training r&m of boilers

7/31/2019 Training R&M of Boilers

1/45

23 May 2012 PMI Revision 00 1

Renovation &

Modernisation of

Boiler


2/45


When to do R&M of Boiler?R&M of Steam Generator is to be taken up under thefollowing conditions:

1.The unit has logged more than 200,000 hours of operation,i.e. its design life

2.RLA report has indicated requirements of major

replacements

3.The boiler is failure prone; e.g. frequent tube leakages

4.The boiler is not able to generate rated load

5.There is major off design performance; e.g. high metaltemperatures, high flue gas exit temperature, high unburntcarbon

6.On grounds of environmental or safety considerations


3/45


Inputs for R&M

1.Condition Assessment (CA) & Residual LifeAssessment (RLA) Studies

2.Thermal Performance Test (TPT), If Necessary


4/45


CA & RLA Studies


5/45


Intent of RLA

Restoration / up-rating of Generation capacity on a

continuous, safe and reliable basis. To increase unit availability and reliability on Sustainable

basis to meet the current requirements like ABT.

Achieving rated or better efficiency of the unit so that the

COG remains competitive. Achieving an extended competitive plant-life of another 15

years at least.

To improve safety of plant and personnel.

To meet current statutory and environmental norms.


6/45


CA & RLA

REVIEW OF OPERATIONAL HISTORY OF EQUIPMENTS:

Details of start up and Shut down Operational Regime Maintained Duration and extent of parameter escalation

Steam temperature and water Chemistry Observation During Planned Shut downs Replacements during routine maintenance and forced

outages Detailed Metallurgical Analysis

Analysis/Reports on premature failures


7/45


CA & RLA

Pre Outage Planning and Survey: Record nameplate details & general description of all

equipments Compilation of design details Review of these compiled data and assess the present

condition of equipment /system

Hot Walk down Survey Survey of the equipment / system while in operation Reference marking to be made in piping system, hangers &

supports, buckstays,etc Identify and prepare a list of missing items in equipment /

system

Cold Walk down Survey Inspection for detection of any visible abnormalities Measurement of steam flow path, thermal clearance, fitting

clearance, etc


8/45


CA & RLA

Visual Examination: To detect signs of overheating of tubes, for swelling, blistering

and warping To identify signs of corrosion or erosion To examine convection pass tube banks for detection of

misalignment of tubes To assess condition of all headers for ligament cracks etc. To determine the condition of components in the penthouse

including header supports and structural members To determine boiler setting integrity Examination of drum internals

Dimensional Measurement:

The components liable for deformation or distortion due towear / creep namely, headers, pipes, hangers, supportstructures etc. are to be thoroughly cleaned and dimensionsto be measured to compare with original / previous record.


9/45


CA & RLA

Videoscopic Inspection:

Videoscopic examination of all header internals. Digitalphotographs are taken of each header internal surface andeach header / stub connection. Videoscopic examinationdetermines the following:a) Internal cracks on headers/nipples/stubs/ ligamentsb) Condition of internal cleanliness

c) Oxide scale

Non-Destructive Tests: Dye- penetrant Examination (DPT) Dye-penetrant examination using fluorescent dye are used for

detection of surface crack / porosity / discontinuity of headerligament joints, pipe weld joints, attachment weld joints, valvebody / spindle / seal etc.


10/45


CA & RLA

Non-Destructive Tests(Contd.): Magnetic Particle Inspection (MPI)

Magnetic particle inspection using wet fluorescent methodshall be employed for detection of surface and sub-surfacecrack / discontinuity of header ligament joints, pipe weld

joints, attachment weld joints, valve body / spindle / seal etc.In case of detection of any crack, the depth shall bemeasured with the help of crack depth meter based on

electrical potential drop principle or ultrasonic principle

Ultrasonic Examination (UT) Ultrasonic Examination method shall be employed for

detection of sub-surface crack, loose bonding, stress crackingor any kind of discontinuity mainly in the longitudinal and

circumferential seams of the boiler drum, girdling loops of allhigh temperature tube panels, butt weld joints, attachmentwelds and stub joints of the steam & water headers & pipesetc.


