Our company's 50O0/d production line waste heat power station coal delivery system is equipped with two BSL800-3I aggregate apron feeders to transport raw coal to the next level of TD75 belt conveyor. The two aggregate apron feeders original guide tanks are vertical drop and 800mmx700mm in diameter. The height difference between the discharging port of No.1 feeder and the belt conveyor belt is 4.17m, and that of No. 2 feeder is 3.45m. The quality of coal or coal gangue fed into aggregate apron feeders with a grate can reach about 50kg, which has a great impact on the belt and often breaks the belt, seriously affecting the safe and stable operation of production and environmental health. In June 2019, our company reformed the guide trough of aggregate apron feeders and achieved ideal results. Firstly, the guide groove of No. 2 feeder is reformed. Due to the limitations of the feeding machine floor girder and other space conditions, the guide groove can not be changed into a inclined chute, so the bottom of the vertical guide groove is designed as a diagonal, after repeated tests, and finally changed to the inclined belt running direction, dip Angle and vertical direction into a 45° Angle of inclined discharge, and keep the original caliber unchanged. In this way, the raw coal will directly impact on the bottom plate of the inclined discharge port, bounce off the bottom plate, and go out along the direction of the belt running, so that the belt, roller and shield can be protected from the direct impact of the coal block. The structure of the reformed coal transport system is shown in Figure 1.
The bottom plate of the inclined discharge port is made of 30mm thick steel plate, and 12 steel nails with Φ24mm and height of 30mm are welded evenly vertically on the plate. The impact force formed by the larger gravity of large coal plays a certain role in the initial crushing of raw coal block, and can also slow the impact wear of raw coal block on the bottom plate. A strong support frame made of 16-gauge channel steel is installed at the bottom of the bevel, and the support frame is fixed on the ground (the bottom of the guide material groove is connected with the conveyor frame of the belt conveyor). The vibration of the belt conveying frame caused by the impact of coal on the inclined bottom plate is avoided, which avoids the flying of raw coal and improves the environment of the coal conveying system.
After the technical modification, the previous fault is eliminated, so that the equipment can run safely and stably. Based on the experience, the guide groove of No. 1 feeder was reformed. Because the drop from the discharge point to the tape of aggregate apron feeders 1 is larger than that of aggregate apron feeders 2, the feeder 1 has suffered more failures due to the defect of the guide trough. Since the feeder was put into operation in May 1999, the feeder 1 has been almost idle. After the transformation of the No.1 aggregate apron feeders feeding trough, the equipment that has been idle for many years can be put into use. In this way, two aggregate apron feeders can be used interchangeably for easy maintenance and maintenance. After the transformation, the working condition of the belt conveyor has been improved, and the belt is still in use today (more than three and a half years), in good condition.
