guidelines for btl

8/13/2019 Guidelines for BTL

1/10

Action Plan for Prevention of Flame Failure

Sr # Issue # Actions

1.cHealthiness of scanner cooling air hoses &

guide pipes

1 Proper soot blowing pressure to be ensured

after every overhaul by pressure setting

3 Healthiness of LRSBs to be ensured

3 Gun Cleaning to be done as per schedule

4 Oil filter cleaning to be done regularly

70%>200 Mesh/Retention 1%


2/10

Measures in place Remarks

Roll/Ring gap adjustment IN PM

Spring Pressures checking/adjustment

Roll wear monitoring Replace if more

Classifier adjustment

Cleaning of Filters IN PMFan O/H outage

Inspection during overhaul/ replacement if

necessary

Mill PM

Feeder PM

Ongoing; sootblower nozzle alignment checks

during overhaul IN PM

Ongoing IN PM

Being done as per operations requirement

Ongoing IN PM


3/10

Action Plan for Prevention of Clinkering & Ash Build up

Sr # Issue # Actions

E

Burner Tilt

3

In case of shear pin breakage it shall be attende

3 Regular preventive maintenance to be done to

maintain mill fineness within limits

2 Proper soot blowing pressure to be ensured

after every overhaul by pressure setting

4 Healthiness of LRSBs to be ensured

HCoal Burner

Healthiness 1Eroded coal nozzles/tips to be replaced during

opportunity shutdowns

1

After overhauling boiler/maintenance of

furnace, the boiler should be inspected and

loose material if any should be removed from

furnace/bottom ash hopper

2

Chemical injection (Polarchem) to help reduce

formation of clinkers by preventing fusion of

ash particles

J

Ash build up

preventative

measures

5

Availability of all ash discharge lines with

adequate HP pressure (for hydro ejectorsystem) and scrapper conveyors (Continuous

De-ashing system),Clinker grinders, hopper

gates, flushing nozzles shall be ensured through

regular PM

I

Other

operational

measures

70%>200 Mesh/Retention 1%


4/10

Measures in place Remarks

Being attended at the earliest

In case of jamming of tilt assembly due to clinkering or

deformation of burner compartments, the same shall be

attended at the earliest outage opportunity

Roll/Ring gap adjustment IN PM

Spring Pressures checking/adjustmentRoll wear monitoring Replace if more

Classifier adjustment

On going

Ongoing; sootblower nozzle alignment

checks during overhaul IN PM

Ongoing IN PM

Planned for major overhauls Needs study in view of our congested burner configuration

On going Inspection of furnace done before boxing up

On going

On going IN PM


5/10

Action Plan for Reduction of Boiler Tube leakage (BTL)

Area Action Plan

General Stringent Test of HP Welders

Avoid Gas cutting of tubes

Proper Edge Preparation

Proper Storage of TubesImprovement of radiography quality

S- Panel Inspection & DP of attachments during overhaul

Through cleaning of S-panels. S-panels bottom, and side wall 90 deg bends

by HP jet pump

Thickness survey of S-Panel

Checking of field welds/replacement

Deformed tubes

Thermal expansion/constraints and checking

DP checking/inspection of Dead Chamber

DP of attachments

Replacement of affected tubes

Providing new scallop bars & protection plates

Erosion Failures Replacement of eroded tubes

Sheilding of tubes

Wire mesh protection for end coils

100% radiography

Supervision during joint preparation & fit up

Radiography of old joints and rectification if anyProcurement of new coils with 100% weld joint radiography

Hardness testing of tubes

Inspection of supports

Replacement of affected tubes & bends

Inspection of wrapper tubes & intersections

Reheater Extensive thickness survey & dimensional check

Inspedtion of DMW joints

DPT of safe end tubes

Metallography of tube material to asses creep damage

Reheater Tie up

lug up

attachment Inspection of fluid cooled spacer tubes & attachments

Extensive thickness survey & dimensional check

Replacement of eroded tubes

Inspection of bends in Diamond panels

Cutting tubes samples in high heat zones for analysis

Seal trough

attachment &

Scallop bar

Eco weld joint

failure

Eco erection

weld jointfailure

Platen SH bend

Burner zone


6/10

Economizer Thickness survey of upper economizer & inspection (SCW)

Thick ness survey of eroded bends & replacement

Replacement of erosion sheilds

Inspection Eco inlet header stubs for FAC

Inspection of baffles, replacement of eroded & damaged sections

Replacement of eroded and mis-aligned tubes

Visual inspection of tubes in HRSB/LRSB areasPlaten Roof Inspection of attachments

Inspection of coil supports

Radiography of old erection joints and rectification if any

Replacement of eroded tubes and bends

Replacement of erosion sheilds

Visual inspection of tubes in HRSB/LRSB areas

Water wall Extensive tube thickness / replacement of eroded tubes

(Spiral &

Vertical) Radiography of old erection joints and rectification if any

Inspection of Transition header - thickness survey

Superheater DP of attachments

Thickness survey

DP of DMW joints

Riser/Sat.Steam

/Supply pipes Radiography of old joints

DP of vents/drain stubs

DP of socket welded joints in piping

Replacement of piping based on thickness survey

Power cycle pipi Removal of insulationn & DP checking

Thickness survey & replacements if anyReplacement of damaged erosion sheilds

Roof tubes Inspection of tubes

Seal plates/EJ Inspection, repair if any

Pent House Inspection of headers (non insulated)

Inspection of vents & supports - repairs if any

Boroscopy of Headers

Handers Comparision of Hot & Cold settings

Replacement of Broken tie rods

Chemistry Water & steam cycle parameters maintained limits

Drains/Vents

Hangar Tubes

LTSH


7/10

Measures

IBR Certification

CGPL Quality Certification

Not in WI for BTL

Inspection by Quality

Done by stores as per guidelinesNumbering of joints

Replacement/rebuid

Inspection/DP of hanger support

As per inspection

As per inspection

Not considered at present

Part of WI for BTL

Part of WI for BTL

As per inspectionNot considered at present

Replacement if any indication is

found


8/10

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspection

Based on inspectionBased on inspection

Based on inspection

Based on inspection

Based on inspection

Correct if any

Based on inspection

Based on inspection


9/10

Remarks

All pressure parts are cut by low heat input method

Wherever possible edge prepartion done on lathe with proper angles

Adequate preventive measures to ensure weld quality

100% DP of attachment welds

HP washing covered in outage scope

Extensive thickness survey/LFET planned

In inspection plan

based on inspection

In inspection plan

In inspection plan

In inspection plan

In inspection plan

In inspection plan

No erosion as per findings during short outages

In inspection plan

In inspection plan

In inspection plan

In inspection plan

In inspection plan

In inspection plan based on findings




In inspection plan

In inspection plan

In inspection plan

In inspection plan


10/10

In inspection plan

In inspection plan

In inspection plan

In inspection plan

In inspection plan

In inspection plan

In inspection plan

In inspection plan

LFET planned

on sample basis

in inspection plan

in inspection plan

in inspection plan

in inspection plan

in inspection planin inspection plan

in inspection plan

in inspection plan

Optional - if required

Compare with readings at time of commissioning

guidelines for btl

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