pipeline integrity and difficult to pig pipelines

8/12/2019 Pipeline Integrity and Difficult to Pig Pipelines

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David Wint

Manager, Global Services DevelopmentTDW Services, Inc.

[email protected]

Difficult to PigPipelines
mailto:[email protected]:[email protected]


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Regulations

In 1994, 192.150 / 195.120 regulations were passed thatrequired each new transmission line and each replacementof line pipe, valve, fitting, or other line component in atransmission line must be designed and constructed toaccommodate the passage of instrumented internal

inspection devices. Design & Construction Standards to reduce internal corrosion on Gas

Transmission Pipelines Final Rule May 23, 2007 New and replaced gas transmission pipelines must be configured

to reduce the risk that liquids will collect in the line Have effective liquid removal features Allow use of corrosion monitoring devices in locations with

significant potential for internal corrosion


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What is Pigging ? Why Pig ?

Pipeline Design Pipeline Operations

Types of Pigs

When to Pig ? Pigging Safety

Pipeline Cleaning Geometry Inspection Metal Loss Inspection Crack Inspection Inhibition

All About Pigging


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Why Pig a Pipeline?

During the 1940s, pipelines in the United Stateswere mainly pigged to remove paraffin to increaseefficiency in crude oil pipelines in order tomaximize flow conditions for the war effort. Thepigging equipment utilized at that time was limitedto a few applications while being very crude innature. In today's world, pipelines are pigged for avariety of reasons and the pigging equipment usedis designed by engineers to perform particularfunctions.


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Piggability

RECOMMENDED PRACTICES

NACE 35100 In-Line Inspection Non-DestructiveTesting of Pipelines

NACE RP0102-2002 In-Line Inspection of Pipelines


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Piggability

Physical Characteristics (Pipeline Design) Line Pipe Grade Type of Welds Length

Fittings Internal Diameter Elevation Profile Tees

Bends Valves Spans


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Piggability

Line Pipe Grade

Class Location Definition192.5

The class location unit is an onshore area that extends 220 yards oneither side of the centerline of any continuous 1-mile length ofpipeline.

The class location is determined by the buildings in the classlocation unit . For the purposes of this section, each separatedwelling unit in a multiple dwelling building is counted as aseparate building intended for human occupancy.


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A Class 1 = 10 or less buildings intended for

human occupancy or an offshore area.

A Class 2 = Greater that 10 but less than 46buildings intended for human occupancy.

A Class 3 = 46 or more buildings intendedfor human occupancy; or

Piggability


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Class 3 - where the pipeline lies within 100yards of either a building or a small,

Well-defined Outside Area

Playground Recreation Area Outdoor Theater

Occupied by 20 or more persons on at

least 5 days a week for 10 weeks in any 12-month period

Piggability


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Class 4 - where buildings with four or morestories above ground are prevalent.

Piggability


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192.105 - Design of Steel Pipe

P = Design PressureS = Yield StrengthD = Outside Diameter

t = Wall ThicknessF = Design factor - 192.111E = Longitudinal joint factor - 192.113T = Temperature de-rating factor - 192.115

P = (2St/D)(F)(E)(T)


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P=2St (F)D

192.111

Class location Design factor (F)

1 .72

2 .60

3 .504 .40


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Type of Welds (Connections)

Acetylene welding was first used around 1911 to join pipe segments together (girth welding) and just prior to 1920, arc welding was introduced.

Chills Rings are sometimes called backup rings orspacers. These rings are machined pieces of metalthat conform to the dimensions of the joint design

used. Bell-to-bell joints that were welded togetherwith the use of a chill ring.


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Type of Welds (Connections) Chill Rings


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Type of Welds (Connections) Dresser Coupling


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Types of Welds (Connection)Dresser Coupling Pumpkin Repair Sleeve


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Types of Welds (Connection) Zap-Lok Connections


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PiggabilityLength

The distance between two pig traps is a variable andmust be determined for each specific pipeline. Some considerations:

Wear on the Pigs

Pipeline Product The following pipeline lengths are not uncommon; Natural Gas pipelines 50-100 miles between traps Refined Products Pipelines 100-150 miles between

traps Crude Oil Pipelines 150-200 miles between traps


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Piggability Dual Diameter Pipelines

Pipelines that have been designed toaccept input along their length may need toincrease in diameter as the through-putincreases. Instead of having traps installedat each change in pipe size reducers areused. Concentric reducers should be usedfor changes in diameter within a pipeline sothat the center line of the pig can remain onthe same plane as it makes the transitionfrom one size to another.


