Orbitform's New Spin on Roller Forming
Permanent Assembly for Large Cylindrical Parts
Posted on 11/27/2013 | by The Orbitform Blog Team
If you are struggling to permanently assemble tubular or large diameter parts, Orbitform’s Roller Forming process may be the solution. Roller Forming is a non-impact process using a spinning Roller-head with two or more rollers to apply a 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. Assembly applications include: water pumps, bearings, ball joints, air bag canisters, electrical sensors, fuses, solenoids, and parts where a groove or lip is needed, such as sealing the end of a tube. An automotive part supplier wanted to reduce the cost and weight of their water pump by converting its cast iron housing to cast aluminum. Originally the bearing was press-fit into the housing. The result was lighter, but thermal expansion was greater. Repeated heating and cooling caused the bearing to walk-out. The customer tried adhesives to retain the bearing, but this added an addition expense and an additional process that was messy.
ORBITFORM ENGINEERS A SOLUTION
Orbitform’s Applications Engineers worked with the customer to design a retaining feature that could be formed using Orbitform’s Roller Forming process to permanently retain the bearing. A custom static two-roller tooling head was developed and tested using Orbitform’s standard Powerhead. For this application our engineers determined a rotational speed of 400 rpm was optimal when combined with the downward force of the Powerhead. The customer verified the result using a push-out test, which caused the cast aluminum housing to fail without pushing the bearing past the formed retaining lip. A custom designed fixture held the housing assembly, and a thru-spindle pressure pad held the bearing in place. Process monitoring included bearing presence confirmation, a load cell to monitor force, and LVDT to monitor the Powerhead’s stroke position. Three interchangeable Roller-Heads allowed the customer to use the same machine for three different water-pump assemblies. Safety equipment included a light curtain, guarding, and opto-touch activation buttons. As a general rule, 90% of Roller Forming applications are between 3/8” and 6” in diameter. Wall thickness can vary from 1/32” to over 1/4" depending on the type of material. The Roller-Head RPM and advance rate are controlled by Orbitform’s standard Powerhead to precisely form the material. The Powerhead can also be configured with an integrated Load Cell and LVDT for process monitoring and control, along with a thru-spindle pressure pad for part clamping during the forming process. For static Roller-Heads, typical cycle times range from 3-5 seconds depending on the application. Orbitform is your source for Assembly Equipment Solutions for Manufacturing. To learn more about anything talked about in this article, click here to visit our website, or call 800.957.4838 today to speak to the assembly experts.