11/45


CA & RLA

Non-Destructive Tests(Contd.): In situ oxide scale measurement

It is a high frequency ultrasonic method which is to be carriedout at various locations, especially in the tubes where themetal temperatures are maximum, in the platen & finalsuperheater and reheater assemblies.

Furnace Corrosion & Thickness Mapping

Continuous tube OD scanning method based on lowfrequency electro-magnetic principle to carry out the detailthickness and corrosion mapping of all the accessible tubesin the furnace zone

Metallographic Replication (RPL)

Metallographic examination by portable optical microscopeand surface replication technique are carried out to assessthe present microstructure condition of the componentssubjected to damage due to creep, temper embrittlement,stress corrosion cracking and thermal fatigue (low cyclefatigue).


12/45


CA & RLA

Non-Destructive Tests(Contd.): Hardness Testing

Hardness testing of tubes, weld joints, headers, pipes etc. arecarried out, wherever required, to ascertain any change inmetallography and to find out residual stresses. Hardnessmeasurement are to be compulsorily taken at the spots wherereplica has been taken

In-Situ Chemical Analysis (CA) In-situ chemical analysis is to be employed for determining

and categorizing the steel grade of various superheater andreheater coils with the help of instruments based on eitherOptical Emission Spectroscopy (OES) principle orradioisotope excited x-ray fluorescence analyzer.


13/45


CA & RLA

Destructive Tests: Tube samples and tube deposits from various boiler locationsalong with boiler drum deposit are collected for destructivetests. These are analyzed at reputed laboratories for:

Stress rupture test for mechanical properties Microstructure evaluation to find out metallurgical degradation

Chemical analysis of deposits


14/45


After collection of the various data asdiscussed and analysis thereof remaining

life of the boiler is calculated &recommendations are given accordingly.


15/45


Thermal Performance Test

The broad objectives of the TPT can be summarized as

follows: To evaluate the present thermal efficiency of the unit

To establish the steam, water and flue gas temperatureprofile and heat balance over different sections of theboiler

To establish flue gas velocity profile over differentsections of the boiler

To establish excess air and air ingress levels at differentsections in the boiler, particularly air heater leakage.

To analyze the data collected and compare withpredicted performance data

To identify shortfalls in performance and causes for thesame.


16/45


R&M of Boiler


17/45


Boiler Downtime Matrix(A typical case)

Pressure Parts Failure Pattern of a Typical

Boiler

Re heater

13%

Sec. Conv.Sections

8%Water Wall

11%

Economiser

26%

Pri S/H7% Platen S/H

7%

Sec S/H

28%


18/45


Interactive IssuesCoal Quality

Deterioratio

Mill

Capacity

Coal

Requirement

Higher

Economizer

erosion

Burner

Effectiveness

Reduced

Boiler

Efficienc

Steam

Throughput

Tube Metal

Tem .Hi h

Tube Failures

Major Boiler Issues

Secondary

Combustion

Air Ingress

Air Preheater

Erosion

Secondary

S/ H & other

Pr. Parts

Gas Temp.

High

PA Fan

Capacity

SA - PA Air

Mismatch

Flue Gas Velocities

Higher

Reheater Temp.

Control Dampers

Gas Q uantity High

C S


19/45


Issues PoorAvailability /

Reliability

Lower Efficiency Inadequate

Steaming

Parameters

Higher Generation cost Increased Emission

Levels & SPM

Areas * Pr. Parts * Operating

Parameters

* Milling System * Operation &

Maintenance practices

* ESP

* Spares

Inventory

* Boiler Losses * Health of Pr. Parts * Turbine steam demand * Burners

* Fan Margins

Reasons * ObsoleteTechnology

* Higher unburnt * Coal Quality * Unavailability of genuine

spares / OEM spares

* Completed

Design Life

* Increased

Moisture in coal

* Air Ingress * Quality of spurious

spares

* Increase dry gas

loss / air ingress

*Ageing of Pr. Parts * Design deficiency in

Turbine

* Wear & Tear of

Components

Remedies * Replacement /repair of worn out

parts

* Replacement of

furnace with

membrane panels

* Milling system

upgradation

* Switch over to new

technology

* Addition of more fields in

ESP

* Pent house

sealing with

* Replacement of Pr.

