General Considerations for Powerhead Sizing
How To Determine the Right Sized Powerhead
Posted on 06/05/2019 | by The Orbitform Blog Team
Orbital Riveting has many advantages as a permanent assembly solution. The process results in minimal shank swell, perfect for smooth articulating joints. It can also provide aesthetically pleasing finished forms as the peen tool kneads the material into place. Rivets and fasteners for orbital riveting often cost less than those required for other non-permanent assembly process.
As the experts in fastening, forming, and assembly, we know it is vital to have the right solution in order to meet your desired outcome. The wrong sized powerhead can result in reject parts and decreased throughput. Undersized powerheads can generate inconsistent finished form, longer cycle times, and work hardening of the part. Conversely, oversized powerheads use more air and electricity, take up more space, and are often not cost-effective for manufacturers.
When it comes to determining the right sized powerhead, there are many considerations. As each application is unique, so are the challenges that come with it. Below are a few general considerations when it comes to sizing a powerhead:
1.Orbitform's Solutions Lab - The most effective way to determine the appropriate size of powerhead is to test parts in our Solutions Lab. Lab technicians will assemble sample parts using our orbital riveting lab equipment. This equipment is fully equipped with process monitoring, allowing precise measurement of the force required to form the rivet.
2. Fastener- One of the most critical considerations for determining the right sized powerhead is the rivet or fastener being formed. A rivet with a higher hardness will require more force to form. For example, it takes more force to move stainless steel than it would to move mild steel. Aluminum requires even less force. The geometry of the rivet also plays a role in how much force is required to move the material. A solid rivet will require more force than a rivet with a drill point in the end. A semi-tubular rivet will require even less force.
3. Clamping- For some applications, it's important to clamp the pieces of the assembly together prior to forming. In some cases, this can be built into the fixturing. If clamping within the fixture isn't an option, a pressure pad can be added to the orbital head to clamp the part prior to forming. However, this uses up some of the force of the machine to hold the assembly together. This may mean that a larger powerhead size is required to ensure proper forming.
4. Facility specifications- The environment in which the powerhead will operate is also critical. Orbitform's powerheads are designed to operate at a maximum of 100 psi but are typically run at 80 psi. If a lower air pressure is used, the force output of the equipment is also reduced. It is important to know what air pressure will be consistently supplied to the powerhead during manufacturing. If the force required to form the material is near the force capacity for a specific powerhead, but the air pressure supply will be lower than 100 or 80 psi, a larger powerhead may be required.
5. Multi-Riveting- One way to increase throughput and decrease costs for an assembly with multiple riveting locations is to form them simultaneously. Orbitform offers multi-spindle and multi-point forming heads to do just that. When forming multiple rivets at one time, however, the force output of the powerhead is distributed between each riveting location. If an assembly has three riveting locations, the force output of the machine would need to be three times that of the force required to form one of the rivets.
Again, these are just a few of the many factors to be considered when determining which size powerhead is required. There are many variables that can affect every assembly. As fastening and forming experts, Orbitform has partnered with many manufacturers to help assemble tens of thousands of different parts. We stand ready to support your next assembly application.
Contact us today to discuss your next project and let our lab technicians test your sample parts in our lab to determine what size powerhead best fits your requirements.