Equipment manufacturing term: large electric excavator

Large-scale electric excavators are mainly composed of mechanical and electrical parts. The mechanical parts include: bucket, stick, boom and pushing mechanism, opening mechanism, lifting mechanism, swing mechanism, rotary platform, central pivot, roller plate, underframe, traveling mechanism, crawler device, and upper part. Components, lower part of the remaining components, pressure control system, lubrication system and lubrication room, hangar and its ventilation dust removal device, driver's room and its air conditioning, ladders, railings, walking platform, counterweight and other major parts. The pushing mechanism of the excavator adopts a gear-rack rack structure. The electric control system includes: power supply, high voltage collector ring, arrester, high voltage switch cabinet, main transformer, auxiliary transformer, low voltage collector ring, variable frequency drive motor, AFE variable frequency drive system, PLC control and integrated monitoring system, auxiliary electrical system, heating and ventilation equipment, limit protection, lighting and communication systems, cables, etc.

In the open-pit mining process, the mining excavator scoops the blasted rock or ore (or raw coal) from the working surface with a bucket connected to the bucket and lifts the bucket and turns it to the unloading position after it is dug. The material is unloaded to the tip of the dump truck or self-propelled crusher and then turned back to the work surface to complete a work cycle.

Large-scale mining excavators are mainly used for the mining of open pit mines in the metallurgy and coal industries. They are used in combination with large-tonnage mining vehicles (with a carrying capacity of 180-360 tons) or mobile crushing stations to complete surface exfoliation and mining of mines. Key equipment in large open pit mine equipment.

At present, foreign large-scale excavator producers include the United States P&H Corporation, BE Corporation, and the Russian Heavy Machinery Corporation. Among them, the United States P&H and BE companies are the most advanced and internationally competitive companies. P&H's main production of large-scale mining excavators ranks first in the world in terms of market share in the world. The technical level of products represents the contemporary international advanced level. Its product adopts rack and pinion type pushing method, which has large digging force, full bucket coefficient, good excavation stability, strong applicability, high work efficiency, high equipment reliability, easy maintenance and maintenance, and wearing parts' service life. long. Compared to the advanced nature of its mechanical structure, its electrical and control systems have been using thyristor-powered and DC motor systems for many years, which is relatively backward compared to current AC variable-frequency motors and their control systems. BE is also a world-renowned company that produces mining machinery and equipment. Its products use steel rope pushing method. The stick adopts a high-strength torsion-free structure with circular section. The newly developed product electrical system uses advanced AC frequency conversion. And its control system has good protection for the main structural parts and transmission parts of the equipment, which improves the service life of the main structural parts, transmission parts and basic parts. The whole machine has a long service life, convenient maintenance and low failure rate (especially the electrical system. And motor), high equipment outage, low operating costs.

The domestic companies that manufacture mining excavators mainly include Taizhong, Yizhong, Hengyang Hengye Heavy Machinery Co., Ltd., Fushun Excavator Manufacturing Co., Ltd., Sichuan Bangli Heavy Machinery Co., Ltd., etc., but in addition to being too heavy to independently develop large-scale mines. With excavators, other companies are mainly cooperating with foreign P&H companies and BE companies to manufacture or only produce small-scale mining excavators. Currently, they do not have independent development capabilities.