Type of fastener
There are many kinds of fasteners, which are roughly divided into the following:
A fastener consisting of two parts, the head and the screw
(with external thread), is matched with nuts to fasten and connect two parts with through holes. This form of connection is called a bolt connection. If the nut is swirled down from the bolt, the two parts can be separated, so the bolt connection is a detachable connection.
A class of fasteners with no head and only both ends with thread. When connecting, one end of it must be screwed into the part with inner thread hole, and the other end passes through the part with through hole, then screw up the nut, even if the two parts are fastened and connected to see the whole. This form of connection is called a stud connection, and it is also a detachable connection. It is mainly used to be connected parts with a large thickness, compact structure, or frequent disassembly, which should not be used for bolt connection.
It is also a type of fastener made up of two parts of the head and screw. It can be divided into three types by use: machine screw, tightening screw and special purpose screw. The machine is mainly used for fastening a screw thread hole and fastening parts, connection between a part with a through hole, do not need to match the nut (this connection is called screw connection, also belongs to the detachable connection; can also be used for fastening with a through hole between the two parts together with the nut. ) the tightening screw is mainly used to fix the relative position between the two parts. Special use screws, such as ring screws, are used for hoisting parts.
With an internal thread hole, the shape is flat six prism, there is a flat square cylindrical or flat cylindrical, with bolts, studs or machine screws for fastening connecting two parts, make it become a whole.
Self tapping screw
It is similar to the machine screw, but the thread on the screw is a special thread for the self tapping screw. It is used for fastening and connecting two thin metal members to make it a whole. The holes on the members need to be made in advance. Because the screw has higher hardness, it can be directly screwed into the Kong Zhong of the component, so that the internal thread can be formed in the component. This type of connection is also a detachable connection.
The wood screws
Similar to machine screws, screw thread on special screw can be directly screwed into wooden components (or parts). It is used to fasten a metal part with through hole to a wooden component. This connection also belongs to a detachable connection.
In the shape of a kind of fastener oblate ring. Between the supporting surface is arranged on the bolts, screws or nuts and connecting parts surface, plays an increasing connecting parts contact surface area, reduce the pressure per unit area and protect the connected part surface is not damaged; another kind of elastic washer
, also prevents the nut loosening.
In the shaft grooves or grooves of the machine and equipment, it plays the role of preventing the left and right parts on the shaft or hole.
It is mainly used for parts positioning, and some can also be used for parts connection, fixed parts, transmission power or locking of other fasteners.
A type of fastener consisting of two parts of the head and the nail rod, which is used to fasten the two parts (or components) connected by the holes to make it a whole. This form of connection is called rivet connection, for short, riveting. Belongs to the non detachable connection. The rivets on the part must be destroyed because to separate the two parts that are connected together.