论文部分内容阅读
目前各类磨床油缸与活塞的密封,大多采用O形密封圈。O形密封圈虽有结构简单、装拆容易、更换方便等优点,但也存在一些缺点: (1)以O形圈为密封件的活塞与油缸,一般采用H8/f8间隙配合。为了使O形圈有预压缩量,O形圈放入活塞槽后总是略高于活塞外圆表面。不过,因制造O形圈的橡胶的弹性模数极低(E=8MPa),不能承受活塞与活塞杆重量的下垂。当装进油缸后活塞的下半部表面就直接与油缸壁接触,所有配合间隙均在活塞上半部与油缸壁之间,总装配时不能作到活塞、活
At present, all kinds of grinder cylinder and piston seal, most of the O-ring. Although O-ring has the advantages of simple structure, easy assembly and disassembly, easy replacement, etc., there are some disadvantages: (1) Pistons and cylinders with O-ring as the seal usually adopt H8 / f8 clearance fit. In order for the O-ring to be precompressed, the O-ring is always slightly above the outer surface of the piston after it has been placed in the piston groove. However, due to the very low elastic modulus (E = 8 MPa) of the rubber used to make the o-rings, the weight of the piston and piston rod can not be sagged. When installed into the cylinder after the piston on the lower half of the surface directly contact with the cylinder wall, all with the gap between the upper half of the piston and cylinder wall, the total assembly can not be made of piston, live