Parts with new design

* O&M Management

system

* Increasing the height of

fields / adding parallel

*Turbine Retrofit * Installtions of improved

burners / Low Nox burners

Achievements

post R&M

* Increased

avalbty.

* Improved

Efficiency

* Restoration of

Design Parameters

* Reduced downtime and

maintenance

* Reduced emission levels

* Improved PLF &

PUF

* Reduction in generation

cost

* Life extension

Issues, Causes & Solution


20/45


Issue Life ExtensionComponent Typical

Life

LimitingFactor

Lead TimeFor

Ordering

Outage Requiredfor Installation

Headers-Superheater &

ReheaterPipes MS &RH

Creep ,Thermal

fatigue

2 3 years 13 weeks (largeheaders),6-9

weeks (smallheaders)

Tubes-Furnace

wall,Superheater &Reheater

Fireside

corrosion,Creep,overheating

18 months 10-12 weeks (for

completesuperheater orReheater units)


21/45


Issue Life Extension

Component Typical

LifeLimitingFactor

Lead Time

ForOrdering

Outage Required

for Installation

Tubes

Economisercoils, S-paneletc.

Ash

erosion

18 months 10-12 weeks (for

completeEconomiser, Spanel etc.)

High Pressure

Valves

Creep ,

Thermalfatigue

18 months 3-4 weeks


22/45


Issue: Inadequate SteamingParameters

AREAS

Milling System Health of Pressure Parts Fan Margins System/ Process / Turbine demand

continue


23/45



Reasons Restricted mill capacity to handle the increased coal

demand due to poor coal quality

Poor health of Pr. Parts not permitting operation at

the rated parameters / capacity

Inadequate fan margins to cater increased coaldemand

Lower system demand

Continue


24/45



Remedies Up gradation of Milling system

Re- Design of Boiler / Replacement of Pr. Parts withimproved design taking advantage of improved

technology & materials Replacement of tangent / spaced tube construction

with membrane panel

Repair / Replacement / upgradation of Fans

Arresting air ingress Addition of heating surface in equipment like

economizer and APH

continue


25/45


Issue: Low Efficiency

Areas

Improper design of boiler

Milling System

Burners

Air Preheaters Furnace sealing


26/45


Issue: Low EfficiencyReasons

Improper heat pick up design resulting in high exitflue gas temperature

Operational restrictions like metal temperaturerestrictions causing loss of Rankin efficiency

Poor coal fineness due to milling systemunderperformance

Improper mixing of air & fuel in burners resulting incarbon loss

Poor performance of air preheaters resulting in highflue gas exit temperature (FGET)

Air ingress into the furnace leading to high flue gasloss


27/45


Issue: Low EfficiencyRemedies

Redesign of boiler pressure parts based on TPTresults: Addition / deletion of heat transfer surface invarious pressure parts sections / APH

Change in metallurgy to allow higher tube metaltemperatures

Upgradation of milling system

Improved burner design

Renovation of furnace sealing including penthouse

Upgradation of Fans if Fans are underperforming


28/45


AREAS & CAUSES

Poor coal quality Combustion Technology Burners and operating

constraints on fans

Fuel fineness Milling capacity & internals ESP Sizing constraints due to fuel quality Continue

Issue: Increased Emission & SPM


29/45


Issue: Increased Emission & SPM

REMEDIES

Installation of Low Nox Burners ESP

Addition of new fields in ESP Increasing the height of existing fields

Addition of parallel stream Installation of latest controllers like EPIC II Introduction of Bag filters

ACHIEVEMENTS POST R&M Reduction in the Nox level Reduction in particulate matter


30/45


A Case Study:

R&M & LEP - DPL, Durgapur


31/45


R&M & LEP - DPL, Durgapur

DPL has 5 boilers (2 x 30 MW and 3 x 75MW) whichare almost 30 years old. The boilers were unable toachieve the rated parameters, mainly due to thefollowing reasons:

Deteriorated coal quality (High ash & Moisture, LowerGCV).

