“It is big yellow coloured machine, for which you have to arrange blocks, arrange diesel and output is monitored by HQ”
“Track machines are an essential part of Track Engineers life. You cannot be
without them. So know them, care for them, and you will start loving them”
Need for Track Machines
• Modern Track cannot be laid and maintained manually.
• Mechanized maintenance of track was introduced in early sixties.
• Track machines are of two categories.
– ON TRACK machines
– SMALL TRACK machines.
• For ON TRACK machines, track machine manual was first published in march 2000.
• Small Track machines (STM) manual was first published in july 2005.
ON TRACK Machines
ON TRACK Machines
First modern machine,Bogie type machine,More leverage on 13 m base , less stress on rails/machines,A work site machine,Sending CSM is not ideal atworksite,Tamping of 2 sl / insertion,1600 sl/ hr ( 450 for UT and 700 for Unomatic), Stopping - Packing – Moving ahead –Stopping
Continuous Action Tamping Machine (CSM 09-32)
Basic work horse for maintenance, 300 machines world over 2000-2400 sl / hr, Satellite unit with tamping and levelling / linig unit Machine continuously moving, Satellite unit moves stops packs and moves Only 20% mass stops and moves, Less stress on operator, Microprocessor control
Tamping Express 09-3X
2700 sl / hr, 2 temping units each with 1 ½ sleeper packing 3 sleepers at a time, Total 48 tamping tines, Original tools are carbide tip tools --- 600 km , Computer on board with lining levelling programme measuring run to record track parameters.
UNIMAT 08-275
Points and crossing tamping machine, Tilting / swirling tools 3rd rail lifting arrangement in (3S) machines, Manual lifting of 3rd rail in 2S machines, 1 t/out per 90 minutes
Ballast Cleaning Machine (BCM) - RM-76
Plasseuer make machines RM-80 for plain track and RM-76 for points and crossings, 550 Cum / hr , Extendable chain for turnouts extendable by 450 mm per unit
Ballast Cleaning Machine (BCM) - RM-80
Replacement of overhauling, Only shoulder not crib, Cutter chain on sides KSBC KERSHAW 3-4 machines have wheel cutter, FRM-80 Plasser make 550 cum/hr
T-28
Moves both on rails and crawlers on plain surface, A pair of machines work together, Special trolleys to carry assembly AMECA Italy make
DTS (DGS-62-N)
Controlled vibrators, Agitate entitle track frame, Controlling entire track Geometry during vibrations,High retentivity of packing,Very useful in tamping in summer-no buckling, D/S site can be used for early relaxation
RAILVAC Jumbo VM-170
Vacuum cleaning machine, Cleans up fouled ballast, 200mm hose,Cleaning of side drains, tunnels , Two vacuum chambers , Material unloaded into a wagon attached, Total muck holding can be 35 cum,Cost around 10 cr.
PQRS
Pre-Tamping Attentions
• The PWI should carry out field survey on foot to determine the existing profile of track, ballast deficiency and general lift.
• Ballast deficiency found if any should be meet out. The ballast should be heaped up in tamping zone. The rounded ballast near the joint should be removed
• Low joints, hogged, battered and cracked joint should be attended first.
• Location of pumping should be identified cleaned and screened.
• Low cess level should be made up so that ballast may retain to profile.
• Any missing fittings should be recouped and fitting existing should be tight.
• Broken / damaged sleepers rails fitting and fastenings should be replaced.
• The spacing and squaring of sleepers should be done before tamping so that the tools may not damage the sleeper.
• The beginning and end of curve, transition curve and the amount of slew should be marked on sleepers.
• If necessary the creep and gap adjustments should also be don’t in advance.
• If curve has been distorted badly the realignment should be done and amount of superelevation and versine should be marked on the sleepers.
• In LWR, if required the Destressing should also be done before machine tamping.
• The check rails at level crossings, curves, the guard rails at bridges should be removes before tamping.
• At level crossing the road should be opened and overhauled if dues should also be done.
• If alignment of track is severely disturbed it should be attended.
