Devices
| As their name indicates, “positioning cylinders” are the hydraulic workholding components |
used to move the part into place against the reference planes. Chapter 2 explains and illustrates single- and double-acting versions and the three mounting styles: threaded, manifold, and flanged. Hydraulic connections to threaded cylinders are via tubing. Flanged cylinders may be fed via tubing or manifold, and manifold cylinders are designed for manifold supply. Enerpac’s Collet-Lok locking cylinders for positioning are detailed in Chapter 4.
|
|
|
Piston end-attachments, called “end effectors” or “contact bolts, “ protect the piston and the part during the pushing operation. Mounting versatility is provided by a selection of mounting blocks, also referred to as mounting brackets. Flange nuts, also known as jam nuts, secure threaded cylinders in place. |
Cylinder Selection
Selection of a positioning cylinder is dependent on several factors:
- The cylinder must overcome the weight of the part and friction between part and fixture. Whether weight or friction predominates depends on whether the machining center is vertical or horizontal. Additionally, support and locating elements may add friction.
- Product literature provides maximum rated force for each cylinder offered. Selection is then narrowed by examining force vs. hydraulic pressure data for each cylinder.
- Bigger is not necessarily better. Oversize cylinders may damage parts, and they create crowding on the fixture.
- When selecting cylinder stroke length, observe the 80% rule: the actual stroke in the application should not exceed 80% of the cylinder’s maximum stroke.
|
 |
 |
|
 |
|
 |
TM and © Enerpac 2011
All rights reserved. Reproduction of any materials without Enerpac’s permission is strictly prohibited. |
|