Improper combustion Ageing of boiler Pressure & non Pressure Parts.

DPL Durgapur


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DPL, Durgapur Major Objectives

Improvement in Boiler Efficiency

Restoration of Rated Evaporation

Restoration of Steaming parameters Arresting Air Ingress

Reduction in downtime

DPL D


33/45


DPL, Durgapur Major Activities

Super heater - Improved Metallurgy to cater theupset conditions during operation. BB tubes - leading tubes diameter reduced and

protective shield provided before and after cavity toreduce erosion.

Economizer Additional loops added to reducebackend. Erosion protection shield provided.

Tubular APH Ferrules at gas entry point to reduce erosion

Changing of Staggered tubes to inline (U#1&2) FD fan reconditioned, ID fan replaced to get required

margin.continue

DPL D


34/45


DPL, Durgapur Major Activities

Milling System

U#1 & 2 mills replaced with mills & PA fans ofunits # 3&4

3 nos. New mills provided for U # 3 & 4 (Oneold mill retained)along with hot PA fans

Reconditioning of suction mill of U#5 Mill loading reduced to 80% at Max. load to

take care of burner heat input New Civil foundation and PF pipes for all units

Wind Box New Wind Box of improved designprovided for all units.

DPL Durgapur


35/45


DPL, Durgapur Performance Post R&M

Performance of Boilers achieved during PG Test

Sl.

No.

Description Unit Guarante

ed

Achiev

ed

Guarante

ed

Achiev

ed

Guarante

ed

Achiev

ed1 Thermal Efficiency

(Corrected)

% 86.11 89.91 86.7 88.62 84.95 88.34

2 Steam Generation TPH 124.9 137.06 253 270.34 258 259.46

Boiler # 1 Boiler # 3 Boiler # 5


36/45


bl


37/45


Summary Table

Component Visual

Ultrasonic

testing

Mag

neticparticle

inspec

tion.

Liquid

Dye

Penetrant

inspe

ction

Replication

Sampling

Depo

sitAnal

ysis

Out

side

Dia-metre

and

thick

ness

Fibre

Opticinspec

tion

Hardness

Others

1 2 3 4 5 6 7 8 9 10 11 12

Drum (Steam) Yes Yes No Yes Yes No Yes Yes No Yes

Water drum Yes Yes No Yes Yes No Yes Yes No Yes

Low tempe-

rature headerYes No No Yes No No No Yes Yes Yes

Attempertion

headerYes Yes No Yes Yes No No Yes Yes Yes

Swell

measure

ment

High

temperature

economiser

tubes

Yes No No No No Yes No Yes No No

Low

temperature

economiser

tubes

Yes No No No No Yes No Yes No No

Convection

superheater

coils

Yes No No No No Yes Yes Yes No Yes

Primary

superheater

coils

Yes No No No No Yes No Yes No Yes

Non-

destructive

oxide

thickness

inspection


38/45


Prefinal

superheater

coils


Final

superheater

coils


Reheater

coils


High

temperature

headers

Yes Yes No Yes Yes No No Yes Yes Yes

Final

superheater

header


Swell

measure

ment

Reheater

headersYes Yes No Yes Yes No No Yes Yes Yes

Swell

measure

ment

Main steam

pipingYes No No No Yes No No Yes No Yes

Platen

superheater

header

Yes Yes No Yes Yes No No Yes No Yes

Primary

superheater

headers


Economiser

header Yes No No Yes No No No Yes No Yes

Auxilliaries Yes No No No No No No Yes No No

Boiler bank

tubesYes No No No No No No Yes No No

Waterwall Yes No No No No Yes No Yes No No

Furnace

waterwallsYes No No No No Yes No Yes No No


39/45


Sl.

No.Component VE DC ME & H TM DPT MPI UT / IOT

Visual

Examinatio

n

6 locations

along the

length

4 spots of

longitudinal seam

weld & 4 spots of

circumferencial

seam welds - 8

No.

6 locations

along the length

On two

longitudinal

and four

circumferencial

welds, at all

tap off stub

joints

(sat.steam-

raiser tube dia

127 mm stubs

: 89nos.,safety

valve -6, Down

comer-6, Feed

nozzle-3 &

other tap off-

34

FMPI on two

longitudinal

and four

circumferencial

welds.

