Improvement measures and maintenance of wear of sprocket component of scraper board
Sprocket ComponentsService life is short, far from the requirements of production practice, according to the use of sprocket, processing status, manufacturing process, the sprocket proposed some improvement measures:
（1) The original sprocket design material is40Cr, the overall quality modulation hardnessHB220~250, Tooth quenchingHRC48~52。 This method is limited by the quenching hardness of the tooth part, on the basis of which the wear resistance of the sprocket is basically not enhanced. It is recommended that the sprocket material be changed to20CrMnTi, carburizing quenching treatment, chain fossa hardness up toHRC60Above, its abrasion resistance is40Crof the material2.5More than double. This can greatly enhance the service life of the sprocket, reduce the frequency of repair machine, enhance productivity and reduce production costs;
（2) The shape of the original sprocket chain is forging direct molding, so that the size of the error is large, rough surface, but also reduce wear resistance. With the good application of CNC machine tools, and the reduction of its processing costs, it is recommended to leave a small amount of residual after forging, by several milling to complete the finishing process, in order to improve dimensional accuracy and surface roughness, so as to achieve the goal of enhancing wear resistance.
Maintenance and Repair
1, sprocket tightness to be appropriate, too tight will increase power consumption, bearings easy to wear; too loose the sprocket easy to beat and remove the chain. The degree of tightness of the sprocket is: lifted or pressed from the middle of the sprocket, about the spacing between the two sprockets2%－3%。
2, the sprocket should be mounted on the shaft without swinging and skew. In the same transmission assembly, the end surface of two sprockets should be located in the same plane, and the sprocket is spaced in the0.5When the meter is below, you can deviate1mm; the spacing in the sprocket0.5When the meter is above, it can deviate2Mm. However, there can be no friction sprocket tooth side phenomenon, if the two-wheel offset is too large easy to produce debonding and accelerated wear. Care needs to be taken to check and adjust the offset when replacing the sprocket.
3, after the sprocket wear is serious, should replace the newer sprocket and the new sprocket at the same time, in order to ensure the good meshing. You cannot replace a new sprocket or a new sprocket alone. Failure to do so will cause poor meshing to accelerate the wear of new sprockets or new sprockets. When the sprocket tooth surface is worn to the extent, it should be used in time (refers to the sprocket used by the adjustable surface) to make the use of the time become longer.
4, the new sprocket is too long or elongated after use, it is difficult to adjust, can see the situation to remove the chain section, but need to be even. The chain section should pass through the back of the sprocket, the lock is inserted outside, and the opening of the locking sheet should be in the opposite direction of rotation.
5, sprocket in the work should be in time to add lubricating oil. Lubricating oil must enter the matching gap between the roller and the inner sleeve to improve the working conditions and reduce wear.
6, the old sprocket can not be mixed with some of the new sprocket, otherwise it is easy to produce impact in the transmission, pull off the sprocket.
7, when the machine is stored for a long time, the sprocket should be removed and cleaned with kerosene or diesel, and then coated with oil or butter to store in a dry place.