What is Permanent Part Assembly?

What is Permanent Part Assembly?Why Is It Important?

Orbitform is an expert in permanent part assembly. But you may be wondering what exactly that is, why it is important, or why you should consider it. Manufacturers and machine builders alike can stand to benefit from permanent assembly processes. Nearly every industry that puts things together uses it, and you can benefit too. So let’s take a minute to learn exactly what permanent part assembly is. When you make a product that doesn’t need to be taken apart, there are processes that will hold it together permanently. These often involve a rivet or tenon and a forming force. The source of the forming force differs depending on the process. Orbitform specializes in orbital forming, impact riveting, roller forming, and hot upset forming.


Orbital riveting and forming is a cold forming process using a peen tool held at a fixed angle to create a sweeping line of pressure around a rivet or tenon. This motion progressively forms the rivet shank down and over the top of the clearance hole with each rotation, permanently fastening the parts together. Orbital forming uses side forces to form while rotating around the entire rivet, which requires approximately 80% less force than traditional press methods. Read more about orbital riveting and forming [here] – link to blog post about orbital riveting and forming.


Impact riveting is a cold forming assembly process using pneumatic, electro-mechanical, hydra-pneumatic, or hydraulic force to install a rivet into a part assembly. Common rivets are solid, semi-tubular, and self-piercing, with each having different characteristics. Solid rivets must achieve shank swell to fill the hole before the rivet head will collapse. Semi-tubular rivets have a semi-hollow rivet shank, causing the rivet walls to curl over on forming with minimal shank swell. Self-piercing rivets do not require a pre-drilled hole and draw thin materials into anvils or die to form them. Impact riveting has very fast cycle times, making it excellent for high volume assembly. To learn more, [click here]. – link to blog post about impact riveting.


Specifically designed for large diameter cylindrical parts, roller forming is a non-impact process using a spinning roller-head with two or more rollers to apply symmetrical force to the part. Roller forming is used for flaring, forming a lip, crimping, or forming a groove in cylindrical parts too large for other processes. Though testing is recommended, it is possible to form seals in the ends of tubes using gaskets or an O-ring. Cycle times typically range from 3-5 seconds depending on the application. Forming is a consistent 360 degrees and even, making for aesthetically pleasing and strongly formed joints. Learn more about roller forming [here]. – link to blog post about roller forming


Hot Upset forming and riveting uses heat and pressure to form a fastener or tenon. Similar to electro-forging, the headed material becomes malleable and collapses under pressure applied by the Powerhead. Hot upset has increased hole fill, making it an ideal process for assembling parts that undergo high stress or vibration. Hot upset is best suited for hardened materials that cannot be formed in other ways. Read more about hot upset forming and riveting [here]. – link to blog post about hot upset forming.


Orbitform takes an unbiased approach to finding our customers the best solution for their application. With over 25 years of experience, we are experts in permanent part assembly. If you feel that you could benefit from permanent part assembly, contact us today at (800)-957-4838 or by email. Orbitform…solutions delivered.