MPI at(sat.steam-

raiser tube dia

127 mm stubs

: 89nos.,safety

valve -6, Down

comer-6, Feed

nozzle-3 &

other tap off-

34)

On two

longitudinal and

four

circumferencial

welds, at all tap

off stub joints/Butt joints

(sat.steam-raiser

tube dia 127 mm

stubs :

89nos.,safety

valve -6, Down

comer-6, Feed

nozzle-3 & other

tap off-34)

6 locations 8 locations 6 spots 144 welds 144 welds 144 welds

Visual

Examinatio

n

At burners,

soot blowers,

bottom ash

hopper, Z panel

and goose

neck area

at burners, soot

blowers, bottom

ash hopper, Z

panel and goose

neck area on 10

tube samples

at burners, soot

blowers, bottom

ash hopper, Z

panel and

goose neck

area

At twentylocations

attachment

welds at

burners, wind

box, wall

blowers at

accessible

locations

At accessible

locations -20

tubes

10 Samples 1000 spots At 20 locations

Visual

Examinatio

n

On all water

wall hanger and

screen tubes

One sample each

from hanger tube

& screen tube

At six locations

along the length

on attachment

welds at

random

236 tubes 2 samples 1416 spots 10 locations

1

2

3

500 MW BOILER - RESIDUAL LIFE ASSESSMENT - EXTENT & QUANTUM OF TESTS

Water wall

Water wall

hanger &

Screen Tubes

Steam Drum


40/45


Visual

Examinatio

n

3 locations

along the

length for each

header

Total -4 Nos10 locations

along the length

on 8

circumferencial

welds

on 8

circumferencial

welds

on 8

circumferencial

welds

12 locations 4 locations 10 locations 8 welds 8 welds 8 welds

Visual

Examinatio

n

W.W outlet -

8, SCW outlet-

6, Raiser tubes-

20

Hardsness on

46spots,Replicas

SCW -4, WW- 2.

10 locations

along the length

On

circumferencial

welds at WW

outlet -12,

SCW outlet-9,

Raiser tube -

20, & Stubs &

lugs: 150 Total

191 Nos.

On

circumferencial

welds at WW

outlet -12,

SCW outlet-9,

Raiser tube -

20, Total 41

Nos.

On

circumferencial

welds at WW

outlet -12, SCW

outlet-9, Raiser

tube -20, Total 41

Nos.

34 locations

Replica-6 spots

Hardness-46

spots

10 191 welds 41 welds 41 welds

Visual

Examinatio

n

on two tube

samples

on attachment

welds at

random

2 Samples 20 locations

Visual

Examinatio

n

Eco inlet

header - 3 ,

Eco outlet

header - 3

Eco inlet header -

2 , Eco outlet

header - 2

Eco inletheader - 2,

Eco outlet

header - 2,

Eco outlet

tubes - 6

On

circumferencialwelds at Eco

inlet - 4, Eco

outlet -6, Eco

Header stubs

& gamma

plugs-100 Nos

at Random

On

circumferencialwelds at Eco

inlet - 4, Eco

outlet -6, Eco

Header stubs -

100 Nos at

Random

On

circumferencial

welds at Eco

inlet - 4, Eco

outlet -6,

6 locations 4 welds (min)10

locations(min)110 welds 110 welds 10 welds

4

5

6

Water wall

ring headers

Water wall

outlet

headers,

steam cooled

wall headers

and riser

tubes

Economiser

assemblies

Econimiser

inlet and

outlet header

7


41/45


Visual

Examinatio

n

one tube on

each coil -118

Nos

at two locations

by sampling

on all coils

along the length

at six locations -

1416 Nos

on all

attachment

welds near roof

and crown

plate welds at

Random 20%

Internal oxide

scale

measurement

covering all coils

and terminal

tubes (Top &

Bottom

elevations) - 708

s ots

118 tubes (min) 2 samples 1416 spots(min)

25 crownplates of 6

tubes each

708 spots

Visual

Examinatio

n

6 locations

along the

length at LTSH

outlet Header

LTSH inlet -2

,LTSH Outlet -2

LTSH inlet -2,

SCW inlet - 4

On

circumferencial

welds at LTSH

inlet -2, LTSH

outlet -4 and

gamma plugs.

