. These devices don’t handle well blocks of small size. If the sawing pattern is less than 5 boards from a log, usually thediameters and blocks dimensions are small; blocks have the tendency to drop of the conveyor. These stop have the chronic character and appear often.

The stops of the sawing pattern changing and stops for DS-72+1 machine are high as well in the diagram 5. It shows that the problem of blade changing does not depend on sawing pattern in any higher degree.

55

6.3 Stick stacker

According to the diagram 7, the conclusion is that 32% of the time the stick stacker area does not work because of the stops appeared in other areas: the saw in feed, the sawlineand the green sorting. So the stick stacker does not get any boards or planks to handle. The truck works well and it gives the smallest amount of stops.

According to “Best practice” the investment should be done in relation to stop reasons whichinfluence on supplying the stick stacker. That means that during the whole available running time, the stick stacker area should get enough material to work with. In this case, efforts should be directed to decrease the lack of boards. It is necessary first to make some improvements in the sections that are located before the stick stacker section in the saw house: the saw in feed, the sawline and the green sorting.

Stops, occurred inside of the stick stacker area, are divided to 4 causes, see the diagram 8. “Boards area” has the most problems such as the work of the elevator, problems with a label device, crossing of the boards over all the conveyors.

Stop time that takes to change the package (the time from finishing the package to startingto make the new one) is also high.

It is difficult to avoid this stop at all, but necessary to close it to the cycle time of a stick stacker machine.

The definition for the Best practice will be:

To make the use of degree as high as possible for this section. To decrease delays of the truck work and the lack of the boards as low as possible.

56

6.4 First section in the planing mill

The measuring, which was done at the first section in the planer mil, was for two types of the packages:

Packages with sticks, directly after the drying kilns Packages without sticks and after the grading mill.

So the boards from the packages without sticks have a higher quality, compare to first type of packages. But dimensions of boards were the same for both types of packages.

Results for packages with sticks are shown in the diagram 10. Most problems occur on the planer. It is 49% of the total stop time. The studied section of the planing mill has 19,2%of the total stop. The highest percentages of stop that are shown belong to the elevator, the sticks area and the tilt. These problems are connected with elevator construction, arrangements of sticks output and with quality of boards.

The possible conclusion is to use the existing chain conveyor instead of the elevator in the zone for the elevator. If it is possible it will keep the same gaps that exist on the conveyor between the tilt and elevator. And it will help to avoid such kind of the common problems like boards are stuck and crossed in the elevator pocket.The quality of boards is possible to increase by processing boards first through the grading mill. It gives the reducing of the total stop time about 30% in the observed section and help to avoid the stops caused by the sticks disruption.Also it is necessary to fix the problems occurred after the studied section. These zones with problems are viewed to the right in the diagram 10. The focus should be on the planer first.

In the diagram 11, the results for the packages without sticks from the grading mill areviewed. Still, the planer has the biggest downtime in the production time. And like in the diagram 12, the percentage of the total stop time for the planer is 46%. Problems that lead to stop the process inside the planer can be mainly related to the technical devices of the planer. According to the diagram 11, it is visible, that stops appear mostly on feeder and conveyor between the elevator and the separator at the operator area. This conveyor is named “elevator conveyor” in the diagrams. The problem is that there are too many boards come from the elevator to the conveyor following the elevator. The boards form a second layer on this conveyor, and it takes time for operator to spread them out. Stops on elevator do not have the major part in the total stop time.

According to the table 1, the bottle neck is operator area, because through this area go just 52 pieces/minute, the least amount of boards in this section.

57

6.5 Use for the calculating in excel for the planing mill

The comparison of the results in the table 1 and in the picture 22 shows that real speeds of the conveyors viewed in the table 1 at the operator area should be a little bit higher like it is shown in the picture 22 to keep essential capacity of pieces/ minute. So from 26 m/min to about 29 m/min over operator area.

According to the results shown in the pictures 22 and 23 it is to get smaller gaps between the boards and then it is not necessary to run the conveyors with so high speeds. So first, it is to optimize the gaps and find the harmonic speeds for these conveyors.

