Fasteners are one of the most widely applied mechanical foundation pieces. Along with our country acceded to the wto in 2001 and into the international trade of the nation's ranks. China fastener products massive exports to countries all over the world, all over the world also constantly fastener products into China market. As our country exports into larger fasteners of one of the products, achieve and the international community, to the promotion of China's fasteners enterprise to the world, promote fasteners enterprise fully participate in international cooperation and competition, and has an important significance in that and strategic significance.
Fasteners is to combine two or more than two parts (or components) fastening a see whole USES a class the floorboard of the mechanical parts. The characteristics of variety specification is fastener various, performance and usage each different, and standardization and serialization, generalization degree is extremely high, so some of the national standards of fasteners has called standard fasteners, or referred to as standard parts.
Screw the wide range of users of group of distribution:
Current global fasteners mainly used in automobile industry, electronic industry and construction and maintenance industry. Among them, the auto industry is the biggest user demand, however, accounts for about 23.2% of total sales in the fastener; Next is the maintenance industry market and building industry, accounts for about 20% of total sales in the fastener; The third is the electronics industry, accounts for about 16.6% of total sales fasteners.
It usually include the following 12 parts:
1. Bolt: the head and screw (with a male cylinder) two parts of a class of fasteners, and to the nut cooperate, used for fastening two with a hole parts. This kind of connection form says bolt connection. Such as the nut
from bolts topspin, can make the two separate parts, it is to belong to bolt connection can remove the connection.
2. Studs: no head, only ends are to go a thread fasteners. Connected, it must be with one end of the batter in the spare parts of the threaded hole, and in another end through the hole with of the components, and then screw on the nut
s, even if the two parts as a whole saw fastening. This kind of connection form called studs connection, also is to belong to removable connection. Mainly used to be connected parts of bigger, request the thickness of the structure is compact, or because remove frequent, unfavorable use bolt connection occasion.
3. Screw: also by the head and screw two part of a class of fasteners, according to use can be divided into three types: machine screw, tight set screws and special use screws. Screw machine is mainly used for a tight set threaded hole parts, and with a hole between parts of the fastening, do not need to cooperate with nut (this kind of connection form called screw connection, also belong to removable connection; also can cooperate with nuts, used for two with a hole between parts of the fastening.) Tight set screw mainly used for fixed two parts of the relative position between. Special use screws for example have rings for hoisting parts with screw, etc.
: with female threaded hole, general shape is shown for flat six JiaoZhu form, also have show flat square column shape or flat cylindrical, non-standard fasteners, with bolts, studs or machine screws, used for fastening two parts, make it become a whole.
5. Tapping screws, machine screws and similar, but screw thread in the for special self-drilling screws with threads. Used for fastening two thin metal components, make it become a whole, members need to make holes in advance, because the screw had taller hardness, can direct the batter the hole in the component, formed in the response of the component internal threads. This kind of connection form also is to belong to removable connection.
6. Wood screws, machine screws and is similar, but screw thread in the special for the wood screws with rib, can direct the batter woodiness members (or parts), used to a belt through holes in the metal (or non-metallic) parts and a wooden fastening components together. This connection is also belong to can remove the connection.