Clamps are used in fixtures for processes such as welding, adhesive bonding, pressing, riveting and leak testing. In material handling applications, clamps are used to grip parts in overhead transfer systems or to stop parts traveling on conveyors. Clamps can even be used like presses to install small parts, such as plugs.
Clamps can be powered manually, pneumatically or hydraulically, says Dave Doberstein, senior designer at Aladco (Waukesha, WI). Hydraulic clamps produce greater force than pneumatic ones. They are also more stable and move more smoothly. On the other hand, pneumatic clamps are faster, cleaner and more economical. Either way, a check valve should be installed with the cylinder to maintain clamping force if pressure is lost.