Rev 5 Destressing of LWR -18.11.2022.docx

want to focus on destressing part briefly and it should be like official presentation and explain de stressing more .

1. Sensitivity: LNT Construction Internal Use
517.11.2022
Simranjeet
Singh
Satish
A.K. Jain
Assistant
Engg. Manager
Engineering
Manager
Track Head
1SEQUENCE OF OPERATION FOR DE-STRESSING
Neutralization of the stresses (de-stressing) in the rails will be carried out after the 3
rd
round of tamping.
Figure 9-1. Destressing of LWR Track by FBW Cum De-stressing Machine & Super Puller
Sequence of Operation:-
1)Destressing shall be carried when prevailing temperature is less than stress free temperature.
2)Destressing operations shall be started from J1-J2 panel.
3)Anchor length shall be calculated as 2.5 (to-tp) which is J1-A and fastening of J1-A will remain
intact.
4)Clamp rails in puller pull rails together several times and release to stretch unclipped rail section
for correcting misalignment etc.
5)Marker pillars shall be erected on either sides at the location A & B of the track and the marking
shall be transferred on the rail foot at A.
6)The fastening of panel J1-J2 shall be removed starting from J2 and proceeding towards A.
7)Panel J2-A shall be mounted on the roller starting from J2 & proceeding towards A.
8)FBW cum destressing machine shall be stabled at J2 end of the panel J2-J3.
9)Extension required for the length J2-A shall be calculated by FBW cum destressing machine
depending upon the stress free temperature, prevailing temperature, length of the panel to be
destressed and considering the rail to be consumed during the welding for which the required
input details shall be fed into the machine.
10)The required gap calculated by super puller (as shown in Clause 8 above) will be provided at J2.
11)Clamp rails in puller pull rails together several times and release to stretch unclipped rail section
for correcting misalignment etc.
J1
J4 J5A J3 J6J2
25m long rail1 km LWR
Turnout
B
Anchor length
100 m
100 m

2. Sensitivity: LNT Construction Internal Use
12)Calculated stretch force by the machine will be applied by the super puller on panel J2-A and
flash butt welding shall be done at J2.
13)Unmount the panel A-J2 and fasten rails to the sleepers.
14)If any movement is noted at A (anchor length) necessary corrective action will be taken for
increasing the anchor length.
15)Marking at B shall be transferred to the rail foot.
16)Now the destressing of panel A-J2 is complete.
17)Destressing of J1-A (Anchor length + 100m) shall be done at the time of welding of J1 after
destressing of switch & crossing/ adjoining track.
After the destressing of A-J2 is completed, the destressing of the next panel J2-J3 shall be taken
up and is as below:-
i.Track in rear of B will be marked as anchor length and marker pillar will be provided.
ii.The FBW cum destressing plant shall be shifted to J3 of the J3-J4 panel.
iii.The necessary gap at J3 shall be created as explained above in point no.8 but the
length to be de-stressed considered is B-J3.
iv.The above stated steps shall be repeated and welding of J3 shall be done. This
process shall continue till the end of the block section.
v.Before doing the calculation of extension, it shall be kept in mind that if the
movement at marker pillar of anchor length is noticed, corrective action shall be
taken.
NOTE: The Destressing of one rail shall be done at a time for J1-J2 panel and after completion of
above explained process for J1-J2 panel, the other rail i.e. panel J1-J2 shall be destressed in the
similar manner. Similar process shall be followed for the subsequent panels.
2DESTRESSING OF LWR TRACK BY FBW CUM DE-STRESSING MACHINE
AND SUPER PULLER
10.1 HOLLAND H1000 WELDER WITH 160 T PULLER OPERATING SEQUENCE:-
1.ARRIVE TO DE-STRESSING LOCATION IN TRACK
2.HAVE INFORMATION ON AREA NT
3.MEASURE ACTUAL RAIL TEMPERATURE T. INSURE T IS BELOW OR EQUAL TO NT TO PROCEED
WITH DESTRESSING. ENSURE THAT WEATHER IS ADEQUATE TO KEEP T≤ NT FOR ABOUT ONE
HOUR.
4.MOVE UNCLAMPED TRACK ASIDE TO LOCATE PLUG
5.LOCATE PLUG IN TRACK TO MAKE FIRST WELD.
