Application of plasma surfacing technology in coal mine machinery industry

       my country's coal industry is one of the pillar industries of the national economy. While producing energy, it also consumes a lot of resources. How to improve the utilization rate of resources, extend the service period of equipment and reuse of scrap equipment, is the direct economic benefit of the coal industry. Increasing social benefits is a very important aspect. Because coal mine machinery and equipment are operated underground, the production environment is relatively harsh, equipment failures occur frequently, and the space for maintenance operations is narrow. Many of them cannot be replaced and repaired underground, which invisibly increases the difficulty of mechanical equipment maintenance, and then A typical example is the central trough that affects the smooth production of coal mines. Therefore, the use of plasma surfacing remanufacturing technology in the coal industry to improve the surface performance of vulnerable parts and prolong the service life is of special significance.



1. The middle slot of the scraper conveyor



The middle trough is mainly used for scraper conveyors and transfer machines in coal mines. During use, the middle groove is scratched by scrapers and chains and abrasive particles from coal. The surface without abrasion treatment is easily worn into pits and fails. The large number of middle tanks used and the large amount of maintenance are the outstanding problems to be solved. The implementation of remanufacturing in maintenance will produce obvious economic benefits.



The use of powder plasma surfacing technology is the best process for repairing the middle groove of the scraper conveyor.



Powder plasma surfacing is an advanced technology of surface cladding alloy using argon plasma arc as high temperature heat source and alloy powder as filler metal. It is one of the new surface hardening methods. It has the following characteristics:



(1). Higher productivity.



(2). Good quality and process stability of the surfacing layer.



(3) The surfacing welding process is pollution-free and automatic, realizes mechanization and automation, and reduces labor intensity.

Using CNC plasma surfacing welding of high carbon and high chromium alloys, the hardness of the surfacing layer is greater than HRC58, and there are a large number of chromium carbide hard phases in the surfacing layer, so it has excellent wear resistance. After treatment, the service life should be increased by 3-5 times.

2. Hydraulic prop plunger



The hydraulic prop is the most widely used equipment in the mine. As an important part of the whole machine-the hydraulic cylinder plunger, it is subject to environmental corrosion and scratches during operation. The plunger of the hydraulic prop used in the mine used to be chrome-plated. , Because the chromium plating layer is very thin, the corrosion resistance and scratch resistance are very poor, and the service life is short, generally only 2-3 years. Due to the serious environmental pollution caused by chrome plating, it has been banned. At present, the laser cladding process is used to repair hydraulic props. Although this process is good, the equipment is expensive, the maintenance is more complicated, and the operating cost remains high.



The plasma surfacing method is used to surfacing wear-resistant alloys on the surface of the plunger. It has a series of advantages such as high production efficiency, low operating cost, stable process, and easy control. The application machine has outstanding advantages.