VDMA

INDIA 2018

Best of Germany 2014 - Mining Equipment and Mining Technology

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VDMA 34 VDMA MINING SUPPLEMENT • 2018 The (water-based) hydraulic systems in various high-pressure plunger pump applications, especially longwall roof supports, are getting larger and larger. As a result, longwall operators are using multiple, large triplex pumps given that the volume flow of these pumps is limited by design and the high pressures involved. And, the cylinder size is limited by cavitation, which implies that it makes sense to produce triplex pumps with ratings of "only" about 400 kW. KAMAT has now taken the next step and developed, on the ba- sis of the thoroughly redesigned triplex pumps, the first quintuplex (five-cylinder) pumps with a rating of 530 or 800 kW and the capabili- ty to reliably deliver distinctly larger volume flows than triplex pumps. The advantages for the longwall operator result from "econo- mies of scale." A large pump is working far more cost-effectively than two or three smaller ones, and clearly needs less space — an important argument in most modernization projects. A lot of detailed design work was, however, required to transfer the basic concept of the triplex design to the quintuplex pump. The crankshaft, for example, is supported by multiple bearings, and the crossheads are oil-spray lubricated rather than splash lubricated so that sufficient lubrication of the center crossheads is ensured as well. KAMAT, nevertheless, managed to keep spare parts stocking eco- nomical through the use of many parts that are common to the triplex pumps. The housing was developed and optimized by KA- MAT in close collaboration with the IFAS Institute at the Ruhr University Bochum who also simulated the thermal load of the pumps and carried out the respective optimizations. The quintuplex pumps furthermore offer the same ad- vantages as the redesigned triplex pumps. They operate at extremely low-noise and low-vibration levels and are capable of working at full operating pressure over a speed range of 10% to 100% in conjunction with speed-con- trolled drives. Thus, they can ideally be adapted to the respective volume flow requirements. The flow rate is not controlled through unloading valves in on/off technique but through an electronically controlled speed regulation of the pump. As a result, wear is significantly reduced since the pump, the pipes and the valves are subjected to far less load. The first 530-kW quintuplex pump was quickly followed by an 800-kW model. The two versions are already produced in the series, and the operators benefit from significant cost savings in terms of energy consumption and maintenance and service bills: Three 800- kW pumps — one each as a master, slave and standby unit, which is the common constellation — are able to generate even very large volume flows at pressures up to 3,500 bar at highly economical rates. In 2017, KAMAT added a quintuplex pump with a rating of 1,200 kW to the portfolio. Transporting and Charging Explosives With the increasing number of panel-caving operations, where ore is mined by conventional drill-and-blast operations, transporting ex- plosives to the loading locations and scheduling blasts are two very important underground mining issues. Many mines rely on a mixture of ammonium nitrate and fuel oil (ANFO). Production drill holes can be as long as 25 m with a diameter up to 3 inches, which means the typical round requires approximately 3,000 kg of ANFO. By lim- iting the hole-charging time and reducing the transportation costs, mines could achieve a higher level of productivity at a lower cost. Paus has developed an ANFO-charging concept that combines the transportation and charging of ANFO in one machine to extend charging capacity for one full pattern. The system is based on the Universa 50-2 with a Deutz TCD 2012 diesel engine, Posi Stop axles and a hydrodynamic drive line from Dana Spicer. The Universa 50 is equipped with an ANFO storage platform with a maximum capacity of up to 120 ANFO bags (22 kg each), a 500-l ANFO vessel, rotary vane compressor and a telescopic platform in the rear part of the machine to cover the full drilling pattern with a fixed-carrier positioning. The carrier with boom/basket at the rear is also the ideal platform for all kinds of emulsion units. An experienced driver can accomplish this changing procedure within a maximum of 5-10 minutes. In addition, the Uni 50 can be equipped with a working platform, which permits working heights above 7 m to cover 40-m 2 faces. All machines implement extended safety features. This concept enables the increase of charging time of every unit and the use of the 500-l vessel keeps the machine dimensions as compact as possible. With its famous hydraulic quick changing system, the Uni 50 can quickly switch cassettes to a scissor platform, cement mixer and sprayer, tire handler, diesel generator, loading platform, etc. High-pressure Pumps for Large Volume Flows Economies of scale: KAMAT has developed the first quintuplex (five-cylinder) pumps with a rating of 530 or 800 kW on the basis of the thoroughly redesigned triplex pumps. The Universa 50 from Paus can be equipped with a full ANFO charging platform.

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