• The wooden blocks, joggled fish plates, glued joint bonds, earthing bond should be removed before tamping operation.
• S&T wires, electric cables, pipe lines, signal rods, lubricators if provided and any other obstructions should be removed in presence of authorized representative of concerned department.
• Lifting if required more than general lift should be carried out in advance.
• The end of sleepers should not be covered with ballast during heaping operation.
• The distance of fixed structure from centre of track and its height from rail level should be recorded so that infringement if any may be determined.
• If lifting is required more than 15mm the reference pegs should be fixed and gradient should also be marked.
• The track parameters such as gauge, cross level, alignment etc should be recorded before tamping.
During Tamping Attention
• The machine should have full number of tamping tools not shorter than 10% in any circumstances. The wear of tools should not be more than 20% of its cross-sectional area.
• The vertical gap between bottom edge of sleeper and top edge of tamping
• The squeezing pressure of tamping tools should be as follow:-
a) In Plain Track
• The Insertion of tools should be as follows
a) Metal Sleeper- 2 insertions before passing to next sleeper.
b) Concrete Sleeper- 1 insertion upto 30mm lift and 2 insertion for more than 30mm lift.
c) Wooden Sleepers- 1 insertion upto 20mm lift and 2 insertion for more than 20mm lift.
d) The joint sleepers should be packed by one additional insertion. Care should be taken the tools are inserted centrally to avoid damage to sleeper.
• The squeezing time should be 0.4-0.6 seconds. It can be set in multiple of 0.2 seconds in Tie Tamper Selector Switch in the working cabin. The setting of 1-2-3 will mean squeezing time 0.2-0.4-0.6 respectively.
• The lifting or slewing should be done 50mm at a time in PSC sleeper and 25mm at a time in other sleepers.
• A ramp of 1 in 1000 should be given before closing the work. This ramp should also be ensured at starting also.
• If tamping work is to be done in night hours the sufficient lighting arrangement should be made.
• If there are metal sleepers the fitting should be checked during tamping.
• During tamping work the track parameter should be checked and corrective action if necessary should be taken immediately.
Post Tamping Attention
• The broken/damaged sleepers, fittings and fastening during tamping should be replaced after tamping operation.
• The fittings and fastenings which have loosened should be tightened.
• The ballast should be boxed and dressed in profile and proper compaction should be done.
• The track parameter achieved finally should be checked by recorder provided in tamping machine. If recorder is not provided in tamping machine the parameter of at least 4 stretches of 25 sleepers each in a kilometer should be measured manually.
• The final track parameter should be as follows:-
• The gap/void left in tamping zone should be recouped manually.
• The check rails at level crossings, curves should be re-fixed. If it is not possible to fix the check rail immediately a speed restriction of 30kmph should be imposed but, check rails should be fixed within 24 hours positively.
• The pipes, cables, S&T wires, bond wires, signal rods, joggle fish plate, wooden blocks should be re-fixed in proper position.
• The infringement should be checked after tamping work.
Operation of Tamping Machine in Design Mode
1. Selection of Datum rail:
The datum rail for carrying out of attentions to longitudinal profiling and alignment should be selected as given below:
a. Longitudinal section: Non-cess rail on straight track in double line section and
inner rail in curves.
b. For alignment: non-cess rail on straight track in double line section and outer rail on curves.
c. For single and middle line in multiple line sections, any of the two rails which
is less disturbed may be selected as datum rail, both for alignment and L-section
in straight track.
2.Survey for vertical profile correction:
The section identified for surfacing should be divided by stations marked at 10 m interval. The starting point should be opposite a km post and the starting station should be marked 0. Station locations and station numbers should be painted in yellow paint on the web of the datum rail.
Bench marks:Bench marks should be established at 200-1000 m interval, relating them to the GTS bench mark levels so that the plotted drawings are properly related to the existing index section. Fixing bench marks in relation to arbitrary levels should be avoided. These bench marks should be avoided. These bench marks could be established on the top of concrete foundation of OHE masts on electrified sections.