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Piggability Dual Diameter Pipelines


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Piggability

Reducers Typical Applications

Concentric - used in line Eccentric - used in Traps


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PiggabilityLinings

Pipelines are lined to help protect the inside ofthe pipe from the effects of the product and tocreate less flow resistance. Natural gaspipelines are usually internally coated with anepoxy fusion bonded coating applied undercontrolled conditions at the factory or a specialfield site. Wire brush pigs should not be usedon pipelines that have been internally coated. A

combination of Urethane blades, discs andcups should be used for maintenance pigging.


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PiggabilityBends

Examples of commonFactory Bends w/ 5D, 3Dand 1.5D Radius

Miter Bends are veryuncommon in the gasindustry and are locatedas a result of In LineInspection

Greater than 5D FactoryBends and/or FieldBends can be producedw/ a little advancedplanning


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Piggability Forged Bends

Bends with a relatively short radius mustbe factory made and are usually forged

to a number of different standard radii.The radius of a bend is measured to its center line. Short radius (one D) bends

should not be used in pipelines if youintend to pig the pipeline.


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Piggability Bends


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Piggability Bends


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PiggabilityField Bends

Field bends are often referred to as cold bends and when they are being formed it isimportant not to exceed the allowable yieldstress of the pipe material. Field bends arenormally 5 D and larger. Field bends shouldbe of a uniform radius and not contain anyflat spots or any other localizeddeformation. For pigging requirements anylocal deformation should not exceed 2 or 3%of the pipeline diameter.

b l


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Piggability Miter Bends

Miter bends are made by cutting the end of the pipe at an angle to achievea change in direction of the pipe. In general, miter bends should beavoided if you intend to pig the pipeline. If for some reason there is a miterbend in the line, you should contact your pig supplier and give them thedimensions of the miter bend so they can determine if your pig will passthrough the miter bend.

i bili


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PiggabilityDiameter and Wall Thickness

One of the largest cost of a pipeline is the cost ofthe pipe. In the process of the design engineeringphase the through-put is used to determine thepipe diameter and the pipe wall thickness.

The wall thickness may vary due to externalconditions such as High Consequence Areas, Road Crossings, Railroad Crossings, etc.

As long as the wall thickness is such that theinside pipe diameter is within the tolerancesallowed by the pig manufacturer the varying wallthickness should not be a problem .

Pi bili


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PiggabilityTees

Tees with outlets greater than 50% of the maindiameter should be barred to reduce the risk ofsticking pigs. This is especially true in laterals withhigh flow conditions

Pi bili


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PiggabilityOff-Takes

Unbarred Tees Forged tees are usually used for installing off takes (outlets) in a

pipeline during construction. Most conventional pigs will safelytransverse tees with outlets up to 60% of the nominal line size.

However it is good practice to install guide bars in all outletsabove 50%.

Off takes should not be installed adjacent to one another. At leastthree diameters of straight pipe should be installed between any

two fittings.

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Piggability

Pigs can typically beconfigured to accommodateback to back laterals bylengthening the pig to avoidmodification of the laterals.

A perfect condition for

a stalled pig

Pi bili


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PiggabilityBarred Tees

Any off take that is more than 50% of the pipelinesize should have bars installed to assist the pigpast the opening without any damage.

The bars should be installed parallel to the axis ofthe pipe and spaced from about 2 apart for smalloff takes to about 4 apart for larger sizes.

Pi bili


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PiggabilityLaterals/Tees

Generic Suggestions for Barred Tees:

4 to 8 laterals 1 single bar centered intapped hole.

