Repair and Rehabilitation of Hydromechanical equipments like regulator hoists, starter boxes hoist chain and chain sprocket damaged counterweight corroded chequered plates damaged screw rod in RMC electrification of RMC LMC vents and surface coati

Providing Z type rubber seal on either ends of the shutter with SS side seal seat as per the following specification. The seal seat shall be made of MS flat 70x16mm of length 1830mm and seal cover flat shall be made of MS flats 55x10mm of length 1830mm. They are tag welded together for matching and M10 holes shall be drilled with a centre to centre distance of 100mm. The seal seat shall be tap drilled size of M12. The seal cover flat shall be drilled M14 over the pilot drill. The seal seat shall be fitted with skin plate both ends and welded with skin plate. Now the ‘Z’ type seal of size 74x79x16mm shall be cut to the required size and matched with the seal seat cover and holes are punched in the rubber seal accordingly. Now the Z type seal shall be sandwitched between the skin plate & seal seat cover. SS bolts M12 shall be used to fasten them to the skin plate. SS flat of size 70x8m and of length 7700mm is used as side seal seat. The flat shall be cut to a length of 2000mm and fixed appropriately in the groove angle to act as side seal flat to reduce the friction during the sliding of rubber seal at the side. The cost includes cost all of materials, labour charges, transport, erection, hire charges for machinery, incidental charges like conveyance to & fro from site etc., complete and as directed by departmental officers.

Repairs and Replacement of bottom rubber seal of the spillway shutter as per the following specification. The old rubber seal shall be removed from the skin plate after removal of the rusted bolts & nuts by gas cutting equipments. The seal seat cover shall be removed along with the rubber seal. The skin plate & seal seat cover surface shall be neatly cleaned on either side by grinding. Now, the existing seal seat cover made of 100x10mm MS flat & the new rubber seal shall be now matched with the existing holes in the skin plate and then holes shall be drilled in the seal seat cover to align with that in the skin plate, if necessary. 18mm holes shall be punched accordingly in the rubber seal of size 100x12mm. The inside surface of the seal seat cover is given a coat of anticorrosive zinc rich primer over which two coats of coal tar epoxy shall be applied at an interval of 24 hours between each coat. Now the rubber seal shall be placed on the skin plate over which the seal seat cover shall be placed and fastened with SS bolts & nuts of size M16x75. The cost includes cost all of materials, labour charges, transport, erection, hire charges for machinery, incidental charges like conveyance to & fro from site, etc., complete and as directed by departmental officers.

Repair, overhaul & refixing of the rusted cast iron wheels of the existing shutters with gas cutting equipment and reconditioning with bushes / bearings and refixing to the original condition as per the site requirements. The wheel is of 200mm diameter & moves in the recessed groove of the vertical guide channel. The shutter shall be lifted to a workable height and the locking plate shall be removed by cutting the corroded bolts & nut with gas cutting equipments. The wheel pin shall also be removed. Then the wheel shall be transported to the workshop where the wheel shall be opened up and the old broken bearing & bushes shall be removed after cleaning the wheel. Then the outer wheel surface shall be machined true to required size and so that it shall operate smoothly without vibration and without undergoing undue drift. The inside of the wheel shall also be machined to have a uniform surface. The existing bearing shall be cleaned and inspected for misalignment and breakage. Then shall be replaced as the case may be. The existing pin shall be machined and fitted snugly. Then the wheel shall be closed and fitted to the end vertical channel. Trial operation shall be conducted to ensure free movement & rotation of wheels. The cost includes cost of all materials, process charges like gas cutting, welding, machining, scaffolding charges, labour charges for dismantling, loading, lifting, unloading, transport, erection, labour charges for equipments like crane, chain pulley block, power charges for generator, risk allowance for working at a height of more than 3m, conveyance to site and clearing them after completion of work including cost of trial operation etc., complete and as directed by the departmental officers.

Overhauling of existing hoisting arrangements for the shutter as per the following specification. The existing hoist covers shall be opened up and stored separately. The top cover of plummer blocks connecting the existing transmission shafts shall be opened and old grease shall be removed. Then, the existing bearings shall be cleaned with liquid cleaner and inspected for mis-alignment and breakage. Fresh grease shall be applied to the plummer block and top cover closed with requisite fasteners. The shaft shall be checked for its alignment and redone to ensure straightness of shaft. The existing gear wheels shall be cleaned of dried grease and dust manually. The reduction gearbox shall now be drained of old used lubricant thro the drain hole at the bottom. Now, the liquid cleaner shall be poured in the gearbox and the inside surface and gears are thoroughly cleaned and then the contaminated liquid cleaner shall be drained. The drain hole shall be plugged and fresh lubricant of appropriate grade shall be filled to the level as indicated by the department officers. The available chain hoist in the hoisting system shall be manually cleaned of dried grease and dirt and appropriate lubricant shall be applied. The whole arrangements shall be tested & passed after a set of trial operation. The cost includes cost of inspection, spares, lubricants, transport charges, charges for dismantling & erection, etc, complete.

Replacement of existing chain link assembly in chain hoist as per the following specification. The either ends of the chain hoist shall be provided with new chain link. The roller chain for balancing shutter & counter weight assembly shall be made with low/medium carbon steel straps of 5 inch pitch. The minimum breaking strength of strap shall be 500 N/mm2. The straps shall be connected with medium carbon heat treated steel pins. The breaking strength of pin shall be 600 N/mm2. The new chain assembly shall suit existing chain sprocket. The upstream end of chain shall be fastened to shutter lifting assembly. The downstream end of chain shall be connected to counter weight lifting assembly. Necessary lubrication shall be applied to the chain link components. The cost includes cost of all materials, process charges like gas cutting, welding, machining, scaffolding charges, labour charges for dismantling, loading, lifting, unloading, transport, erection, labour charges for equipments like crane, chain pulley block, power charges from generator, risk allowance for working at a height of more than 3m, conveyance to site and clearing them after completion of work including cost of trial operation, warranty for 5 years etc., complete and as directed by the departmental officers.