Recording of Actual Rail levels:The SE/JE (P. Way) should record the actual rail levels at all the stations of the datum rail, making use of the established bench marks. However, on the stretches where the datum rail is super-elevated, being on a horizontal curve, the rail levels should be taken on the other rail of the track opposite the station locations. The stretch for which station levels are taken on "non- datum" rail, should be noted in the level book.
In view of the voluminous survey work involved, auto setting levelling instruments should be used to reduce man-power to save time and to achieve accurate results.
Hard formation levels:At every 5th station i.e. Station No. 0, 5, 10 etc., the Section Engineer/P. way should remove ballast below the rail seat where rail levels are recorded, upto a level, below which it is not desirable to go, while carrying out deep screening work. This level is referred to as Formation Level. The SE/JE (P. Way) should also record the formation levels. For example, in the redesigned vertical profile the rail level should be 700 mm and 680 mm above the formation level in case of 60 kg and 52 kg rail respectively on PSC sleepers with 300 mm ballast cushion, if sub-ballast is not provided.
Obligatory Points:While carrying out the survey, the SE/JE (P. Way) should record the location of obligatory points like level crossings, girder bridges, points and crossings, overhead structures etc., in reference to the station numbers as well as running kilometre. In addition, the location of km posts and gradient posts should also be noted.
3.Plotting of vertical Profile:
The existing vertical rail profile (of datum rail) and formation profile should be plotted on a graph sheet with the length of track as abscissa and elevation of rail top and formation as ordinate. The scale adopted should be:
Horizontal Scale: 1:1000 or 1 cm = 10 m and
Vertical Scale: 1:10 1 mm = 10 mm
Having plotted the formation levels the desired rail levels should be marked on the graph e.g. by adding 70 cm to the formation level, in case of 60 kg track on PSC sleepers with 30 cm ballast cushion and 68 cm in case of 52 kg track on PSC sleepers. The desired rail level so plotted should be taken into account, while marking the proposed vertical profile on the graph.
4.Proposed rail Profile:
While deciding the final levels, the following considerations shall be taken into account:
i) Sub sections shall be selected keeping in view high points and obligatory points.
ii) As far as possible, long stretches of uniform gradient shall be planned keeping in view the depth of construction to be provided, and relative implications of lifting or lowering of track. In no case the grade should exceed the ruling gradient of the section. While designing vertical curves, provisions should be observed.
iii) The clearance to overhead structures (including OHE ) shall be maintained within permissible limits.
iv) The redesigned profile should not normally involve lifting or lowering of obligatory points like girder bridges, Level crossing and turnouts.
v) The redesigned profile should aim at easing the sags and humps with manageable lift and lowering. It is not necessarily the intention that the original longitudinal section of the line should be restored.
vi) Generally, the redesigned profile should be so arrived at as to have lifting only, as machines have lifting facility only, and lowering shall be resorted to in exceptional circumstance.
vii) Prescribed minimum ballast cushion should be ensured. However the requirement of ballast over and above that for the prescribed cushion can be optimised by designing suitable vertical curves.
viii) At locations where lifting or lowering is not possible, suitable ramping out preferably in the form of reverse curves in vertical plane should be provided on both approaches. In case lift is proposed at level crossings, the field staff should be prepared to simultaneously raise the road surface and regrade the approaches
5.In redesigning the profile, the requirements to be met are:
i) For other than vertical curves-
The unevenness on 20 m chord should not exceed as under:
a) on high speed routes with speed above 110 kmph - 40mm (corresponding to 20000m vertical radius).
b) on other lines - 65 mm (corresponding to about 12000 m vertical radius).
ii) for vertical curves - The unevenness on 20 m chord should not exceed 10 mm
(corresponding to 5000 m vertical radius)
The profile designed should be analytically verified so that the above mentioned unevenness limits are not exceeded. The final levels at various points should be calculated rather than scaling out from the drawing which mainly serves the purpose of visual appreciation..
The proposed levels should be approved by an officer not below the rank of DEN.
The working plan so prepared should be distributed to the concerned field staff and AEN.
Designing Vertical Profile With the help of Computer For designing of vertical profile, aid of a computer with a software developed by IRICEN/Pune may be taken to speed up the design work.
