Our company manufactured and carried out the installation of an electric bridge magnetic double-girder crane at one of the largest Ukrainian mining and processing plants. The main purpose of the new crane equipment is to unload the grinding bodies (so-called balls) from railway wagons with a magnetic washer, as well as to load them into containers, which are fed into a ball mill for fine grinding of ore before further enrichment.
During the negotiations, the Customer set the following tasks:
- Replace the existing bridge magnetic two-girder crane of 1959, retaining its basic technical characteristics.
- Change the position of the driver's cab, as close as possible to one of the end beams of the crane, and also rotate the cab by 90 ° to increase the viewing angle when unloading grinding bodies (balls) from the cars and their subsequent transportation;
- As close as possible to the complete set of the crane drive group (electric motors, gearboxes, brakes, gear couplings, drive wheels) to the bridge cranes already working at the plant. This requirement is due to strictly limited time for its maintenance in case of the need to replace / repair the crane components during the entire period of its operation (and this is more than 20 years).
- Include in the delivery set of spare parts for fast repair and operation of the crane in continuous mode for at least 3 years;
- Mount a new crane on the crane runway of an open trestle of a warehouse of balls in the current production conditions (without stopping the process of unloading / loading of grinding bodies with an existing crane).
To perform this task, a detailed technical task was prepared. During the manufacturing period of the crane at Kyiv Crane Machinery Plant LLC, the Customer carried out additional work to refine the existing trestle (taking into account the use of a new crane).
The main technical characteristics of the new crane:
- loading capacity - 5,0 t;
- crane span - 23.0 m;
- lifting height - 16.0 m;
- lifting speed - 23.0 m / min;
- trolley speed - 38.0 m / min;
- crane movement speed - 119.0 m / min;
- maximum power consumption - 47 kW;
- medium temperature operation - -30 ... + 50 ° C;
- climatic modification and category of placement - U1 (open air);
- degree of protection of electrical equipment and control equipment - IR-65;
- mode of operation - A7 (heavy).
The operating mode of the crane means continuous loading with the maximum weight on the hook for 3 shifts per day, 365 days per year (i.e. in continuous mode) in an open trestle warehouse ramp.
- control - from a closed cabin equipped with air conditioning;
- lifting device - hook / magnetic washer (removable) with independent cable drum;
- crane lighting - 4 LED lamps with a power of 100 W each;
- power supply of the crane trolley - cable current lead, along the I-beam profile;
- crane supply along the overpass - the Customer’s existing cable power supply;
- load limiter (based on strain gauges);
- parameter recorder;
- electric motor shields;
- vacuum circuit breakers;
- uninterruptible power supply magnet;
- limit switches of the lifting / lowering mechanisms of the load gripping device, movement of the crane truck and crane;
- anti-theft seizures;
- limit switches of the entrance to the cabin, exit to the crane gallery and crane service area;
- crane runway - rails KR-70.
Thus, a project was successfully implemented to replace the existing obsolete bridge crane as part of the modernization of the transfer process of the grinding bodies of the ball warehouse, which made it possible to organize uninterrupted lifting and transport work at this section of the mining and processing plant for at least twenty years.