First of all, we know that non-standard parts are proposed relative to standard parts, so before understanding non-standard parts we need to know what is meant by standard parts.
Standard parts are the common parts that have been completely standardized in all aspects such as structure, size, drawing and marking, and produced by professional factories, like threaded parts, rolling bearings and so on. In a broad sense, it includes standardized fasteners, links, transmission parts, seals, hydraulic components, pneumatic components, bearings, springs and other mechanical parts. Narrow sense only includes standardized fasteners. Domestic commonly known as standard parts is the abbreviation of standard fasteners, is a narrow concept, but can not exclude the existence of a broad concept. In addition there are industry standard parts, such as automotive standard parts, mold standard parts, etc., also belong to the broad sense of standard parts.
Non-standard parts processing professionals elaborate mainly the state did not set out strict standard specifications, no relevant parameters beyond the provisions of the enterprise free control of other accessories. There are many varieties of non-standard parts, and there is no very standard classification. Roughly classified as follows:
Metal non-standard parts.
By the customer to provide drawings, manufacturers according to the drawings using equipment to produce the corresponding products, usually the majority of molds, tolerance requirements, finish are prescribed by the customer, there is no certain paradigm. Products from casting to finishing completely need the corresponding quality control, the process is complex and variable, and the general cost is higher than standard parts.
Non-metallic non-standard parts:
It is the processing of some non-metallic materials. Such as plastic, wood, stone, etc. In recent years, the injection molding industry, the development of plastic molds increasingly sophisticated, surface design, programming CNC references, so that the cost of non-standard processing and tolerance levels have been greatly improved.