4 thru 10 Laterals w/ bars thick 10 and larger laterals 2 bars equally

separated in tapped hole.

12 and larger laterals bars thick

Minimum Requirements

Conservative Specifications 4 thru 10 - bars w/ 2 spacing

12 and larger bars w/ 2 spacing


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Pi bilit


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Piggability Seat Ring Spacing


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Pigg bilit


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Piggability Check Valves

By the nature of their design, check valves requirean area in the valve body that is larger that the pipeinside diameter. This requires the cups and/or discson the pig to be spaced far enough apart to span the

oversized area in the valve body. In addition the pigmust provide the force required to open the checkvalve fully for it to pass through.

Spheres are not suitable for pigging lines with check

valves. The sphere will drop into the oversize bodyand bypass. You must use the bump and run methodif you are going to pig with spheres.

Piggabilit


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PiggabilityCheck Valves

Make Piggable


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Make PiggableCheck Valves

Piggability


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PiggabilityElevation

Piggability


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Piggability Elevation

Pipe

Receiver

a

c

b

Depth of Cover (DOC)

Piggability


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PiggabilitySpans

Piggability


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PiggabilitySpans


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Piggability


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PiggabilityDrips

Piggability


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PiggabilityDrips

Piggability


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Piggability Other

Intrusive Repairs Pipeline Carrot


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Piggability


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PiggabilityOther

Coupon Holders

Piggability


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PiggabilityOperations

In the hydrocarbons field, refined products must bemonitored as their composition or the additives maychange, even though the same generic name is used

for their description. For example gasoline has been aproduct in pipelines for many years and has beenpigged with many types of pigs. However, morerecently, special chemicals have been added togasoline for environmental purposes and someelastomers that have been used in the past may nowbe unsuitable.

Special considerations must be made for productssuch as ammonia.

Product

Piggability


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Most utility pigs are molded or fabricated frommaterials normally considered as solids andtherefore are affected very little, if any by

pressure. Most foam pigs are open cell and also are not

affected by pressure while inflatable spheresshould be full of liquid and are also unaffected.

Pressure

Piggability


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Typical Differential Pressure (DP) Required to Drive a pig: DP (bars) = K (type of pig)

Nominal Diameter (inches)

K (Types of Pigs) Sphere and Foam Pig = 1 2 Cup Pig = 4 4 Cup Pig = 7 Disc Pig = 9 Cup Brush Pig = 12 Disc Brush Pig = 15 UT ILI Tool = 19 MFL ILI Tool = 24

Pressure

Piggability


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Typical Differential Pressure (DP) Required to Drive a pig: DP (bars) = K (type of pig)

Nominal Diameter (inches)

Example: 10-inch Disc Brush Pig (K factor = 15)

DP (bars) = 1510-inch

1.5 bars x 14.5 psi = 21.75 DP (psi)

Pressure

Piggability


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Flow Rate Most cleaning, batching and swabbing applications are run

on-stream and will have to be carried out at the velocity ofthe product stream.

Pigs are most effective if run at a near constant speed. Whenthe flow rate is low the pig may run in a series of start andstop motions, and it will not be very effective under theseconditions.

Pigs will not be effective if run at too high a velocity. This is

seldom a problem with on-stream pigging as the flow ratesare usually quite moderate. However, during construction,flow rates cannot always be controlled and it is then difficultto achieve maximum effectiveness.

Piggability


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Flow Rate

The following are considered to be typical speeds forutility pigging and are given as reference only.

Application Speed (Mph)New Construction 1 - 5On-Stream Gas 2 8On-Stream Liquids 1 8ILI Tools 2 7

Piggability


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Flow Rate

Gas velocity (Mph) is calculated with thefollowing formula:

(31210) (mmcfd)(psi)(d2)

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Flow Rate

Piggability


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Piggability Operations

TemperatureMost pigs use polyurethane seals and theallowable temperature range for this material isgenerally between 32 F. and 180 F. (0 and 82C.) Since most pipelines operate at ambienttemperatures within this range, this does notnormally create any problems for utility pigs.

