EOLB with Mechanical Boom locking

Hazard Identification & Mitigation

G.KUMARAN AMIRSE ADSTE/BPA.

MOLB with Mechanical Boom Locking.In MOLB,After closer of boom and

resting on to the meeting post gate man will operate the single way GF lever frame which locks boom through rod operation.

DemeritWith out closure of Gate

boom locking key from E-Type lock fixed on GF frame can be extracted when E-type lock worn out condition etc.,During this situation signal can be taken OFF in gate open condition.

EOLB with Solenoid Boom Locking

In EOLB, Once boom closes and

resting on meeting post the locking hook in the meeting post will be automatically locks the boom by counter weight arrangement

Proximity switch in the meeting post will be activated and gate close indication transmitted to panel automatically

EOLB with Solenoid Boom Locking RDSO/SPN/180/2005

Demerits Gate close indication

very frequently disturbed by in-disciplined road users during their passage.

Solenoid boom locking also getting failed frequently due to its fragile design.

CASE STUDY At PPZ Station LC Gate No.

52 EOLB boom lifted off from meeting post without disturbing the close indication. The angle of open was found around 5 degrees.

Angle of open 5 degree if convert into Meters is directly proportional to length of the boom, that means shorter length of the boom will have less opening than longer length of the boom, this can sometimes allow road vehicle to pass.

Failure Investigation Due to fast operation of

booms by gate man LC Gate close indication appeared and sticked through BLR relay front contact. This is as per circuit design. Stick contact incorporated in the circuit to avoid frequent gate close indication disturbance caused by road users. By this stick contact due to swinging action of boom in the meeting post proximity switch activated and gate close indication was permanently available though the boom was unlocked and lifted OFF from boom.

EOLB with Solenoid Boom Locking RDSO /SPN/180/2005

Solenoid Boom Locking hook was found permanently held unlocked position. The reason for this failure may be residual magnetism in the Solenoid Coil or may be mechanical stuck up. Residual Magnetism in the coil could not be ruled out because the armature was operating with higher current range.

EOLB with Mechanical Boom LockingRack & Pinion Lever to be installed adjacent to Gate man operating EOLB panel in the Gate Lodge for EOLB boom locking operation

Underneath of the gate lodge vertical crank to be fixed to convert the vertical motion into Horizontal motion of rod run.

EOLB with Mechanical Boom LockingExisting EOLB meeting post to be replaced with Mechanical meeting post duly fixing mechanical RDSO boom locking arrangement. After Boom resting on meeting post gateman will operate the Rack & Pinion Lever which will enable the locking of Booms.

After boom operation completed the key will be extracted from the lever and transmitted to Station through EKT,

HAZARD MITIGATIONBy providing Mechanical Boom locking on EOLB’s 1. Signal Restoring back to Red in the face of train

due to disturbance of gate close indication by road users eliminated.

2. Positive Boom locking achieved.3. Extraction of Boom locking key from lever

without closing gate intentionally or unintentionally signal cannot be lowered because in gate close indication circuit closer of boom (0-5 degree) in series with EKT contact proved.