West Central Railway Office
of the
General
Manager
Engineering
Branch
No. No. WCR-HQ/W/601/Track/21/II Dated:-
Sr.DEN(
Sub:- Winter Precautions.
****
The winter is fast approaching. Incidences of rail fracture and weld failure
show a rising trend in winter, specially at the start
of winter. Track requires extra
attention specially during this period. In order to prevent/reduce the fractures,
detailed instructions already exist on the divisions. These should be reiterated to all field
officials for information /compliance.
In addition following action may be
taken during winter.
1) Analysis of rail fractures and weld failures should be
done on your divisions to identify the block section which are fracture prone
and to identify the reasons for fracture so as to take preventive action as
deemed fit.MS Access programme
is already available with you for analysing Rail/Weld
failures.
2) Roster hours of key men should be changed so that
failures, if any can be detected in time.
3) Remedial measures indicated below in para (4) may be adopted in addition to other methods.
4)
Testing of rails by Ultrasonic Flaw Detector :-
I.
Frequency- As
per USFD manual, frequency of USFD examination may be decided, keeping fracture
proneness in view. A,B,C, & D routes are to be
essentially covered under need based system.
II.
Quality of USFD examination- Each fracture should be analyzed and effectiveness of
USFD examination be judged. If required,
USFD operators JE/SE/USFD
should be given necessary training. Fish
plated joints should invariably be scanned by single rail tester because the
double rail testers are not able to detect star cracks through fish plate hole.
III.
Intensification of USFD examination- Ultrasonic testing of track can be effectively utilized to control
rail/weld fractures. Salient provisions
of USFD manual are reiterated below:-
(a)
|
GMT |
Upto 8 |
> 8 < 12 |
> 12 < 16 |
> 16 < 24 |
> 24 < 40 |
> 40 |
|
Frequency ( Months) |
12 |
9 |
6 |
4 |
3 |
2 |
(b)
SKV
Welds – Initial acceptance test,
first testing after 80 GMT, subsequent testing, if weld failure due to flange
defect exceed 1% in a year in a block section.
A round of testing be carried be out after 8 years or 1% gross failure
in a block section since the second test.
(IV) Conventional AT Welds – Initial acceptance test, first testing after 80 GMT, subsequent
tests after passage of 40 GMT.
USFD testing of rails up to 16 GMT per annum should be
so regulated that one round of testing is done before the onset of winter i.e.
before 31st October.
Adequate monitoring should be done at divisional and
zonal railway to ensure that that flange testing of welds is carried out as per
the stipulated frequency. Records for at
least five years of testing should be kept for this purpose. Instructions already exists to test all AT
welds on important and major bridges and their approaches (
100m) once a year. This should be completed before onset of winter.
5.
Visual examination of Rail ends:-
Visual examination of Rail ends should be done to
detect any cracks emanating from bolt holes.
Visual examination of rails on
girder bridges, specially to examine corrosion in the
rail foot, should be completed before 31st October.
i.
Frequency of
Visual Examination of Rail Ends may be stepped up to detect any cracks emanating
from bolt holes.
ii.
Support AT welds
by wooden block and provide joggled fish plate with clamp at all AT welds more
than ten years old.
iii.
Carry out end
cropping and welding giving due consideration to remaining life of rail so that
battered ends are removed.
iv.
Carry out through
weld renewal wherever sanctioned.
v.
Where incidence
of weld fractures is high.
vi.
Carry out shallow
screening of pumping joints.
vii.
Carry out chamfering
of fish bolt holes.
viii.
Rectify joint sleeper
spacing wherever required including that of bridge timbers.
ix.
Gap survey should
be done in SWR territory and gap adjustments should be done where single rails
are there.
x.
SEJ inspection
and observation of creep of LWRs.
xi.
The rails are
known to corrode underneath the liners. Special
watch is to be kept for such rails as fractures are known to initiate from
underneath the location of liner. Visual
examination should also be carried out for the same.
6. Ensuring that all fittings are
available and are maintained in tight condition at joints. Provision of shims wherever fishing planes
have worn-out. Improvement in quality of welding in situ, Correction of joints
sleeper spacing, inspections and adjustment of gap at joints, Ensuring
distressing of LWR/CWR wherever incidence of fractures are higher or movement
of SEJ’s is erratic or beyond permission limits.
7.
AT welds more than 10 years old
Provide joggled fish plate with two far end
bolts/clamp on all conventional AT Welds.
Joggled fish plates with two far end bolts/clamps
should also be provided on all SKV welds more than 10 years old. This should be done in next 2 years time and thereafter
as and when due, on 10 years age consideration.
Immediate action should be taken to ensure the above
remedial measures for controlling rail/weld failures. A monthly review should be sent every 1st
day of the month in the already circulated MS ACCEES PROGRMME. Accordingly
Patrol chart of the gang unit wise are to be prepared for winter patrolling. Winters
patrolling of the sections are to be monitored at all levels.
Please acknowledge the receipt of this letter at all
level.
(Sonvir Singh)
CTE/WCR/JBP