Page 108 - GM E-booklet 2022-23

4.6. MABD FOB (FULL FOB LAUNCHING IN 90 MIN BLOCK ONLY)
The bed plates are prefixed and welded to girders taking exact site
measurements from centre of girders to respective columns centres on
either sides of platform separately and accordingly holes are drilled in
cap plate and bed plates instead of pre assumption of all columns on
either sides of the platform are equidistant.By doing so all field mistakes
during errection of main columns have taken in to consideration by
actually measuring and plumbing at site. So by doing above nearly 10 to
15 minutes have been saved for matching of bed plates and cap plate
centres and doing welding and redrilling or relocating of earlier drilled
holes for each girder during block.And with the above technique the
holes for top bracings and cross frames are altered as per site conditions
for each girder instead of adopting same distances for all girders.With all
above minute planning have saved for 3 girders launching 3x15-45
minutes or else it could have been required 2hours 30minutes block, but
work has been done 90mintues all 3 girders launching by saving precious
45minutes block of both UP and DN lines.

Launching of girders in process at MABD FOB

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