6.LOWER WELDER WITH PULLER ON TRACK IN LOCATION OF FIRST WELD
7. DISCONNECT PULLER FROM WELDER AND MOVE WELDER ASIDE
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3. Sensitivity: LNT Construction Internal Use
8. GRIND RAILS IN CLAMPING AREA TO BARE METAL
9.CLAMP RAILS IN PULLER
10. PULL RAILS TOGETHER TO GAP ABOUT 2 MM
11.PRE-ALIGN RAILS BY PULLER
12.COMPLETE FIRST WELD. WELD RECORDING WILL START AUTOMATICALLY WITH WELD START
13. LOAD TENSION WELDING PARAMETERS TO PLC
14.TYPE OPERATOR NAME
15.TYPE LOCATION – GEOGRAPHICAL, TRACK KM, CHAINAGE, ETC.
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4. Sensitivity: LNT Construction Internal Use
16.SELECT RAIL SIZE – QUANTITY IS UNRESTRICTED
17.INPUT NT FOR THE AREA
18.INPUT ACTUAL RAILS T
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5. Sensitivity: LNT Construction Internal Use
19.INPUT LENGTH OF UNCLIPPED RAILS
20.CLICK “OK” AND COMPUTER WILL SHOW READY TO WELD MONITOR
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6. Sensitivity: LNT Construction Internal Use
21.RELEASE PULLER FROM RAILS AND LIFT WELDER/PULLER TO TRAVEL POSITION
22.CLIP WELDED PLUG TO SLIPPERS
23. MOVE OTHER SIDE OF TRACK TO PLUG
24.CUT LONG RAIL END TO PROVIDE 18 MM GAP BETWEEN RAILS IN WELD AREA
25. MOVE RAIL AFTER CUT TO PLUG END
26.LOCATE WELDER AND PULLER OVER SECOND WELD
27. DISCONNECT WELDER FROM PULLER AND MOVE WELDER ASIDE
28. CLAMP RAILS IN PULLER. PULL RAILS TOGETHER SEVERAL TIMES AND RELEASE TO STRETCH
UNCLIPPED RAIL SECTION
29.MEASURE IF GAP BETWEEN RAILS IS STILL 18 MM. CORRECT (CUT RAIL END) IF REQUIRED.
30. PUSH “RECORD” BUTTON ON PULLER CONTROL PANEL.
31. PULL RAILS TOGETHER TO 1…2 MM GAP
32.PREALIGN RAILS BY PULLER
33.LOWER WELDER ON RAILS AND CLAMP RAILS IN WELDING HEAD
34.COMPLETE WELD
35.UNCLAMP WELDER FROM COMPLETED WELD, LIFT AND MOVE ASIDE
36.KEEP RAILS CLAMPED IN PULLER FOR ABOUT 8 MINUTES TILL WELD TEMPERATURE WILL BE
BELOW 700ºF (370ºC)
37.LOWER RAILS ON SLEEPERS AND UNCLAMP PULLER
38.GENERATE WELDING CHART FROM UNIT PC ON COMPLETED DE-STRESSING WELD
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7. Sensitivity: LNT Construction Internal Use
3CREEP POST
It is ensure that proper creep posts/reference posts will be erected at every km & corresponding creep
mark are marked on non-gauge face side of rail heads for inspection and monitoring behaviour of CWR.
4LONG WELDED RAIL (LWR) SIGN BOARDS:
As per the IR & International practice LWR boards will be provided at the location of all the SEJs.
Indicative LWR board is depicted below.
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8. Sensitivity: LNT Construction Internal Use
5 GENERAL SAFETY PRECAUTIONS
1.No unauthorized person may operate this machine.
2.Do not operate this equipment unless technically qualified.
3.Always wear a hard hat when working around the MobileWelder®, Pullertruck and Support
Equipment.
4.Always wear safety glasses with side shields around the work site. When grinding rail, a full-face
shield should also be worn to protect the operator from flying debris.
5.Wear either safety glasses with side shields, or a face shield when standing or working near the
welder head during the welding operation. Weld flash can be thrown six to ten feet beyond the
welder flashing area.
6.Wear welding goggles, or a tinted face shield during the welding cycle, when looking at the
flashing of the rail.
7.All personnel must wear approved safety shoes when at the work site. Also wear long sleeved
shirts, long pants (no cuffs).
8.Only the crane operator should be near the welder or 160T Puller, during crane operations. The
crane operator cannot see around all sides of the equipment, and may swing the load before
everyone is clear of the area. This could pose a hazard to nearby personnel.
9.Always be aware of potential shock hazards when the equipment is operating. Only
qualified, trained personnel should work on any of the electrical circuits.
10.Personal injury Hazard: Do not stand inside the 160T Puller, or between it and the sides of the
welder, severe personal injury could result from the welder trapping a limb against a rail. The
welder weighs 6,000 pounds.