Piggability


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Contaminants

Acid Gases

- Hydrogen Sulfide- Carbon Dioxide

Oxygen Bacteria

- Sulfate Reducing Bacteria

- Acid Producing Bacteria

Piggability


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Contaminants

Hydrogen Sulfide- Acute poisoning (>20 ppm)- Explosive (4% - 44% in air)

Mercaptan- Unnecessary calls to emergency response personnel

Carbon Dioxide- Asphyxiation- Frostbite

Oxygen- Explosive in Methane

Piggability


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Contaminants

Bacteria- Sulfate Reducing Bacteria (SRB) - SRBs use the sulfate ion

in water as a food source. Through their metabolicprocess, the sulfate is converted to H2S.

- Acid Producing Bacteria (APB) - APBs producecarboxylic acids and/or CO2 as a by-product of theirmetabolic process

Piggability


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Contaminants

Solids Iron Sulfide (pyrophoric material will ignite spontaneously in air) Iron Carbonate Iron Oxide

Other PCBs (acute poisoning source is typically from compressors) NORMS (Natural Occurring Radioactive Materials) source is

radium-226 and radium-228 are the decay products of uraniumand thorium that are present in subsurface formations.

Piggability


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ggab tyLauncher Receiver Design

Make Piggable


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ggPurpose of Launcher & Receivers

The primary purpose of a Pig Launcherand Receiver is to Launch and/or Receive apipeline pig into a pipeline system without

interruption of the flow.

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gg yLauncher & Receivers

The rule of thumb for the length of thelauncher barrel is 1.5 times the length of thelongest pig to be used.

It is often the case that the pigs have not beenselected at the time the traps are designed so analternative rule of thumb for the length of the

barrel, assuming single module pigs will be used,is 2.5D.

Utility Pigs

Piggability


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Many In- Line Inspection, or ILI tools, aretypically constructed of several modules joinedtogether. When these and similar extra -long ILI

tools are to be used, the launcher barrel shouldbe at least 1D longer than the overall length ofthe longest pig. Except for the length, all otherdimensions will be the same as for utility pigs.

In-Line Inspection Tools

Piggability


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Spheres have a single line of seal and therefore,must be treated differently than pigs that will haveat least two and often four or more seals per pig.Since spheres are the same dimension in alldirections, they are not self-guiding and will try tofollow the flow within the pipeline even throughsmaller pipe sizes.

Spheres


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Performance Enhancing Features


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gReceiver With Drain Lines


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Design Codes


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g

Pig launching and receiving systemsshould be designed according to thefollowing design codes :

- ASME B31.4 Liquid Pipelines

- ASME B31.8 Gas Pipelines

- ASME B31.3 Process Piping

- ASME Section VIII

- Other

Launcher & Receiver Types


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ypPigging Systems



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Automated Sphere Launching Systems

Launcher & Receiver Types:


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Vertical Automated Systems



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Sloped Automated System



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Automated Batch System



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Temporary Launcher & Receivers

Temporary launchers are sometimes used for thefollowing purposes:

Clean Short Pipeline Segments such as HCAs Perform Hydrostatic Pressure Tests

Decommissioning of Pipeline from Service Economic Purposes Rent instead of Purchase Specialty Pigging Operations such as Blow Through Cleaning

and Inspection

Proving Pigging Operations New Construction Cleaning & Inspections Off-line Pigging Operations



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Specialty Pigging - Tethering

Pig Handling Equipment


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These trays are

equipped with a push-pull mechanism toeither push the pig intothe launcher barrel orpull the pig from thereceiver barrel.

They allow for ease of

handling of the pigs .


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Pigging


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gg g

Why Pig a Pipeline Pipeline Pigs

- Pigging during Pipeline Construction

- Pigging during Operation Cleaning Batching Displacement Inspection

Pigging During Construction


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During pipeline construction it is notuncommon that a certain amount of debriswill find its way into the pipeline. This debrismust be removed prior to commissioning the

pipeline and it is normally removed by pigsthat the contractor will run afterconstruction with compressed air.



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Once the debris is removed from the pipeline it isnot uncommon to run the following tools;

Gauging Pig

Kaliper Tool Deformation Tool

These tools are run to determine if there are anyabnormalities in the pipeline such as reductions andout of round conditions.