Stubs :

200nos.

Circumferencia

l welds at

LTSH inlet -2,

LTSH outlet-4

Circumferencial

welds at LTSH

inlet -2, LTSH

outlet-4


Visual

Examinatio

n

6 locations

along the

length

Replica-2Nos6 locations

along the length

Circ.weld:Desu

perheater-

8,spray tube -

2, thermowells -

6,100% on all

liner bolt welds

& gamma plug

Desuperheater-

8,spray tube -

2, thermowells

-6,100% on all

liner bolt welds

& gamma plug

Circ.weld:Desupe

rheater-8,spray

tube -2,

thermowells -6


Visual

Examinatio

n

Radiant roof

headers -2,

LTSH support

header -4, Eco

support header -

8

Radiant roof

headers -2, LTSH

support header -

2, Eco support

header - 2

Radiant roof -

4,LTSH support

header 4, Eco

support header -

8

Radiant roof -

7,LTSH

support

header/ Eco

support header

-8 & Stubs :

200nos.

Radiant roof

header-7,LTSHsupport header-

4,ECO support

header-8,

Flourscent

MPI on Eco

support header

stub-1096 stub

joints

Radiant roof -

7,LTSH support

header 4, Eco

support header -8

14 locations 6 locations 16 lcoations 215 welds1120 welds

(min)19 welds

LTSH coils

and terminal

tubes

LTSH inlet

and Outlet

header

LTSH

Desuperheate

r links

11

Radiant roof

header,

Economiser

and LTSH

support

headers

8

9

10


42/45


Divisional

superheater

panels

Visual

Examinatio

n

On all panels-

444 Nosby sampling -

on all the six

panels- 888

Nos including

bends at pent

house

on DMW

joints, roof seal

band weld and

crown plate

welds at roof at

Random 20%.

in penthouse

at identified

locations

1.Institu oxide

scale

measurements

covering all

panels 400 spots

in penthouse& in

furnace. 2. UT of

girdling loops 12

No. for checking

stress cracking

444 tubes 2 samples 888 spots

50 butt

welds,crown

plates of two

panels

444 bends400 spots & UT

of 12 girdling loop

Visual

Examinatio

n

On all panels -

432 Nos

by sampling-2

Nos

on all tubes and

covering all

coils-864 Nos

on DMW

welds, roof

seal band

welds, crown

plate welds at

roof and

attachmentwelds -

Random 20%

Insitu oxides

scale - 200 Nos,

on 24 girdling

loops for stress

cracking and 6

binding loops

432 tubes 2 samples 864 spots

30 butt welds,

crown plates of

6 panels

230 locations

Platen

superheater

inlet and

outlet headers

VisualExaminatio

n

6 locations

along the

length,

including swell

measurements

outlet header -

4, inlet header -

2

SH InletHeader -2,SH outlet

Header -4

SH InletHeader -2,SH outlet

Header -4

A)On 200 stub

jointsB)Circumf

erential weld at

Inlet header -6,

outlet header-

10, SHDP toplaten

connection-5,

Drains and

vents stub-4

and gamma

plugs

A)On 200 stub

jointsB)Circum

ferential weld

at Inlet header -

6, outlet

header-10,

SHDP to

platen

connection-5,

Drains and

vents stub-4

and gamma

plugs

A)Circumferential

weld at Inlet

header -6, outlet

header-10, SHDP

to platen

connection-5,

Drains and vents

stub-4 and

gamma plugs

6 spots 6 spots 6 spots 225 welds 225 welds 25 welds

13

Platen

superheater

coils

12

14


43/45


Visual

Examinatio

n

Final RH -736,

HalfRH- 184,

covering all

panels

by sampling-6

Nos. Hardness

measurement on

Final RH coils :

100 nos.

