Study on Wear of Scraper Conveyor Chute

Abstract

The wear of the middle trough of coal mine scraper conveyor, is a common fault of scraper conveyor. Starting with the causes of wear by analyzing the structure and the working condition of the chute, it indicates that the friction is the main cause of the chute wear, and abrasive wear, adhesive wear, fatigue wear and corrosion wear are the main forms of chute failure. The use of new materials and strengthening the maintenance can prevent the chute wear of scraper conveyor and improve service life. Introduction Because of the high structural strength, the large transport capacity, the bending capacity and moving easily, the scraper conveyer is widely used in the production of coal mine. Chute is one of the main components of scraper conveyor and the middle groove is not only the principal part of the chute, but also the main energy consumption and wear part, whose abrasion and corrosion failure could lead to the jump chain clamping phenomenon and causing chain scission, motor overload and even burning motor, resulting in serious economic losses. This paper analyses the wear condition of the middle trough of SGW-44 type scraper conveyor, and put forward the measures of improvement. The composition and structure of the chute The chute of scraper conveyor is used for bearing the body and as a track for shearer. Chute has regulating tank, connecting tank and mostly, the middle groove. The middle groove is welded by channel steel and median plate, as shown in figure 1. The upper grooves are bearing grooves for the shipment of materials, and the lower grooves have two type: one has the openings at the bottom and the other hasn’t, which are all used for the return and back of the scraper chain. The types of the middle groove are single type, edge double chain type and double chain type. The SGW-44 type uses edge double chain and its sectional form of channel steel is the type M. Fig.1 The middle groove 1, 2--high manganese steel protruding side; 3—channel steel; 4—bearing; 5—mediun plate; 6, 7—high manganese steel concaving side. International Conference on Intelligent Systems Research and Mechatronics Engineering (ISRME 2015) © 2015. The authors Published by Atlantis Press 2254 Chute condition and main fault The working principle is that using the infinite loop of the scraper chain around the nose sprocket and the tail sprocket as traction mechanism, using the chute as bearing mechanism, when the motor is started, the hydraulic coupler and the speed reducer drive the chain wheel to rotate, thereby driving the scraper chain into continuous operation, then, the cargo installed in the chute will be transported to the head from the tail, as shown in figure 2. Fig.2 Scraper conveyor structure diagram 1-Motor; 2Hydraulic couplers; 3-Reducer; 4-Transitional chute; 5-middle groove; I-chain-drive section;II-rear part; III-middle part. SGW-44 type scraper conveyor chute material for 16Mn hot-rolled plate, at work due to compression, tension, bending, by shock, friction, vibration, corrosion and other effects, therefore, wear is the main failure. Cause analysis The surface where the two are in contact or in relative motion, are not to have friction, a friction wear occurs. Therefore, the friction material chute and transportation are the main reasons to cause the chute abrasion. Many wear type, SGW-44 type scraper conveyor chute wear mainly in the form of: Abrasive wear. Abrasive wear generally refers to hard abrasive or projection machine parts in contact with each other in the process of the surface, the surface material of a kind of phenomenon of loss or process. Scraper chain surface along the chute in runtime, the convex surface body, chain and chain chute between hard particles wear of the chute are abrasive wear, hardness higher link and soft chute slide correspondingly, microcosmic performance for a lot of asperity contact, during which the abrasive is coal, gangue and metal particles and corrosion the product, as the main abrasive or coal and gangue mineral is hard, by scanning electron microscope, the chute chain channel morphology preliminary think: in addition to abrasive cause chute on chip form outside the main mechanism of spalling, plowing the plastic deformation. Clip in the chain and between the sheets in the coal and gangue, also can produce micro cutting and stripping of the chute. Depths of surface/mm Fig.3 Changes of the hardness along with the depths of surface According to the classification of abrasive wear, that is three body abrasive wear, abrasive only about 10% of the time is generated on the surface of the sliding, wear. Coal and gangue clip relative