Pigging During ConstructionG i Pi


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Gauging Pig

Pigging During ConstructionK li Pi


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Kaliper Pig

Pigging During ConstructionD t t bl Pi F t


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Bends - Dents Valves - Ovalities Wall thickness changes - Other Tees - Misalignments Taps - Mitre Bends Girth Welds - Wrinkles/Buckles

ConventionalKaliper

Detectable Pipe Features

Pigging During ConstructionTypes of Geometry Pigs


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Mechanical:

Movement is detected inmechanical arms oriented at therear cup as tool traverses thepipeline

Electronic Clock Kaliper

Hi Resolution Deformation

Types of Geometry Pigs

Pigging During ConstructionKaliper Pig


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Kaliper Pig

Pigging During ConstructionD f ti T l


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Deformation Tool


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Pigging for Hydrostatic TestingDisplacement of Air


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Displacement of Air

During the hydrostatic testing process batching pigsare used to displace the air from the pipeline duringthe fill-water process. The batching pig is placed intothe pipeline first and then moved through the

pipeline by the fill-water process to displace any airin the pipeline.

Pigging for Hydrostatic Testingi


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Drying

Once the pipeline has been hydro-tested thecontractor will dewater the pipeline using a series ofpigs pushed through the pipeline with drycompressed air. After the water has been displacedthe pipeline normally needs to be dried. This isaccomplished by blowing dry air or nitrogen throughthe pipeline in conjunction with running numerousfoam pigs.

Pigging for Hydrostatic TestingCommissioning


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Commissioning

When the pipeline is dried to specification, the nextstep in the process is to commission the pipeline.The commissioning process is almost alwaysaccompanied by the utilization of pipeline pigs,

which are usually pushed through the pipeline withits product.

Operational Pigging


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Essentially there are four main reasons why apipeline needs to be pigged duringoperation;

Cleaning Batching Displacement Inspection

Operational PiggingCleaning


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Cleaning

Cleaning a pipeline during operation is consideredto be a maintenance procedure that needs to bedone on a regular predetermined frequency usingpigs adequately designed for the proper cleaningapplication. The pigging operation will almostalways increase the flow efficiency and reduceoperating costs.



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Cleaning

In pipelines that have low flow conditions it is moreprevalent to see an increase in the collection of freewater in the bottom of the pipeline, even in crude oillines. In low flow conditions you need a mechanicalmeans (pigs) to remove both the solids and liquidsthat collect in the bottom of the pipeline to helpprevent the process of internal corrosion.



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Cleaning

After a pipeline has been in service for a periodof time, 100% efficiency cannot reasonably beexpected. However, routine pigging can keep apipeline operating at 90 to 95 percent capacity.It is not uncommon to increase the flow rate of apipeline by 3% with a single cleaning pig run.The cleaner the pipeline is, the more effectivethe throughput. Higher effective throughputmeans lower transportation costs for the

pipeline company.

Operational PiggingOnline


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Online

- Design pressure 1440 PSIG, ASMEClass 600.

- Nominal Capacity 400 MMSCF/D

- Site glasses and liquid levelcontrollers.

- 140 BBL/M liquid dump rate.

- 3 Relief valve & 4 rupture disc

pressure protection.- Specifically designed for On-

stream pipeline cleaning of gaslines.

Gas/Liquid Separators

Mechanical or Fluid Enhanced

Operational PiggingOff li


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Off-line

Media to propel pigs- Water- Air

- Nitrogen- Wire-line Equipment Determine velocity to propel pig at appropriate speed Determine differential pressure Determine quantity of propellant

Mechanical or Fluid Enhanced

Operational Pigging Magnetic Cleaning Pig for Ferrous Materials


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The removal of this type ofdebris is a must beforeattempting to run CorrosionInspection Pigs.

Debris such as welding rods,bolts, tools, etc., is very difficultto remove with conventional pigsas the pigs typically push theseobjects for some distance and

then ride over them.

