INSPECTION AND MAINTENANCE OF SWITCHES AND CROSSINGS

Maintenance (General)

1. In big yards regular cycle of maintenance covering all points and crossing should be made.

2. Cess should be kept low for efficient drainage. Adequate ballast cushion should be provided.

3. Sleeper should be at correct spacing.

4. There should be no junction fish plates at stock rail joints or at the heel of crossings. At least one rail length on either side should be of the same section.

5. Use of spherical washers at appropriates places is very important and must be ensured.

6. At all places in point and crossings, the gauge should be uniform except at a point just ahead of the toe of a switch, where it will be slightly slack (enough to house the tip)

7. The clearance at the toe heel of switch, at check rail and wing rails must be maintained with in prescribed tolerances.

8. Adequate creep anchors should be provided to arrest creep. Box anchoring of at least one rail length ahead of stock rail is recommended. In case of PRC sleeper layout with elastic fastening creep anchors need not be provided.

9. It is desirable to weld stock and lead rail joints.

Maintenance of switches

1. In case of straight switches, correct bend to stock rail at the theoretical toe of switch should be ensured.

2. Bent Tongue rail should be straightened. Badly worn and damage stock and tongue rails should be replaced by serviceable ones. A tongue rail may be classified worn or damage when;

(a) It is chipped or cracked over a length of 20cm within 1 metre from its toe.

(b) It does not house properly against stock rail causing a gap of more than 5mm at the toe.

(c) The wear on tongue rail should not exceed the following limits :

(i) Vertical wear : 8mm for 60 kg, 5mm for 52kg and 90 R.

(ii) Lateral wear to be measured 13 to 15mm below the rail table 8mm for 60kg, 6mm for 52kg and 90R rail and 5mm for 75R and 60R rail.

3. Tongue rail should bear evenly on all slide chairs. This will be ensured when all sleepers are well packed.

4. When the tongue rail is in closed position, it must bear evenly against distance studs and blocks.

5. All bolts on switches should be kept tight except those at the heel of loose heel type switches where the first two bolts in the tongue rail should be finger tight and the other two in the lead rail spanner tight. On such switches a bend is given to the fish plate at loose heel joint equal to throw of switch x half length of fish plate/length of tongue rail.

6. Wear on switches can be reduced by lubrication of the gauge face of the tongue rail.

7. Plate screws and fang bolt should be used with slide chairs and not round spikes.

8. On prc T/O, rail screws provided on slide/spl chairs shall be lubricated to prevent from being jammed.

9. For better life of the rails in T/O, lubrication of gauge face on outer rail in T/O side shall also be lubricated along with tongue rails.

Maintenance of Crossing

1. Proper maintenance of gauge at crossing is very important. Any damage to nose of crossing or excessive lateral wear to the wings or check rails may have its origin in poorly maintained gauge.

2. Maximum vertical wear on wing rail at nose of crossing should not exceed 10mm. Crossing should be reconditioned replaced before reaching this limit.

3. When steel trough sleeper are used in crossing, the use of wooden blocks under them help in better maintenance.

4. For CMS crossings, gapeless joints must be en ensured for better running and preventing possibility of rail end fracture.

Maintenance of lead Portion and Turn in Curves

1. The curve lead should be laid by offsets from the gauge face of the straight track or by versine measurement. In later case stations at 1.5 m intervals should be marked and the versine checked on 6.0 metre chord. If there is variation in versine, track is to be attended. 

The turn in curve should also be checked for condition of sleepers and fastenings.

Schedule of inspections of points and crossings:

(a) JE/SSE’s inspection :SSE in-charge and his JE/SSE should carry out inspection of points and crossing in passenger running lines once in three months and other lines once in six months by rotation.

(b) AEN’s inspection : The AEN should inspect points and crossing on passenger lines once a year and 10 percent of other points and crossing every year.

(c) DEN’s inspection : A few points and crossings in running lines, at his discretion, particularly those recommended for renewals.

(d) All inspection should be done as per the proforma laid down for this purpose.

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