6.Surfacing Operation
The filially proposed levels of rail top may be marked on the OHE masts for executing the lifting/lowering operation. In case of non-electrified section, permanent level pegs should be provided at every 5th station. Actual work of lifting and lowering may be carried out in keeping with the instructions laid down.
The finished profile may not exactly conform to the redesigned profile, and the resurfaced levels may vary from the design profile. It is, therefore, necessary to check the finished levels in relation to the levels marked on the OHE posts or other reference points. The difference between the finished levels and designed levels should not exceed 10 mm, provided the variation of unevenness from station to station is not more than 20 mm. To ensure this, SE/JE (P. Way) will workout the unevenness at all stations in relation to the finished levels and the machine incharge shall apply correction to levels, to bring the station to station variation of unevenness within the prescribed limit
7.Survey For Alignment Correction:
All the weld and rail kinks should be rectified/eliminated by dekinking or cutting
and welding, before measurement for alignment defects are taken. Hydraulic jim crows may be used for removing kinks. In case some horizontal curves on the section to be surfaced warrant realignment, then the process of realignment should be carried out along with surfacing. Alignment should be measured on a 40 m chord on straight track and required slew at alternate sleeper should be worked by measuring the offsets at every 5 m interval and interpolating the offsets. The slews are marked on every alternate sleeper. On curved track, versines should be measured on 20 m chord at 10m intervals. The required slews at the stations are worked out taking note of the obligatory points and interpolated to give slews at every alternate sleeper. The slews are then marked on alternate sleepers. While working out slews, position of fixed structures should be noted and infringement to moving dimensions shall not be allowed. Pre-tamping and Post Tamping operation and machine related track works as detailed shall be ensured by the Section Engineer P. Way)
Single Chord Lining System:-
This system is provided on all the tamping machines except UT machines and is controlled electronically. The system has
This system is provided on all the tamping machines except UT machines and is controlled electronically. The system has
arrangement both for 4- point and 3-point lining.
i) 4- Point Lining Method Trollies at A, B, C and D are pneumatically pressed against the rail selected for line measurement, usually the high rail of a curve. The wire chord stretched between A and D represents the 'Reference Line' and the transmitting potentiometer (Transducer) which are fixed to the measuring trolley B and lining trolley C are connected to this wire by means of Forks and the wire drives.The measured ordinate at B is multiplied through the electronic circuit by the specified ratio and compared with ordinate at C. Then electronic signal is emitted which activates the hydraulic control of the lining mechanism to effect necessary correction.When working on transition portion of curve, necessary adjustment can be applied by digital control on the front trolley. The method of applying adjustments is explained
ii) 3-Point Lining Method
The track is measured at three points B, C and D and lined according to specified
theoretical versines. The chord at measuring position B is fixed by the Fork and the potentiometer is switched off. The ordinate at C only is measured on chord BD and compared with preset ordinate value. Any difference detected will activate tile lining control to effect the necessary correction
The 3-point method is mainly used if:
- The track is to be lined according to specified radii or versines
- The lining system is used in conjunction with a sighting device and remote control
or a Laser.
-Failure Of Track Machines In Mid-section
In the event of break-down, the track machines shall be protected (By placing first detonator at 600meter from machine and three detonators at 1200m at 10m apart from the place where machine has failed.) and SR thereto by the machine staff, as directed by machine incharge.
Failures in block sections of the track machines will be treated as accident under
class 'H'. Accidents involving track machines shall be treated as train accidents under the appropriate class and action shall be taken as per the rules in force.
In case of failure of track machine in block section, the Junior Engineer/Section
Engineer (P. Way) may decide to push the disabled unit to the nearest station provided the brake power is in good condition. Otherwise, intimation shall be sent to the nearest Station Master through a messenger and to the Control through portable telephone asking for a light engine to tow the unit.
In case, machine incharge feels clearance of section is going to take long time, the assistance of Accident Relief Train shall be asked for immediately. Meanwhile the machine incharge shall take necessary action to rectify the defect(s).
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