Magnetic Cleaning Pig for Ferrous Materials

Operational PiggingDummy Tools (w/gauging plate)


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Dummy Tools (w/gauging plate)

Operational Pigging Black Powder


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Typical results of using mechanical brushcleaning pigs for removal of black powder.

Black Powder

Operational Pigging Black Powder


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Effective results of using cleaning fluids andbrush pigs with RealSeal Cups.

Black Powder

Operational Pigging B fit f Cl i g


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Benefits of Cleaning

IncreasesThroughput/Efficiency

Prepares Pipeline for In-Line Inspection

- Prevents Tool Damage- Allows the Collectionof Critical Data

- Reduces Project Cost

Removes corrosive materialsfrom pipeline- Oxygen- Carbon Dioxide

- Salts, Acids, Water- Rust & Scale- Hydrogen Sulfide- Black Powder- Miscellaneous

Operational PiggingAdvantages of Cleaning w/Detergent


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Chemically enhanced line cleaning produces:

Project total time lengths are compressed(results in cost saving in most cases)

Solids in suspension move through the line easier

Dry Iron Oxides are flammable in contact with O 2

Advantages of Cleaning w/Detergent

Operational PiggingBatching


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Batching is the process of moving different productsthrough the same pipeline. It is much more economicalto move several products in one pipeline than to laydedicated pipelines for each product. Batching pigs areused to separate the products and are normally madeup of either two or four cups. Cups are flexible andprovide a better seal than discs for product separation.

Batching

Operational PiggingBatching with Inhibitors


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The pipeline must be clean for the inhibitor to be

effective. The inhibitor must contact the pipe to be effective. The inhibitor application must be effective.

The quantity of inhibitor must be calculated for 100%coverage.

Batching with Inhibitors

Operational PiggingBatching with Inhibitors


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Batching with Inhibitors

Introducing a column of liquid between pigsfor the purposes of applying Inhibitor,biocides or internal coatings can be aneffective method to apply these materials.

Slug between pigs


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Operational PiggingInhibitor Application with V-Jet Pig


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Inhibitor Application with V Jet Pig



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V-Jet

PigSpray Nozzles

Inhibitor Application Pig

The spray head appliescorrosion inhibitor fluid to thetop quadrant of the pipeline.

The V-Jet is designed to act asits own reservoir in the eventthat it should pass a section ofpipe that would be void ofcorrosion inhibitor.

The V-Jet pig can be used asthe front and/or rear pig in abatching process.

Excellent de-watering pig.




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Inhibitor batching may also be made by introducing a slug of inhibitor solution. With the spray pig at the front of the slug (with a batching or foam pig at the back). Or with the spray pig at the back (w/ a batching or foam pig at the front of the slug). It was has been found that the spray pig is more effective at the back allowing gas flow

through to energize the spray.

Alternatively, the spray pig has been run as a de-watering pig. Serves to effectively re-distribute inhibitor-containing liquids to the top of the pipe. Creates an increasingly dense vapor cloud in front of the spray pig. The spray pig has been highly effective at controlling top of the line corrosion in multi-

phase gas gathering lines. In one case, corrosion rates dropped by an order ofmagnitude from 5 mills per year (mpy) to less than 0.2 mpy.


Operational Pigging Inspection


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Magnetic flux leakage (MFL) tools for corrosionmetal loss.

Ultrasonic tools for corrosion detection & crackinspection.

Kaliper tools for geometry inspection. Deformation tools for geometry and bend

inspection with telemetry data. Crack detection tools for determining

circumferential cracking. Survey or mapping tools with telemetry data.

Inspection

Line Cleanliness is Critical


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MFL Tools are the best & most expensive cleaning pigsavailable. Sensor Lift Off will reduce the intensity ofthe magnetic signal and will affect data quality.

You dont want MFL Tools to be a Cleaning Pig!

PiggingWhat Should My Cleaning Strategy Be?


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What Should My Cleaning Strategy Be?

How many runs does it take to clean a pipeline ?

What kind of pigs should I use ?

How often should I pig ?

Can a single Pig Train run reap the same benefits of multiple pigruns ?