11.When working on electrical circuits, shut down the equipment and tag it to prevent
accidental start-up. Observe all appropriate precautions to prevent shock and injury before
entering any cabinet or control enclosure.

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9. Sensitivity: LNT Construction Internal Use
6DE-STRESSING OF TRACK AT SPECIFIC LOCATIONS
6.1GLUED INSULATED JOINTS:
1)No Glued insulated joints are envisaged in WDFC.
2)Glued insulated joints if provided shall be located at Junctions / connections with Indian
Railways.
6.2BRIDGES
Guard rails shall normally be fixed after de-stressing. No special precautions are required, while
carrying out the de-stressing over the ballasted decks. Care shall, however, be taken for safe working
of staff while on the bridge.
7SHE MANAGEMENT
SAFE WORK METHOD FOR DE-STRESSING OF LONG WELDED
RAILS .
Document No. : De –Stressing of Long welded Rails / CTP 3R/ EHS/ HIRA/ 037 / REV.
00
Name of the Project : CTP-3R
Sl.
No.
List of Control Measures Action By
1 Entering & Working at site area in Summer
/Monsoon/Foggy Weather :-
Only SHE inducted & physically fit workmen shall be
engaged to do the activity.
All required PPEs shall be used by all.
Sufficient drinking water shall be made available at site.
Workmen shall be advised to drink enough water
frequently.
In the case of feeling any uneasy, workmen must
report to concerned supervisor.
Heat related safety precautions shall be explained to all
the workmen during tool box talk.
Temporary rest shed shall be provided near by the job
area.
Monsoon precautions must be explained to all workmen
during tool box talk.
Site Engineer
/Supervisor Site /
SHE Dept/ ADMIN
Dept
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10. Sensitivity: LNT Construction Internal Use
Dewatering arrangement shall be made readily available.
All electrical connection /system shall be checked prior to
starting the work
All electrical connection shall be taken through
RCCB/ELCB.
Damaged and worn-out cable shall not be used.
Electrical connection shall be done only by electrician.
Work shall not be carried out during drizzling/ raining.
Weather protection shall be made near by the job
location.
Proper precaution shall be taken to work in foggy
condition i.e.2, vehicle will move slowly, Fog light shall be
installed in all vehicle. Look out man shall be deployed at
conspicuous location for guiding the driver for train
movement.
2 Working nearby IR Track
All the safety precaution of working near running track shall
be rigorously followed as mentioned in the Method of
statement.
Prior to doing the job, the area shall be barricaded at least
6 metre from the centre of railway track.
No one shall be allowed to cross the railway track.
Look out man shall be deployed nearby working area with
flag and whistle, who will alert the workpeople for
movement of train.
Works which is executed within 3.5m from centre line of
existing Indian Railway track shall be executed under
block protection and with permit to work from concerned
railway.
For works to be executed between 3.5 m to 6 m from
centre line of existing Indian Railway track work to be
executed after erection of fencing as per approved plan
according to the Annexure IV of the safety document.
For works to be executed beyond 6 m from centre line of
existing Indian Railway track, it will be ensured that no
vehicle / construction equipment infringes demarcation
line marked at 6 m from centre of existing railway track.
All utilities, signalling cables, signalling equipment,
pipelines, gate lodges, staff quarters etc., coming in the
alignment will be shifted / relocated as per approved plan
before undertaking earth-work programmed.
During earth-work if any signalling cable not identified
earlier got damaged it should be immediately reported to
Railway and immediate action will be taken for repair of
the same to avoid interruption to traffic.
Any material unloaded along the track will be kept clear of
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11. Sensitivity: LNT Construction Internal Use
moving dimensions and stacked at minimum 3.5 m from
track centre of running track.
Movement of vehicle / working of machineries will not be
permitted during night. In case night working is to be
adopted proper fencing at 3.5 m from track centre of
running track will be erected to ensure that no
infringement of moving dimension takes place. Suitable
lighting arrangements will also be done.
Working in existing railway station area for modification of
existing siding / line will be done after approval of plan
and with permit to work from Railway.
Modification to road surface at existing level crossings
which may cause interruption to road traffic will be
executed as per approved plan with the approval of
concerned local authorities.
3 Conversion of 250m panels into 1 km long welded rails
This work shall be carried out by NTC Machine.
Welding of rail joints of the 250m panels in 1 km panels as
per Work procedure
The joint will be clamped with 1m long fish plate.
Work shall be carried out by only trained and experienced
operator.
 Only Trained person shall be engaged for this work.
All the rail shall be locked with sleeper.
Site Engineer
/Supervisor
4 Arrangement for doing pre-heating, flashing, forging
striping

Only approved quality of welding gadgets shall be used.