Final RH-1472,

Half RH- 1472

covering all

panels

On 50 DMW

joints,

attachment

welds and

crown plate

welding 20% at

random

on girdling loops

for stress

cracking at

random , Insitu

oxide scale

analysis 1400

points

920 tubes

6 samples and

100 hardnessspots.

2944 spots

50 butt

welds,crown

plates of 10panels of full &

half RH

1400 locations

Visual

Examinatio

n

Division Panel

inlet-12, DP

outlet-12,Wall

RH inlet-2,RH

Platen inlet-

14,RH outlet-4,

RH links-4

Div.SH Inlet : 2 &

Outlet : 2

RHInlet header-4 ,

outlet -4

Division Panel

inlet-12, DP

outlet-12,Wall

RH inlet-2,RH

Platen inlet-

14,RH outlet-4,

RH links-4

On circ. weld

joints at SHDP

inlet -6, SHDP

outlet-8,Wall

RH inlet-4,RH

Platen inlet-

12,RH outlet-

10 and 400

nipple welds &

gamma plugs

On circ. weld

joints at SHDP

inlet -6, SHDP

outlet-8,Wall

RH inlet-4,RH

Platen inlet-

12,RH outlet-

10 and 400

nipple welds &

gamma plugs

On circ. weld

joints at SHDP

inlet -6, SHDP

outlet-8,Wall RH

inlet-4,RH Platen

inlet-14,RH outlet-

12

36 spots 12 spots 36 spots

40 butt welds

and 400 nipple

welds

40 butt welds

and 400 nipple

welds

44 butt welds

Visual

Examinatio

n

Minimum one

on each

integral piping

Replica-2 Nos

Minimum one

on each integral

piping

At

circumferential

welds

At

circumferential

welds

At circumferential

welds

12 locations 2 spots 12 spots 12 welds 12 welds 12 welds

Visual

Examinatio

n

MS -4 Nos

At SH connecting

link-2 Nos, MS

piping from boiler

to stop valve-

4Nos

MS -4Nos

MS-4,

Thermowell

stub-4, safety

valve / ERV

stub -14

MS-4,

Thermowell

stub-4, safety

valve / ERV

stub -14

MS-4,

Thermowell stub-

4, safety valve /

ERV stub -14


18

Boiler integral

piping(alloy

steel including

MS upto stop

valve)

17

Boiler integral

piping (carbonsteel) and

down comer

15

Reheater

Panels-Final

Reheater,Half

Reheater

16

Divisional

superheater

headers and

reheater

headers (

inlet,

intermediate

and outlet

headers)


44/45


Visual

Examinatio

n

MS-6,HRH-

14,CRH-5,Feed

water-2

,Suction

manifold-3, CC

pump

discharge-6

,Eco links- 6

At three spots on

each piping -18

Nos

MS-6,HRH-

14,CRH-5,Feed

water-2

,Suction

manifold-3, CC

pump discharge-

6 ,Eco links- 6

MS-6,HRH-

14,CRH-5,Feed

water-2

,Suction

manifold-3, CC

pump

discharge-6

,Eco links- 6

MS-6,HRH-

14,CRH-

5,Feed water-2

,Suction

manifold-3, CC

pump

discharge-6

,Eco links- 6

MS-6,HRH-

14,CRH-5,Feed

water-2 ,Suction

manifold-3, CC

pump discharge-

6 ,Eco links- 6


Boiler

Expansion

Visual

Examinatio

n

VE

DC

ME&H

TM

DPTMAGENETIC PARTICLE INSPECTION MPI

FMPI

UTRTFB

DA

20

19

,

Hot reheat

and cold

reheat piping

downcomers,

feedwater

piping, CC

pump suction

manifold &discharge

piping,

LEGEND

THICKNESS MEASUREMENT

DYE-PENETRANT TESTING

WET FLOURSCENT MAGNETIC

PARTICLE INSPECTION

DEPOSIT ANALYSIS

RADIOGRPAHIC TESTINGFIBRO SCOPE TESTING

VISUAL EXAMINATION

METALLOGRAPHIC EXAMINATION &

ULTRASONIC TESTING

DIMENSIONAL CHECKS


45/45

training r&m of boilers

Documents