2020-08-25 06:57:54 1054
The main bearings of the jaw crusher mostly use open sliding bearings, and once the scraping is not good, it will cause tile grinding or tile burning accidents. Therefore, Gold Mine will give you a lecture today about the knowledge of the jaw crusher scraping and grinding the main bearing bush.
The technology of bearing bush scraping should achieve that the main shaft and the bearing bush must be in uniform and close contact, and there must be a certain matching clearance, so that the upper and lower bearing bushes and the main shaft outside the contact angle form an oil wedge, and the wedge shape starts from the bush mouth. The value gradually transitions to zero. The contact angle should not be too large or too small. If the contact angle is too small, the bearing pressure will increase, and in severe cases, the bearing will produce greater deformation, accelerate wear, and shorten the service life. If the contact angle is too large, it will affect The formation of oil film destroys the lubrication effect. Therefore, under the premise of not affecting the bearing pressure conditions, the smaller the contact angle, the better the actual contact spots within the contact angle range, the finer and more uniform the better. The scraping of the bearing should be The shaft is the benchmark, and the two use the inner hole scraper to scrape after the grinding. The process of scraping the tile is to scrape the tile first, then scrape the tile initially, then scrape the entire tile, and finally scrape the side clearance and the oil storage point. Scraping can generally be divided into three processes: coarse scraping, fine scraping and fine scraping. When scraping, the principle of taking heavy first, light scraping, heavy leaving light, large and small should be adopted. When scraping the bearing bush, not only make the contact point contact The angle meets the technical requirements, and the top and side clearance must reach the specified value. The scraping of the main bush can be divided into the thick and fine scraping of the upper and lower bushes, the fine scraping of the upper and lower bushes, and the scraping of the side clearance and the oil storage point.
The thickness and fine grinding of the upper and lower bushes are first to install the two lower bushes in the bearing housing, and then apply a layer of display agent (such as Hongdan pink oil, etc.) on the spindle, and install the spindle Put it in the bearing and turn it two or three times in the forward and reverse directions, then take out the main shaft, and rough scrape according to the distribution of the colored points on the bearing. The positive rake angle can be used in the rough scraping stage. The hand can be heavier in the first few passes. Scrape off some metal to speed up the scraping process. When the contact area reaches 50%, it is time to scrape. In the fine scraping stage, a small rake angle can be used to scrape. The blade should be at a 45 angle to the centerline of the bearing bush. Do not use force when scraping Too large to prevent ripples in the blade. The scraped blade should cross left and right until the contact spots within the contact angle range are evenly dense, and the spindle level error is between 0.2mmm. The method and requirements of the thickness of the upper tile and the lower The requirements for the thickness and grinding of the tiles are basically the same. The difference is that the upper and lower tiles are placed above the main shaft for grinding.
Fine grinding of the upper and lower tiles After the upper and lower tiles are subjected to coarse and fine grinding, the contact spots are still If the size is large, further refinement is required. First, add a socket gasket on the joint surface of the upper and lower tiles, install the positioning pin of the upper tile of the spindle and tighten the screws, make the spindle rotate a few times in the normal direction of rotation, and then remove the upper tile and hoist it away Spindle, for fine grinding work. When scraping, it is recommended to scrape with a negative rake angle until the contact spots on the contact surface meet the technical requirements.
After the fine scraping of the side clearance and the oil storage point is completed, The side clearance and the oil storage point should be scraped. When scraping the side clearance, a part of the two ends should be left to prevent the oil from flowing out of both sides of the bush, so as to ensure the lubrication of the bearing bush. Between the contact part and the non-contact part of the bush, it should be Make it gradually transition Obvious limits are not allowed. Then scrape the oil storage point on the contact arc surface of the bearing bush. The oil storage point is used to store lubricating oil. The oil storage point can be round or flat. The depth is generally 0.30.5mm and the area is 1530mm2, the total area should not exceed the scraping oil storage point on the contact arc surface. The oil storage point is used to store lubricating oil. The oil storage point can be round or flat, the depth is generally 0.30.5mm, the area is 1530mm2, and the total area It should not exceed 15.