TTPS Operation Circle MPM II Unit Overhauling of mill, gear box, under bowl, mill outlets, classifier assembly etc in Mills 5A, 5B and 5C during 2021 annual overhaul

Charges for draining the oil from mill gear box, cleaning the gear box, worm wheel, worm shaft with neat cloth, arresting of oil leaks and refilling the gear box with old or new oil as directed by the Engineer–in charge, including transportation of material from and to stores and cost of consumables.

Charges for Dismantling of upper skirt assembly, lower skirt assembly, Mechanical face seal assembly, dust guard and blue matching of seal runner, renewal of seal (bronze), air seal, dismantling of Mill bottom cover, upper bearing housing cover, oil seals etc., Complete overhauling, assembling back the lower skirt assembly, scrapper assembly and arresting the oil leakages in the return line and also spillage’s at the rear side of gearbox to prevent Mill fire including cleaning and tapping the threaded holes.

Charges for dismantling the gear coupling bolts, gear coupling (worm shaft only), distance piece, unscrewing the worm shaft extension cover bolts and bearing housing cover bolts, removing the worm shaft extension cover, lowering to ground floor, releasing the worm shaft assembly from its position and assemblies providing back the overhauled worm shaft assembly in the gear box and fitting back the worm shaft extension cover, bolting and tightening the bolts to the required torque level and assembling back the gear coupling bolts, distance piece etc.

Charges for checking the bearing clearance after dismantling the thrust bearing and radial bearing housing covers, removing the bushes, springs etc. thoroughly cleaning the bearing housings and other components inspecting the thrust bearings, resetting the axial clearance by reducing the thickness of shims in the thrust bearing housing cover, providing of new shims and by trial method adjusting the clearance to 0.10 mm to 0.15 mm. Assembling back the thrust and radial bearing housing properly and renewing the gland studs and gland packing in the worm shaft assembly.

Charges for changing the worm shaft thrust bearing after gas heating and releasing the old bearings from the worm shaft, heating the new bearing in oil bath and providing the new bearing in the worm shaft in proper position.

Charges for renewing radial bearing in the worm shaft after gas heating and releasing the old bearing and providing new bearing in the worm shaft after heating the bearing in oil bath.

Charges for dismantling the wornout spool pipe and MPO (each 4 Nos.) after supporting the relevant coal pipes firmly and disconnecting the victaulic coupling, air line and other accessories and replacing of liner, old /new victaulic coupling gaskets, replacement or inverting the orifice and re-fixing MPO, MDV or spool pipes as per the direction of Engineer in charge. The work includes lead, lift of materials from `0’ meter and devolution of scraps to stores and cost of consumables such as cutting gas, welding electrodes etc.,

Charges for dismantling and lowering of wornout vertical discharge coal pipe, changing the eroded pipe portion, collars etc., or replacement of pipe with new/ old distance piece if required and lifting and re-aligning the vertical pipe in the mill as directed by the Engineer incharge. This includes lead, lift consumables such as cutting gas, M.S. Welding electrode etc.

DURAI ENGINEERING WORKS