repairing and full overhauling of sdl parts (a) 04 nos. of gearboxes and (b) 06 nos. of idler-1 04 nos. of gear box 1.01 gear box sprocket opened and dismantling by gas heating both side. 1.02 gear box floating ring and seal kit new replacement. (eea0015809) 1.03 h.t. bolt new replacement and fitting 24mm x 75mm. 1.04 gear box overhauling and opening fitting. 1.05 h.t. bolt new replacment and fitting 12mm x 30mm 2 06 nos. of idlers 2.01 track chain idler assy dismantling full overhauling repairing and assembling 2.02 repairing of worn out portion of idler bracket seat collar by welding and machining as per original dimension for proper assembly 2.03 repairing of worn out bearing seat and colour of idler shaft by welding machining 2.04 damaged and wornout bearing cover seat repairing by welding metal filling and machining as per bearing seat and dust seal 2.05 broken and seized bolt removing by drilling from idler collar 2.06 new thread making in idler collar 2.07 providing and fixing of ht bolts 12 mm x 30 mm 2.08 providing and fitting of bearing 4t-623/612 2.09 providing and fixing of idler seal kit