Set of parts selection of materials and technical requirements

1, the characteristics of the parts in the machine set up supporting and guiding role, mainly composed of end face, cylindrical, inner hole, parts with thin wall thickness, easy deformation, general parts diameter greater than the axial dimension. 2, set parts technical requirements set and more parts of the surface of the cylindrical to interference or excessive cooperate with frame or box hole with its support. Inner hole main guiding role or a supporting role, often with axes, main shaft, piston, valve combination, some set of end face or flange end face positioning or support load. Hole and cylindrical generally have high alignment requirements; The inner hole surface itself size accuracy and shape accuracy and surface roughness requirements; The end face and the hole axis vertical degree requirements; The size of the cylindrical surface itself, the shape precision and surface roughness requirements, etc. 3, set of parts and materials selection of parts blank, the blank depends on its structure size and material, aperture is bigger, generally choose the castings with perforated or seamless steel tube. Aperture is lesser, can choose bar or solid casting. Under the condition of mass production, to save materials, increase productivity, extrusion, powder metallurgy, craft manufacture high precision of the blank. Steel is generally selected set of materials, casting, bronze or brass material. Sliding bearing appropriate chooses the copper material, some higher requirements of sliding bearing, in order to save precious material and adopts metal structure, which USES centrifugal casting process, the steel or wall castings cast a layer of material such as babbitt, used to improve the service life of bearing. Some strength to demand higher ( Such as servo valve valve sleeve and boring machine spindle sleeve, etc. ) Selects the high quality alloy steel.