The advantages of belt pulley The advantages of belt pulley transmission are: belt pulley transmission can alleviate load impact; belt pulley transmission runs smoothly, with low noise and low vibration; belt pulley transmission has a simple structure and convenient adjustment; belt pulley transmission is not as strict for the manufacturing and installation accuracy of pulleys as meshing transmission ; The pulley drive has the function of overload protection; the adjustment range of the center distance of the two shafts of the pulley drive is larger.The disadvantages of belt transmission are: pulley transmission has elastic sliding and slipping, low transmission efficiency and inability to maintain accurate transmission ratio; when pulley transmission transmits the same large circumferential force, the outline size and pressure on the shaft are larger than meshing transmission; pulley transmission belt The life span is shorter.The diameter and other dimensions of the pulleys of all kinds of mechanical equipment are all equipped with their own pulleys and pulleys according to the reduction ratio, and they are designed according to the working speed and the speed of the motor.Working speed / motor speed = driving wheel diameter / driven wheel diameter * 0.98 (slip coefficient), such as the use of steel as the material of the pulley, the required linear speed is not higher than 40m/s, such as the use of cast iron material, the required linear speed is not higher than 35m/s, motor speed and pulley diameter conversion ratio, speed ratio = output speed: input speed = load pulley pitch circle diameter: motor pulley pitch circle diameter.The pitch circle diameter is the same as the reference diameter. Diameter -2h = pitch circle diameter. h is the depth of the groove on the reference line. Different types of V belt h are different. YZABCDE, the groove depth on the reference line is h=1.6 2 2.75 3.5 4.8 8.1 9.6.The pitch circle diameter of the pulley is the theoretical diameter of the pitch line position of the pulley, which is a bit like the index circle diameter of the gear. It is generally expressed by PD, and the outer circle is generally expressed by OD. The conversion formula of different groove pitch circles and outer circles is different, generally we It is easier to measure the outer circle of the pulley, and calculate the pitch circle according to the formula. SPZ:OD=PD+4;SPA:OD=PD+5.5;SPB:OD=PD+7;SPC:OD=PD+9.6. The minimum outer diameter of the pulley of A or SPA is 80mm. If it is smaller than this size, especially at high speed, the belt is prone to delamination and cracks at the bottom. SPZ belt, the small wheel is not less than 63mm.At the same time, pay attention to the method and tension of the belt installation, too small and easy to slip, and too large to damage the belt and bearings.Pulley specifications The specifications of the V-belt are divided by the back width (top width) and height (thickness). According to the different back width (top width) and height (thickness) dimensions, the national standard specifies the O , A, B, C, D, E and other models, each model of the V-belt has different section widths, top widths, and heights, so the pulley must be made into various grooves according to the shape of the V-belt; These different groove-type pulley pulleys determine the O-type pulley, A-type pulley, B-type pulley, C-type pulley, D-type pulley, E-type pulley and other types of pulleys.