PRODUCT CATEGORIES

Vacuum Heat Treatment Furnace

Vacuum Sintering Furnace

Vacuum Brazing Furnace

Fixture Fastener application

Fasteners are a type of mechanical parts that are used for fastening connections and are widely used. All kinds of fasteners can be seen on various machinery, equipment, vehicles, ships, railways, bridges, buildings, structures, tools, instruments, meters and supplies. It is characterized by a variety of specifications, different performance and uses, and the standardization, serialization, and generalization of the species are also extremely high. Therefore, some people refer to a type of fastener with existing national standards as standard fasteners, or simply standard parts. Fasteners are the most widely used mechanical basic parts.

Fastener production
The most important link in the development and design of fasteners is quality control. There are several major gates from feeding to finished product shipment, and these major gates have different inspection methods. First of all, the feed is related to appearance, size, element, performance, hazardous substance detection, etc .; the process is more about appearance, size, knocking experiment, forging streamline; heat treatment is more about appearance, hardness, torque, tensile , Metallography, etc .; the surface treatment is more of some hydrogen embrittlement testing, coating, salt spray, etc., including a hazardous substance detection when shipped. In the size and appearance inspection, the common ones are the second element, the contour measuring instrument, the coordinate measuring instrument, and the image sorting machine (this is a full selection machine); for the mechanical and chemical testing, there are mainly hardness machines (Rockwell and Vickers ), Tensile machine, metallographic microscope; on the material detection, there is a spectrum analyzer, salt spray test machine.

It usually includes the following 12 types of parts:
1. Bolt: a type of fastener consisting of a head and a screw (a cylinder with an external thread), which needs to cooperate with a nut to fasten and connect two parts with through holes. This form of connection is called a bolt connection. If the nut is unscrewed from the bolt, the two parts can be separated, so the bolt connection is a detachable connection.

2. Stud: a type of fastener that has no head and only has threads on both ends. When connecting, one end of it must be screwed into a part with an internal threaded hole, the other end passes through a part with a through hole, and then screw on the nut, even if the two parts are tightly connected to form a whole. This type of connection is called a stud connection, which is also a detachable connection. It is mainly used in the occasions where one of the connected parts is thick and requires a compact structure, or due to frequent disassembly, it is not suitable to use bolt connection.

3. Screw: It is also a type of fastener composed of a head and a screw. It can be divided into three categories according to the purpose: machine screws, set screws and special purpose screws. The machine screw is mainly used for a tightening connection between a part with a threaded hole and a part with a through hole, which does not require a nut fit (this connection form is called a screw connection and is also a detachable connection; it can also It is used with nuts to fasten the connection between two parts with through holes.) Set screws are mainly used to fix the relative position between two parts. Special purpose screws, such as eye bolts, are used for lifting parts.

4. Nut: with internal threaded hole, the shape is generally flat hexagonal column, flat square column or flat cylinder, with bolts, studs or machine screws, used to fasten and connect two parts, making it into One piece.

5. Self-tapping screws: similar to machine screws, but the thread on the screw is a special thread for self-tapping screws. It is used to fasten and connect two thin metal components into one piece. The component needs to be made with small holes in advance. Due to the high hardness of this screw, it can be directly screwed into the hole of the component to make the component Internal thread forming response

6. Wood screw: It is also similar to the machine screw, but the thread on the screw is a special wood screw thread, which can be directly screwed into a wooden component (or part), used to put a metal (or non-metal) with a through hole The part is tightly connected to a wooden component. This connection is also detachable.

7. Washer: a type of fastener with an oblate ring shape. It is placed between the supporting surface of bolts, screws or nuts and the surface of the connected parts, which increases the contact surface area of the connected parts, reduces the pressure per unit area and protects the surface of the connected parts from being damaged; It can also prevent the nut from loosening.

8. Retaining ring: It is installed in the shaft groove or shaft hole groove of the machine and equipment, and plays the role of preventing the parts on the shaft or hole from moving left and right.

9. Pin: It is mainly used for positioning parts, and some can also be used for connecting parts, fixing parts, transmitting power or locking fasteners.

10. Rivet: a type of fastener consisting of a head and a nail rod, used to fasten and connect two parts (or components) with holes to make it a whole. This form of connection is called rivet connection, or riveting for short. It is a non-removable link. Because if the two parts connected together are separated, the rivets on the parts must be destroyed.

10. Components and connection pairs: Assemblies are a type of fastener supplied in combination, such as a combination of a machine screw (or bolt, self-supplied screw) and a flat washer (or spring washer, lock washer); connection vice A type of fastener supplied by a combination of a special bolt, nut and washer, such as a steel structure with a high-strength large hexagon head bolt connection pair.

12. Welding nails: heterogeneous fasteners composed of nail rods and nail heads (or no nail heads), which are fixedly connected to one part (or component) by welding, so as to be connected with other parts.

Fasteners suitable for marine applications
The fixings and fasteners are made of corrosion-resistant brass and stainless steel
Fastener suppliers providing fastener products suitable for marine applications need to consider materials suitable for marine environments. Both A2 and A4 use stainless steel; brass and marine brass; and the coating also plays an important role. Modern zinc flakes and plastic coatings have surface treatments with high salt spray performance, and it is more difficult to obtain supplements from traditional cadmium coatings.