The increasing of the planer speed from 200m/min to maximum 350 m/min gives about 43% of improvement of processing time for one package through the studied section.

6.6 Achievements of the project

The new measured availability of the saw house is 65% for 127,5 hours of the measuringduring the weeks 4-6 of 2008.

The short stops (from 10 second to 1 minute) are 6% of the total stop time during the measuring. The value of the short stops in percentage was not so high but it gives about 2,3 hour per 1 productive week.

The section that gives the biggest amount of the short stops is the saw in feed and it is related to the capacity problem like lack of logs in the sawline.

According to two groups of sawing pattern the pictures look like this:

The sawing patterns are 5 or less than 5 pieces from a log:- Availability of the saw house is 71%.- Saw in feed has the greatest percentage of total stop - 48 %.

The sawing patterns are more than 5 pieces from one log:- Availability of the saw house is 63%.- Sawline has the greatest percentage of total stop - 60 %.

The use of degree of the sawline is 76%. The largest stop in the sawline belongs to the long stops for the pattern changing and it is 22,5% of the total stop.

The availability for the whole year of 2007 is 68 %.

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For the planing mill:

The mean value through the planer is 23 pieces/min during the whole measuring time. 24% of the theoretical capacity (54 pieces/min) is lost because of the disruptions occurred on the first studied section of the planing mill.

The mean value through the operator area is 52 pieces/min. This value was calculatedaccording to speeds of the conveyors and gaps. It is less than the maximum capacity calculated in accordance to the established speed of the planer. Losses are related to the speeds of conveyors and the speed of the separator at the operator area.

It is important to notice that the time of the measuring was too small for both sawmill and planing mill, so results can be different if the time of the measuring increase. For all conclusions at the planing mill it should be done more measuring to get more common picture so right decisions can be done.

59

7. Suggestions for the continues work

7.1 Sawmill

1. Use SMED method to change the sawing patterns.

2. Make a detailed study in the saw in feed and make the improvement there according to achieved results from the study. This measuring is exactly done like the measuring for the use of degree in the sawline. But put the measuring point of the flow in the saw in feed section.

3. Continue the work at the stick stacker section. Make it more detailed and make the improvement to achieve a higher use of degree.

7.2 Planing mill

1. Make a detailed study on the planer, so it can run with the maximum capacity.

2. Do a study on the areas: packaging, the cutter, “Wood Eye” and improve them.

Improve the measured section so the planer and the rest of the planing mill can run with the maximum capacity or faster than 52 pieces/minute which is the maximum for the first studied section.Some areas to improve in the studied section are:

3. Elevator.4. Feeder. 5. Stick area.6. Tilt.7. Elevator conveyor.

These parts of the section before the planer it is necessary to upgrade to get a higher capacity.But if the improvement for the planer will be succeeded the points 3 – 7 are not necessary to look at.

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Reference

Bicheno, J. (2004). The New Lean Toolbox , TOWARDS FAST, FLEXIBLE FLOW. Buckingham: Moreton Press.ISBN 978-0-9541244-1-0

Dennis, P. (2007 a). Lean Production Simplified. A Plain-Language Guide to the World’s Most Powerful Production System. Second edition. Malloy Lithographing. Page 160.ISBN 978-1-56327-356-8

Ilsley, R. (2004). Best Practice, What is it, How to implement it, A practical primer for every manager to implement Best Practice models. Management books 2000 LTD.ISBN 1-85252-466-9

Imai, M. (1997a). Gemba Kaizen, A commonsense, low-cost approach to management. McGraw-Hill. page xxiii – xxx.ISBN 0-07-031446-2

Ljungberg, Ö, (2000 a). TPM vägen till ständiga förbättringar. Lund: Studentlitteratur AB. Page 48.ISBN 91-44-00837-6

Nord, C, Pettersson, B och Johansson, B. (1997). TPM Total Productive Maintenance med erfarenhet från Volvo. 3:e uppl. IVF Industriforskning och utveckling AB. ISBN 91-972795-8-7

OEE for Operators, Overall Equipment Effectiviness. Created by: The productivity press development team. New York: Productivity Press.ISBN 978-1-56327-221-9