Know your pipeline. Measure the results of your efforts.

If your program isn't working, try something different.

Stay open to new ideas and technology.

Basic Questions

In Order to Establish an Effective Pigging Program


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Select A Pig For Cleaning Applications


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The best choice is a pig with discs, conical cups, springmounted brushes and bypass ports. Discs are effective at pushing out solids while also providing

good support for the pig. Conical cups provide excellent sealing characteristics, good

support and long wear. Spring mounted brushes provide continuous forceful

scraping for removal of rust, scale and other build-ups on thepipe wall.

Bypass ports allow some of the flow to bypass through the

pig and helps minimize solids build-up in front of the pig. Alsoused for slowing the speed of the pig down.

RealSeal Cups


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RealSeal features multiple sealing lips,which means more effective sealthroughout the pipeline run.

With the RealSeal cups, sealing as the pigpasses girth welds in a pipeline become anon-issue.

Available in Vantage cups, heavy duty cupsand Ultra multi-lip discs.

Critical sealing applications such as nitrogenpurges, line filling for hydrostatic testingand cleaning.

Very effective in commissioning of lines,displacement and batch separation.

Also effective in cleaning operations actslike multiple scraper discs

Independent Sealing Lips

Conventional Cup vs. RealSeal CupDesign


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VS.

TDWs Multi -Lip RealSeal cups and discsare designed for applications in whicheffective sealing and extended life of pig

cups are critical.

Sealing lips are always ahead or behind thegirth weld when the cup is passing continuously maintaining a seal.

Conventional cups allow by-pass

due to irregularities on theinternal contour of girth welds

Approaches to Pipeline Cleaning


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Special features that can be added to pigs:

Magnets

Blades forWax Removal

Wear-CompensatingBrushes Studded Pig

Special Purpose Pigs & Components


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Wear-compensating / pit-cleaning brushes

Wear-compensating brush pads andwax-scraping blades Scraper discs

Discs tend to do a much better job of scrapingthan cups which tend to ride up over debris.

Discs can be quite effective at removing loose

powders, light debris and soft wax.

Pit-Cleaning Brushes

Scraper Discs

Scraper Blades& Brush Pads


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Cast Urethane Pigs


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Undersized Guide Disc

5D1C

4D2C-Guage Plate

Disposable Pigs

Multiple discs with single cup on rear.

Multiple discs with cup on front and rear. RealSeal configuration option for rear

cup. Brush wrap, gauging plate and bypass

option. Will also hold transmitter and ortrip magnet.

Undersized front disc or cup to aid inlaunching of pig.

Available in 4 to 12

4D2C

4D2C-Brushes5D-Offshore

Sphere Pigs


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99% of the time, spheres are used topush liquids out of natural gasgathering lines.

Gravity allows the automated launchingand receiving of spheres which makes

them very easy to use and very costeffective.

Typically, lines have been designed tohandle spheres.

Seamless, one-piece, inflatable. Spheres are filled with liquid and can

also be inflated to compensate forwear.

Foam Pigs


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Light/Medium Cleaning

Drying

Bristles

Aggressive Cleaning

RS-7-Abrasion resistant polyurethane

foam with honeycomb texture-wipingand scraping effect.

RBR-7 (Bristle)-Effective cleaning andremoval of solids.

RRR-7 (Rough Rider) Used for internallycoated lines and crude oil linescontaining paraffin.

Whiteskin-Shorter runs primarily fordrying after dewatering of lines thathave been hydrostatically tested.

(Redskin pigs also have the ability forbypass to be added

Brush Pig Configurations


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What Type of Brush Should I Use?

Circular Brushes


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Bi-Directional

Come in all sizes

Can be stacked in dense cleaning packs

Provide good centering guide in the pipeline

Not effective in cleaning deep pits

Not effective in pipelines with multiple IDs

Can be Damaged in tight bends and pipe ID anomalies

Advantages

Disadvantages

Pad Type Brushes


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Pads are wear compensated & can conform to bends.

Effective in multi-diameter pipelines.

Buggy spring mounted pads are Bi -Directional.