Providing sprocket to suit rollers of dia 48mm as per the following specification. The sprocket shall be made of C45 material with 10 teeth and tip diameter of 450mm. The teeth profile should adhere to ISO 606. The pitch shall be 130mm. Heat treatment shall be done to a case depth of 1.00mm. The hardness shall be 30-40 HRC. The tolerance shall be followed as per IS 2102. The teeth profile edges shall be chamfered. A phosphor bronze bush shall be provided in the bore of 170mmØ The cost includes cost of materials, charges for casting, machining, milling, heat treatment, transport, erection, warranty for 5 years etc, complete as directed by the departmental officers.

Providing counter weight arrangements of the following size & specification. The steel box is of length 13000mm x 410mm x 310mm height. The bottom plate is made of IS 2062 MS plate 20mm. The sides are made IS 2062 MS plate 16mm. The top cover is made of IS 2062 MS plate 10mm. The joints are firmly welded to withstand rigorous work environment. The box is divided into 6 compartments with IS 2062 MS plate 16mm acting as stifferners. Concrete blocks of size 150x150x150mm is neatly stacked in these compartments. Locking plates of size 300x870 are welded in the inside of the box from the bottom, on both corners of the box. 40mm dia holes are drilled in the plates for locking of chain & locking of counterweight while carrying out repairs in the shutter. A Groove guideplate made of 20mm MS plate is welded to either sides of the box one at top & one at bottom. This plate serves as guides to the counterweight arrangement while moving up & down.Steel scaffolding is done upto a height of 5m to install the counterweight arrangements. Mobile crane is used to handle the box during installation of the counterweight arrangements. The hoist arrangements for the counterweight is dismantled and inspected for failed components. The main shaft of size 50mmØ, EN 8 rod is dismantled & replaced as it is distorted. The gear shaft of size 80mm dia is replaced ad it is twisted. Also, the plummer blocks at the end are replaced as they are broken. The hoist arrangements is reassembled with proper alignment & lubricants are applied, whereever necessary. The chain links broken are repaired & replaced whereever necessary. The cost includes cost of materials crane charges, scaffolding, labour charges, hire charges for machinery etc., complete.

Fabrication, supply and installation for centre hoist cover by using composite panels of thickness 3mm made as a single unit as per the drawing. The composite cover shall be spaced in such a way to resist bending with inherent stiffeners provided. A lifting handle in steel/composite material shall also be incorporated. UV resistant polyester polymer and high grade reinforcement shall be used for fabricating composite rope drum enclosure. The composite material made of glass fibre reinforced polymer shall be of high strength to weight ratio, durable, ease in handling and with better anticorrosive properties. The cost includes cost of mould, pattern and fixtures, cost of raw material like UV stabilized polymers, multi directional glass fiber reinforcements, hardeners, UV stabilized pigment & fumed silica powders, cost of consumables like rollers, brushes, gloves, sanding sheet, acetone, buffing, grinding & cutting wheels, cost of tools like aluminium paddle rollers, squeegees, fibreglass scissors, measuring beakers, agitators, cost of release agent like, cleaner, sealer, releaser, wax, labour charges for pattern & mould work, hand layup, cutting, grinding, finishing, drilling, loading, unloading, transport, erection, hire charges for equipments like air compressors, pneumatic tools, gelcoat spray gun, conveyance to site and clearing them after completion of work, including cost of trial operation, etc., complete as directed by the departmental officers.

Fabrication, supply and installation of hand operating chain for Hoisting arrangements by using composite panels of thickness 2.5mm made as a single unit as per the drawing. A lifting handle in composite material shall also be incorporated. All surfaces shall be applied with two coats of anticorrosive and UV resistant grade polymer coating. The composite material shall be of high strength to weight ratio, durable, ease in handling and with better anticorrosive properties. The cost include cost of materials, labour charges for fabrication, painting, loading & unloading, transport, etc., complete.

Replacement of old damaged starter box for the following specification. The starter to motor old cable shall be replaced with 4 core x 6 sqmm copper flexible unarmoured cable for cable leading from starter to motor. Necessary gland & lugs shall be used as required. Starter to motor cable shall be protected with 1” Ms pipe. A new DOL starter with forward & reverse shall be provided inside the old panel box after removing the old existing damaged starter. The starter box enclosure made of hybrid composite super structure panels. This process ensures freedom from all defects and this increases the strength of the composite box. UV resistant polyester polymer, fire retardant and high grade reinforcement shall be used for manufacture of composite enclosures. Excellent corrosion resistant gel coat shall be applied during the process. The composite material has high strength to weight ratio, durable, excellent corrosion resistant and very good insulator. The starter shall be housed in 20A contactor – 2nos, 12 to 18 amps relay – 2nos, single phase preventer – 1 no, pushbutton for forward, reverse & off, indicators lamps -3 nos, 32A 4 pole MCB -1 no & terminal -1 no shall be welded after removing the existing cover. The cost includes cost of composite enclosure box & accessories cable from starter to motor, labour charges, painting , transport charges, erection at site etc., complete..