Santos, J, Wysk, R A, Torres, J M. (2006 a) Improving Production With Lean Thinking. Hoboken, New Jersey: Wiley & Sons, inc. Page 120 – 146.ISBN 0-471-75486-2

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Sayer, N J, Williams, B. (2007 a). Lean FOR DUMMIES, A Reference for the Rest of Us!Hoboken: Wiley Publishing, Inc. Page 72.ISBN 978-0-470-09931-5

Sayer, N J, Williams, B. (2007 b). Lean FOR DUMMIES, A Reference for the Rest of Us! Hoboken: Wiley Publishing, Inc. Page 108.ISBN 978-0-470-09931-5

Sayer, N J, Williams, B. (2007 c). Lean FOR DUMMIES, A Reference for the Rest of Us! Hoboken: Wiley Publishing, Inc. Page 182 – 183. ISBN 978-0-470-09931-5

Sayer, N J, Williams, B. (2007 d). Lean FOR DUMMIES, A Reference for the Rest of Us! Hoboken: Wiley Publishing, Inc. Page 204ISBN 978-0-470-09931-5

Sayer, N J, Williams, B. (2007 e). Lean FOR DUMMIES, A Reference for the Rest of Us! Hoboken: Wiley Publishing, Inc. Page 336 – 344. ISBN 978-0-470-09931-5

TPM for Supervisor. (1992 a). Created by: The productivity press development team. Based on a work by Kunio Shirose and Seiichi Nakajama of the Japan Institute for Plant Maintenanca (JIPM).New York: Productivity Press.ISBN 1-56327-161-3

SCA Timber, Rundvik sawmill URL:http://www.timber.sca.com/ (2008-03-13)

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Appendix

63

Appendix 1: Layout Rundvik sawmill

Sawline area is divided into the colours in relation to stop codes

Green sortingArea:

Boards

Green sortingArea: Planks

Stick stackerarea

Saw in feedand

Debarkingarea

Measuring point for the availability

andthe use of degree for

the sawline

64

Appendix 2: Data for the present situation at the sawmill:

Availabilty

Planned production

time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 67%

25440 8295 3914 4381 1380 4196 718 266 493 1242

YearWeek 701 - 704

Availabilty

Planned production

time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 69%

28260 8829 3680 5149 2731 3276 815 524 195 1288

YearWeek 705 - 708

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 66%

26880 9026 3279 5747 2189 4050 544 742 121 1380

YearWeek 709 - 712

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 70%

22950 6978 2882 4096 1572 2893 562 845 71 1035

YearWeek 713 - 716

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 71%

21840 6429 2909 3520 1284 2611 869 228 68 1369

YearWeek 717 - 720

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 68%

24060 7619 3022 4597 1210 3858 754 1067 89 641

YearWeek 721 - 724

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 72%

13440 3796 2002 1794 483 1598 725 398 16 576

YearWeek 725 - 728

65

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 64%

26880 9773 3889 5884 1526 4118 1472 1269 124 1264

YearWeek 729 - 732

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 66%

6720 2253 913 1340 650 861 193 514 21 14

YearWeek 733 - 736

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 70%

13980 4126 1867 2259 434 1893 710 467 107 515

YearWeek 737 - 740

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 67%

20700 6858 2532 4326 1002 2077 983 246 219 2331

YearWeek 741 - 744

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 69%

26880 8291 3632 4659 1810 3428 859 994 212 988

YearWeek 745 - 748

Availabilty

Planned prod. Time

Total stopinclude all sections

Total stopinclude all sections

short stop

Total stopinclude all sectionslong stop

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt 68%

258030 82273 34521 47752 16271 34859 9204 7560 1736 12643

YearWeek 701 - 748

Saw in feedTimmerintag

SawlineSåglinje

Green sorting

Råsortering

Stick stackerStrölägg

Rest products(Chips and Sawdust)Biproduktshantering

OtherÖvrigt

20% 42% 11% 9% 2% 15%

66

Appendix 3: Data for the stick stacker:

