Rivet nut, also known as pull rivet nut, pull cap, is a fastener. It consists of an internal thread and an outer shell. The outer shell is usually cylindrical with a flange at the bottom. Rivet nuts do not need to be pre-tapped, and can be directly installed on thin plates, pipes and other materials, and riveted by special tools (pull rivet guns). The riveting is firm, efficient and easy to use.
The structure and working principle of rivet nuts are as follows:
Structure: Rivet nuts consist of internal threads and outer shells. The internal threads are used to connect with bolts or screws, and the outer shell is used to fix the rivet nut on the material. There is usually a flange at the bottom of the outer shell to provide sufficient riveting strength.
Working principle: Put the rivet nut into the pre-made hole, and then use the pull rivet gun to squeeze and deform the outside of the rivet nut so that the bottom of the outer shell is close to the hole wall and forms an inward concave cone structure. In this process, the internal thread of the rivet nut will expand and fit tightly with the hole wall. Finally, cut off the pull rod of the pull rivet gun to complete the riveting.
The advantages of rivet nuts are as follows:
No pre-tapping required: Rivet nuts can be directly installed on thin plates, pipes and other materials without pre-tapping, which can save time and cost.
Strong riveting: The riveting strength of rivet nuts is high and can withstand large tensile and shear forces.
High efficiency: Riveting can be done quickly using a rivet gun, and the operation is simple and convenient.
Wide range of applications: Rivet nuts can be widely used in industries such as automobiles, aviation, aerospace, electronics, electrical appliances, machinery, furniture, and decoration.
The disadvantages of rivet nuts are as follows:
Can only be used for thin plates and pipes: Rivet nuts can only be used for plates and pipes with smaller thicknesses, and are not suitable for materials with larger thicknesses.
Cannot be disassembled after riveting: Rivet nuts cannot be disassembled after riveting. If disassembly is required, the rivet nut or the material needs to be destroyed.
Common types of rivet nuts are as follows:
Open rivet nuts: There is an opening on the top of the shell of the open rivet nut for inserting the pull rod of the rivet gun.
Closed rivet nuts: There is no opening on the top of the shell of the closed rivet nut, and special tools are required for riveting.
Flat head rivet nut: The head of the flat head rivet nut is flat and flush with the material surface after installation.
Countersunk head rivet nut: The head of the countersunk head rivet nut is conical and embedded in the material surface after installation.
When choosing rivet nuts, the following factors should be considered:
Material: Choose the appropriate material according to the application environment, such as stainless steel, aluminum alloy, copper, etc.
Size: Choose the appropriate rivet nut size according to the hole diameter and thread size.
Type: Choose the appropriate rivet nut type according to application requirements, such as open rivet nut, closed rivet nut, flat head rivet nut, countersunk rivet nut, etc.