As the most common connecting parts, there are many types of fasteners, among which the non detachable fasteners mainly include solid rivets, pull rivets, pull bolts, lock bolts, bracket nuts (pull rivet nuts), etc. different types of fasteners will be introduced in the following Chinese standard parts.
Solid rivet: a part that uses its own deformation or interference to connect the riveted parts. Solid rivets are generally made of aluminum, copper, iron and other materials, and the surface treatment is white zinc plating. It is a kind of rigid connection with rivets, which is not detachable. Small rivets can be cold riveted, large rivets are hot riveted in the red hot state. Solid rivets can be widely used in cutting tools, stationery account books, locks, helmets, automobile Hardware bags, baby carriages, automobile clutch steel plates, motorcycle accessories and household appliances.
Pull rivet: it is a kind of rivet for single-sided riveting, but it must be riveted with special tools - pull riveter (manual, electric, pneumatic). During riveting, the rivet core is pulled by a special riveting gun, which makes the rivet body expand and plays a riveting role. This kind of rivet is especially suitable for riveting occasions where it is inconvenient to use ordinary rivets (it must be riveted from both sides), so it is widely used in construction, automobile, ship, aircraft, machinery, electrical appliances, furniture and other products. Open end blind rivets with flat and round head are the most widely used. Countersunk blind rivets are suitable for riveting where the surface needs to be smooth. Closed type blind rivets are suitable for riveting where high load and certain sealing performance are required.
Pull bolt: generally, the round steel bolt with two ends of thread is used for the pull bolt, also known as the through wall bolt, and the long holes at both ends of the flat steel are also used to insert and fix the wedge with wedge iron. Because bolt is also a kind of railway fittings, railway fittings are an integral part of railway lines. The track referred to here includes rail, sleeper, connecting parts, track bed, anti climbing equipment, rail support and turnout, etc. As an integral engineering structure, the track laid on the subgrade plays a guiding role in the train operation, and directly bears the huge pressure of the rolling stock and its load.
Lock bolt: a lock bolt is composed of lock cylinder, lock body, lock wall and bolt. The utility model uses the combination of bolt and lock body to prevent the outdoor facilities from being easily disassembled and stolen, so as to improve the safety and firmness of the user facilities.
Bracket nut: it is a fastener that can install the nut on the aircraft parts in advance, but does not need to use tools to fix the nut when installing the screw or bolt. It is usually composed of a self-locking nut and a bracket supporting the nut. If the nut and the bracket are integrated, they are called fixed bracket nuts; if the nut is clamped on the bracket, they are called floating bracket nuts. There are 1 large, 2 small and 3 holes on the support plate of the support plate nut, of which the large hole is used for the installation of subsequent screws, and 2 small installation holes with a diameter of 2.38mm are used for the installation of the support plate nut on the components.