The welding work shall be carried out as per approved
welding procedure.
A programmable logic controller (PLC) shall be used to
control the weld process.
Proper holding, pulling & alignment shall be done by
experienced personnel only.
Check for any leakage in hydraulic system
Ensure Proper earthing done for welding machine .
All personnel keep safe distance away from flash butt
machine while operation.
Before welding, end faces of the rails to be welded and
electrode contact locations shall be thoroughly cleaned of
rust, paint etc. by brushing and grinding to bare metal
finish for good electrical contact to avoid arcing at the
contact points on the rail and to eliminate the possibility of
Site Engineer
/Supervisor
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12. Sensitivity: LNT Construction Internal Use
rail failure near joint due to Copper penetration and
formation of brittle “martensite” structure.
The electrical contacts, i.e. Copper electrode in the
welding machine must be cleaned by compressed air
pistol to ensure freedom from loose oxides and other
foreign matter so that no arcing takes place at the contact
points on the rail
 All electrical safety precaution shall be taken prior to
starting the welding work.
Wear necessary PPE (Welding hand gloves, Safety shoes
with rubber sole, full sleeve cotton shirt ,welding apron,
welders helmet with shield, leather hand gloves)
 It must be ensured that only certified welder should
operate the flash butt welding machineries
Do not hold hand or went closer to the rails when the rail
end faces are ready for welding which may leads to crush
injury
Welding operation shall not be carried out in wet condition
or during rains.
This work shall be carried out by only trained operator.
Alcohol consumption/ Smoking should be strictly
prohibited at site
Fixing of electrodes on the two Rails shall be done by only
trained operator.
Prior to doing the work,Flash butt welding machine must
be thoroughly inspected by P&M and SHE department at
regular intervals.
Display necessary warning signs as required
While doing welding no one shall be stand near the job
except welding crew.
 No flammable materials shall be kept near the job.
05 Cutting of molten slag and grinding and finishing of the
rail join surface
After completion of all the stages of Flash Butt welding
the top, side and bottom surfaces of rail head shall be
grind with the help of “Rail Profile Grinder” to achieve
the desired tolerances at the top table and sides of the
rail.
Don't touch the welded rails immediately when it was
came out of welded area
Don't block the conveyor line which allows the welded
rails to proceed to Rail stack yard
Only designated grinder shall be authorized to operate
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13. Sensitivity: LNT Construction Internal Use
grinding machine and he must not leave machine
unattended leading to unauthorized operations
Machine must be kept under safe & custody and place
shall be dry and protected from rain
Ensure wheel is correctly fitted and tight enough and
do test run the machine keeping away from body. Also
ensure work piece is firmly secured
Operator must use mandatory PPE's and task specific
PPEs such as eye protection, skin protection, ear
protection etc.
Ensure adequate fire prevention measures taken such
us work area is free from combustible materials,
electrical cables etc or moved away from hot work area
or these materials is sufficiently protected
Replace the wheel if the worn-out is exceed the mark
given in wheel and also replace even the event of low
height fall (say lm height), wet in drain or oil etc.
Ensuring that waste material is properly removed
segregated and disposed of.
All material, tools and equipment are kept in defined the
locations, in a tidy and controlled way.
Walkways are established and maintained that regular
housekeeping is carried out by the whole site team.
All stairways, passageways and gangways shall be
maintained without any blockages or obstructions.
Unused/surplus cables, steel items and steel scrap
lying scattered at different places within the working
areas shall be removed to identify locations(s).
Don't through any grinding wheels on open site once
used. It must be properly collected & disposed through
authorize vendor or as specified by manufacturers
guidelines
06 De-stressing of LWR track by FBW cum de-stressing
machine and super puller
Destressing shall be carried as per approved procedure.
Only Trained and experienced person shall be engaged
for work.
This work shall be carried out in presence of site
engineer.
Unauthorized person shall not be allowed near the job.
While doing supper pulling job the clamping of rail shall
be ensured.
Site Engineer
/Supervisor
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14. Sensitivity: LNT Construction Internal Use
All equipment shall be checked by P&M prior to using at
site.
All required PPE shall be used by workmen.
The molten slag of Flash butt welding shall be
immediately quenched or covered
All the Railway safety rule shall be followed while doing
the job.
Residual Risk / Impact (if any):- Low (ALARP)
8APPENDIXES
APPENDIX 1– Proforma for details pertaining to destressing.
APPENDIX 2– Hazard Identification and Risk Analysis (HIRA)
APPENDIX 3– Operating & Maintenance Manual of 160T Super Puller
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