In the production operations of the mine, the conveyor belt system is a key link in material transportation. As an important part of the conveyor belt drive device, the TKM48 hypoid gear reducer, its correct operation and installation are of vital significance to ensure the stable operation of the conveyor belt, improve production efficiency and reduce maintenance costs. This article will use a practical case to explain in detail the installation and installation process of the KM48 hyperboloid gear reducer on the mine conveyor belt.
2. Project background
A large mine needed to upgrade one of its main ore conveyor belts. The conveyor belt has a conveying length of 500 meters, a bandwidth of 1.2 meters, and a conveying speed of 2.5 m/s, the conveyed material is ore, the maximum bulk density is 2.5 tons/cubic meter, the working environment is relatively harsh, there is dust, moisture and certain vibration.
3. Selection process
Calculate load torque
First, the load torque of the conveyor belt needs to be calculated. According to the formula: Torque = Force × Moment Arm. On a conveyor belt, the force mainly consists of the gravity and friction of the material.
Gravity of material = volume of material × bulk density × acceleration due to gravity
Material volume = bandwidth × belt length × material thickness
Assuming the material thickness is 0.2 meters, the material volume = 1.2 meters × 500 meters × 0.2 meters = 120 cubic meters
Friction force = friction coefficient × normal pressure
Assuming that the friction coefficient is 0.3 and the positive pressure is equal to the gravity of the material, the friction force = 0.3 × 2940 kN = 882 kN
The moment arm is the radius of the drum, assumed to be 0.3 meters
Then load torque = (2940 + 882) kN × 0.3 m = 1146.6 N·m
Consider starting and braking torque
Since the conveyor belt will produce a large torque impact during starting and braking, a certain safety factor needs to be considered. Generally, the starting torque is 1.5 - 2 times the load torque, and the braking torque is 1.5 - 2 times the load torque. 1.2 - 1.5 times. Assuming that the starting torque coefficient is 1.8 and the braking torque coefficient is 1.3, then the starting torque = 1146.6 N·m × 1.8 = 2063.88 N·m, braking torque = 1146.6 N·m × 1.3 = 1490.58 N·m
Determine the rated torque of the reducer
According to the calculated load torque, starting torque and braking torque, the rated torque of the selected TKM48 hypoid gear reducer should be greater than the maximum torque, that is, the starting torque. Taking into account a certain margin, select the rated torque as 2500 N·m reducer.
Determine the reduction ratio of the reducer
Calculate the reduction ratio of the reducer based on the conveyor speed of the conveyor belt and the rotation speed of the drive motor. Assume that the speed of the drive motor is 1450 rpm, the conveyor speed of the conveyor belt is 2.5 m/s, and the diameter of the roller is 0.6 meters, then the reduction ratio = motor speed × 60 × drum circumference/conveying speed = 1450 × 60 × π × 0.6 / 2.5 ≈ 6670
Consider work environment and other factors
Due to the harsh working environment of the mine, which is dusty, moist and vibrating, it is necessary to choose a reducer with high protection level, good sealing performance and strong vibration resistance. At the same time, factors such as the installation method and maintenance convenience of the reducer also need to be considered.