Can articulate thru pipeline anomalies.

Size restrictions.

Not effective in cleaning deep pits.

Lever mounted pads are not Bi-Directional.

Advantages

Disadvantages

PitBoss Pig Guide/Cleaning Disc


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Scraping Action

RealSeal Cups

Aggressive Cleaning Pig

Available in sizes from 6 and larger.

Is designed to remove deposits frominternal pits while insuring excellentgeneral purpose cleaning pig.

Pit cleaning wire brushes are designedto improve effectiveness of corrosioninhibitors.

Each wire scrapper acts independentlyas both a spring (forcing itself out andinto the pit) and as a scraper.

PitBoss is also available in dualdiameter configuration.

Magnetic Cleaning Pig forFerrous Materials


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Ferrous Materials Debris such as welding rods, bolts, tools, etc., is very

difficult to remove with conventional pigs as the pigstypically push these objects for some distance andthen ride over them.

The removal of this type of debris is a must beforeattempting to run Corrosion Inspection Pigs.

Progressive Pigging


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The more unknowns that exist in a pipeline segment, the

less intrusive the initial pig run should be start gentlyand use the following sequence. Use the followingexample:

Foam Pig

Foam Pig with Bristles Steel bodied Mandrel Pig With Brushes Steel bodied Mandrel Pig with Aggressive Brushes Gauging Pig

Dummy Pig w/ Magnets Geometry Pig Metal Loss Pig

Sampling & Monitoring


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Pigging Samples Solids Sampling Liquids Sampling


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Tracking


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Pig Tracking Equipment

Surveys- Centerline

- Depth of Cover

- AGM- Anomaly

Defect Assessment

Tracking


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Reasons for Pig Tracking- Locate a Stuck Pig- Track a Nitrogen Purge

- Monitor Progress of Cleaning or Batching Pigs- Track an Inspection Tool

- Identify Pig Passage

Pig Tracking EquipmentPig Sigs


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Pig Tracking Equipment Non-Intrusive Pig Sig


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Bands directly to the outside of a pipeline. No part of the unit enters the pipe (no need

for seals or o-rings to contain pipelinepressure).

No welding/tapping is required . Unit can be placed at nearly any location on

a line and can be moved easily (no need forTOR).

Bi-directional detection.


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Pig Tracking EquipmentReceiver


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Pig Tracking Equipment Geophone


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Pig Tracking EquipmentTracking Techniques


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Leapfrogging - Tech A goes to first track point.Tech B is located at second track point. As pigpasses Tech A he records time and notifiesTech B. Tech A then proceeds to third trackpoint. Repeated until pig is received.


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Centerline Survey


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Flagging Point of Inflection


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Depth of Cover Survey


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The DOC is calculated by the followingformula:

bD

depthlocator PipelineDOC2

Where,DOC = Depth of coverPipeline locator depth = pipeline depth as measuredby the pipe locatorD = diameter of the pipelineb = separation between the ground and the lowerend of the instrument

Above Ground Markers


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A tool designed to be placed above the pipeline usually at adocumented GPS location which records tool passage andcommunicates with satellites. Recognizes the magnetic field asthe tool passes.

Placement should be at points where GPS coordinates have been

established & documented. Will store multiple passes. Tool and AGM are synchronized. Accuracies depend on the make of AGM.

Threats - Flammables


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Blow-Down Opening the Closure Static Electricity Equipment & Cathodic Protection Rectifiers Sources

- Natural Gas

- Condensate

- Methanol- Pyrophoric Substances

Threats - Chemicals


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Blow-Down Opening the Closure Sources

- Methanol

- Corrosion Inhibitors

Threats - Toxicity


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Blow-Down Opening the Closure Sources

- Odorants

- Methanol

- NORMS

- PCBs

Summary


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Many pipelines can be made piggable with readilyavailable components.

System information is critical when preparing for In-Line Inspection or any other assessment method.

Pipeline Cleanliness is a critical part of In-LineInspection.

Tools Have Strengths & Limitations. We need toapply the right tool for the right job.

pipeline integrity and difficult to pig pipelines

Documents