TT:MM Secnds23:03 82980

Total measuring time

Time to use of degree stick stacker 69703Total stop time at stick stacker area 27771Flow time 41932Use of degree stick stacker section 60,2%

Data for calculating use of degree at stickstacker section

Lack of boards 32,0% 13129Boards area 29,8% 12231New package 19,6% 8058Sticks area 9,7% 3969Dimension marking 8,6% 3513Truck 0,4% 148

100,0% 41048

The whole picture stick stacker section

Boards area 44,0% 12231New package 29,0% 8058Sticks area 14,3% 3969Dimension marking 12,6% 3513

100,0% 27771

Picture of use of degree stick stacker section

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Appendix 4: Data for the planing mill:

TT:MM MinuteTotal picture 47:11:00 2831With sticks 34:02:00 2042Without sticks 13:09 789

Start Boards in planner Waste of boards Finish Boards in planner Waste of boardsTotal picture 118160 3932 199429 6661With sticks 73618 3709 120665 6231Without sticks 44542 223 78764 430

From tilt Into the planner Waste of boards Waste (%)83998 81269 2729 3,2%49569 47047 2522 5,1%34429 34222 207 0,6%

Elevator 4,1% 3363Feeder 3,7% 2997Stick area 3,1% 2504Tilt 2,8% 2279Elevator conveyor 2,2% 1764

Operator area 1,1% 921Operator conveyor 0,6% 488

Planner 47,0% 38234Package area 9,7% 7857Cutter 8,9% 7252Wood Eye 7,5% 6134Sorting area 5,8% 4751Other 3,4% 2736

100,0% 81280

Total picture

Elevator 5,0% 3322Stick area 3,8% 2504Tilt 3,2% 2100Feeder 3,1% 2065Elevator conveyor 2,2% 1481

Operator area 1,2% 791Operator conveyor 0,7% 461

Planner 49,2% 32683Package area 11,6% 7741Cutter 7,7% 5097Wood Eye 6,6% 4411Sorting area 5,8% 3832

100,0% 66488

With sticks

68

Feeder 7,7% 932Elevator conveyor 2,3% 283Tilt 1,5% 179Operator area 1,1% 130Elevator 0,3% 41

Operator conveyor 0,2% 27Stick area 0,0% 0

Planner 46,0% 5551Cutter 17,9% 2155Wood Eye 14,3% 1723Sorting area 7,6% 919Package area 1,0% 116

100,0% 12056

Without sticks

Section before planner: 15% 11812Rest of the buliding: 82% 66732Other: 3% 2736

Total stop: 100% 81280

Dividing were the stop occours in the planner mill

Packages with sticks

After elevator

Band 1operator

Band 2operator

Band 3operator

Band 4operator

After operator

chainLast band

Last chain Feeder Tilt

17 2 2 1 1 4 2 18 1023 1 2 2 1 3 2 13 1218 1 2 0 1 3 1 1818 1 2 1 1 4 1 18 1118 1 2 1 1 2 2 21 1121 1 2 2 2 3 2 16 1113 1 4 2 1 3 2 24 918 0 2 2 1 3 2 22 1025 1 2 1 0 5 0 1718 1 2 2 1 3 2 22 916 1 2 2 1 2 4 12 921 1 2 2 1 3 2 20 1220 1 2 2 1 3 2 16 1118 0 2 1 1 4 2 15 1017 0 3 1 2 3 2 1823 1 2 1 2 3 3 12 1017 0 3 1 2 3 2 16 914 1 2 1 0 3 3 18 9

3 4 2 1 3 2 15 101 2 2 2 3 3 201 2 1 2 3 2 190 3 1 1 3 31 2 2 2 2

Avarage value/pieces 18,6 1 2,3 1,4 1,2 3 2 17,6 10,2 14All boards 1,767 0,095 0,2185 0,133 0,114 0,285 0,19 1,672 0,969 1,33All gaps 1,133 0,405 0,4815 0,367 0,456 0,965 0,64 5,708 2,83

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Appendix 5: Layout Rundvik planing mill first section:

TILT

= Belt

= Board feeder

= Chain

= Roller

Rest of the

planer mill

Operatorarea Elevator