| Structurals Features : |
| Bridge girder and end carriages : |
Shall be fabricated out of steel plates welded together to form a box. In addition to the required full length, short length diaphragms shall be inserted whenever required to transmit the trolley load to the web plates and to limit the maximum stress in the trolley rains within the safe permissible limits. All diaphragms shall bear against top flage. |
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| Trolley Frame : |
The trolley frame shall be fabricated out of steel plates and made rigid by providing suitable diaphragms. The frame shall be totally covered an openings shall be provided wherever required. |
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| Wire Rope : |
The wire rope provided shall be of 6 x 36 / 6 x 37 construction, best plough steels, STEEL core having a tensile strength of 160 / 180 kg/mm and shall be of parallel right hand ordinary lay as per IS : 2266 |
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| Wheels : |
The wheels of the trolley and the end carriages shall be forged out of EN 9 material, double flanged straight tread type fitted with anti friction bearings mounted on 'L' type bearings housing for the ease of maintenance. The wheels shall be hardened up to 320 BHN. |
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| Rope Drum : |
The rope drum shall be made from mild steel seamless pipe designed to withstand the compressive stresses by the wound of rope and the bending stress due to beam action of the drum and shall conform to IS : 3177. |
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| Gear Boxes : |
All gear boxes provided shall be totally enclosed splash lubricated type. The gear boxes casing shall be fabricated out of steel plates and duly stress relived. All Gears and pinions provided shall be of helical types only. Gears shall be machine cut out of EN 19 ( 245-280 BHN ) materials. The gears shall be designed in accordance with IS : 4460. |
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| Couplings : |
Special type of flexible geared coupling between the hoist and rope drum shall be provided.
Universal couplings shall be provided on the input side of the gear box. Geared couplings with floating shaft arrangement shall be provided for the cross traverse and long travel motions. |
Platform : M.S. Chequerd plate / anti skid platform shall be provided for full length on drive side of the bridge girder. |
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| Electrical Equipments : |
All motors provided shall be 6 starts / hours, 40% CDF slipring crane duty of reputed make.
Power supply to the trolley shall be through PVC flexible trailing cable fitting on cable trolley moving on a separate steel track.
AC operated electro hydraulic thruster brakes shall be provided.
Stainless steel formed grid type well ventilated Resistance box shall be provided.
Hoist motion shall be provided with rotary type limit switch to prevent the hook from over hoisting and lowering. Shunt lever type limit switch shall be provided on cross traverse and long traverse respectively. |
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