What is the difference between roller chain and belt drive in maintenance?

What is the difference between roller chain and belt drive in maintenance?

There are the following differences in maintenance between roller chain and belt drive:

1. Maintenance content

Roller chain

Sprocket alignment: It is necessary to ensure that the sprocket is installed on the shaft without skew and swing, and the end faces of the two sprockets in the same transmission assembly should be located in the same plane. When the sprocket center distance is less than 0.5 meters, the allowable deviation is 1 mm; when the sprocket center distance is more than 0.5 meters, the allowable deviation is 2 mm. If the sprocket is offset too much, it is easy to cause chain derailment and accelerated wear. For example, when replacing or installing the sprocket, carefully adjust the position of the sprocket and use special measuring tools to ensure the alignment accuracy of the sprocket.
Chain tightness adjustment: The tightness of the chain is very important. Lift or press down from the middle of the chain, about 2% – 3% of the center distance between the two sprockets is the appropriate tightness. If the chain is too tight, it will increase power consumption and the bearings will be easily worn; if it is too loose, the chain will easily jump and derail. The tightness of the chain needs to be checked regularly and adjusted according to the actual situation, such as by changing the center distance or using a tensioning device.

Lubrication: Roller chains need to be kept well lubricated at all times. The lubricating grease should be distributed to the gap of the chain hinge in a timely and even manner. It is generally not recommended to use heavy oil or grease with high viscosity because they are easy to clog the hinge gap with dust. The roller chain should be cleaned and decontaminated regularly, and the lubrication effect should be checked. For example, for some roller chains working in harsh environments, it may be necessary to check the lubrication every day and replenish the lubricating oil in time.
Wear inspection: Check the working surface of the sprocket teeth frequently. If the wear is found to be too fast, adjust or replace the sprocket in time. At the same time, check the wear of the chain, such as whether the elongation of the chain exceeds the allowable range (generally, the chain needs to be replaced if the elongation exceeds 3% of the original length).
Belt drive

Tension adjustment: The belt drive also needs to adjust the tension regularly. Since the belt is not a completely elastic body, it will relax due to plastic deformation when working in a tensioned state for a long time, which will reduce the initial tension and transmission capacity, and even cause slippage in severe cases. Common tensioning methods include regular tensioning and automatic tensioning. Regular tensioning is to increase or decrease the center distance by adjusting the screw so that the belt reaches the appropriate tension. Automatic tensioning uses the deadweight of the motor or the spring force of the tensioning wheel to automatically adjust the tension.
Installation accuracy inspection: When parallel shafts are driven, the axes of each pulley must maintain the specified parallelism. The grooves of the driving and driven wheels of the V-belt drive must be adjusted in the same plane, and the error must not exceed 20′, otherwise it will cause the V-belt to twist and cause premature wear on both sides. During installation and maintenance, use tools such as a level to check the parallelism of the shaft and the alignment of the grooves.
Belt replacement and matching: When a damaged V-belt is found, it should be replaced in time. New and old belts, ordinary V-belts and narrow V-belts, and V-belts of different specifications cannot be mixed. Moreover, when multiple V-belts are driven, in order to avoid uneven load distribution of each V-belt, the matching tolerance of the belt should be within the specified range. For example, when replacing the V-belt, carefully check the model and specifications of the belt to ensure that the size of the new belt is consistent with the old belt, and when installing multiple belts, ensure that their tightness is consistent.

2. Maintenance frequency

Roller chain
Due to the high lubrication requirements of roller chains, especially when working in harsh environments, lubrication inspection and replenishment may be required every day or every week. For the tightness of the chain and the alignment of the sprocket, it is generally recommended to check once a month. In some high-intensity working environments, it may be necessary to check the elongation of the chain and the wear of the sprocket more frequently, such as once every two weeks.

Belt drive
The frequency of checking the tension of the belt drive is relatively low, and it can generally be checked once a month. For the wear of the belt, if it is a normal working environment, it can be checked once a quarter. However, if the belt drive is under high load or frequent start-stop working conditions, the inspection frequency may need to be increased to once a month.

3. Maintenance Difficulty

Roller Chain
The maintenance of the lubrication system is relatively complicated, especially for some roller chain transmission devices that use oil bath lubrication or pressure lubrication. It is necessary to regularly clean the impurities in the lubrication system and ensure the sealing of the lubrication system. The alignment of the sprocket and the adjustment of the chain tightness also require certain technical knowledge and tools, such as the use of sprocket alignment instruments and tension meters for precise adjustment.

Belt Drive
The maintenance of belt drive is relatively simple, and the adjustment of the tensioning device is relatively easy. It is also convenient to replace the belt. Just remove the damaged belt according to the prescribed steps, install the new belt and adjust the tension. Moreover, the structure of the belt drive is relatively simple, and generally no complex tools and equipment are required to complete daily maintenance.