Set of parts processing

Set of parts and the kinds of structure: set of parts according to their structural characteristics can be divided into integral type and open type two sets of parts technical requirements: 1) Within the inner hole Kong Shi plays a role of supporting fire guide sleeve parts the main surface. Inner hole diameter size tolerance level for IT7 commonly, precision shaft sleeve sometimes take IT6, hydraulic cylinder inner hole take IT8 commonly, if match on the piston sealing ring, can be reduced to IT9. The surface roughness is commonly Ra1. 6 ~ 0. 1; Demanding for commonly: Ra0. 042). Cylindrical outer diameter tolerance grade is generally IT6 ~ IT7; The surface roughness in Ra3. 2 to 0. 43) Alignment between inside and outside the circle when the inner hole of the final processing is the set of pressure into the box body or stand last in line, set of internal and external circular shoulder alignment requirements is low; If the set of the final machining is completed before the assembly, both inside and outside circular coaxial degree the demand is higher, generally is 0. 01 ~ 0. 05. 4) End of the hole axis and the vertical degree of end face at work if carry axial load, or as a locating datum in the process, end face and the hole axis perpendicularity requirement is higher, generally is 0. 02 ~ 0. 5 sets of parts material and the blank: material: general set of parts made from steel, cast iron, bronze and brass. Some sliding bearing with double metal structure to coat on the lining of the centrifugal casting method in steel casting bronze, lead, tin bronze or the type of alloy bearing alloy materials, such as to improve the bearing capacity and service life. Blank: aperture smaller sleeve, generally choose the hot rolled or cold drawn bar, also USES solid casting. Aperture is large, often using perforated castings and forgings or seamless steel tube. To some thin wall bearing bending bimetallic materials available. When mass production, can use cold extrusion and powder metallurgy and other advanced manufacturing technology. Set of parts processing and main technological problems 'to the inner hole machining accuracy and surface roughness requirements, ensure that the inner hole and cylindrical surface position accuracy between sets of parts processing order has two options: the first is a cylindrical as the final processing, begin with cylindrical rough machining, rough and finish machining inner hole again finally finishing cylindrical. This scheme suitable for the surface of the cylindrical surface is the most important set of parts. The second solution is to put the inner hole as a final treatment plan, first starting from the inner hole rough machining, rough and finish machining cylindrical again, finally finishing hole. This scheme suitable for inner hole surface is one of the most important parts.