Enerpac workholding hollow plunger hydraulic cylinders are designed for clamping, pushing, pulling, tensioning, pressing, and positioning applications where a rod, bolt, cable, tooling component, or other fixture element needs to pass through the center of the cylinder.
The hollow-plunger design provides additional flexibility when integrating hydraulic force into manufacturing fixtures and production equipment. This collection includes Enerpac CY, HCS, MRH, QDH, and RWH Series workholding cylinders in a range of capacities, strokes, mounting arrangements, and center-hole sizes.
Enerpac Workholding Hollow Plunger Cylinder Series
- CY Series Cylinders: Compact hollow-plunger workholding cylinders designed for integration into fixtures and production equipment. CY Series models can be used where a center opening is required for tooling, rods, or other fixture components.
- HCS Series Cylinders: Hollow-plunger hydraulic cylinders designed to provide substantial force from a compact workholding cylinder package.
- MRH Series Cylinders: Compact hollow-plunger workholding cylinders for applications requiring hydraulic force around a central rod, fastener, or fixture component.
- QDH Series Cylinders: Hollow-plunger cylinder designs for specialized workholding and fixture applications where compact installation and through-hole access are required.
- RWH Series Cylinders: Hollow-plunger workholding cylinders available in multiple capacities and strokes for pushing, pulling, clamping, and positioning applications.
Why Use a Hollow Plunger Cylinder for Workholding?
A conventional hydraulic cylinder applies force from the end of its plunger. A hollow-plunger cylinder adds a center opening through the cylinder, allowing a rod, bolt, cable, tooling element, or fixture component to pass through the cylinder while hydraulic force is applied around it.
This configuration can be particularly useful in machining fixtures, assembly equipment, pressing operations, punching applications, tensioning systems, and other production processes where force needs to be applied along the same axis as another component.
Depending on the fixture design, the load can be connected through the center of the cylinder to create either pushing or pulling action. This can provide a compact alternative to larger external cylinder arrangements.
Choosing a Workholding Hollow Plunger Cylinder
Start with the force and stroke required by the application, then determine the minimum center-hole diameter needed for the rod, bolt, cable, or tooling that will pass through the cylinder.
Also compare the cylinder's overall dimensions, mounting method, operating pressure, hydraulic connections, and available installation space. Because workholding cylinders are frequently incorporated directly into fixtures or machinery, physical dimensions and mounting requirements can be just as important as cylinder capacity.
For applications that do not require a center opening, browse our Enerpac Threaded Body Hydraulic Cylinders or Enerpac Block & Manifold Hydraulic Cylinders. You can also return to our Enerpac Hydraulic Workholding Cylinders collection to compare all workholding cylinder configurations.
