Enerpac WST-72 - Manual (Page 6)

DESCRIPTION
Fluid Advanced
Hydraulic oil enters the port and raises the piston. The plunger raises by spring force
until it contacts the workpiece. Once the plunger meets resistance, hydraulic pressure
increases and exerts force on the plunger sleeve. The sleeve compresses and grips the
plunger locking it in position.
When hydraulic pressure is released, the sleeve expands and the plunger is retracted by a
spring.
Spring Advanced
The weight and contour of the workpiece automatically positions the plunger height.
Hydraulic oil enters one port and compresses the sleeve, gripping the plunger and
locking it into position.
When hydraulic pressure is released, the sleeve expands, releasing the plunger.
INSTALLATION
1. Place the work support at the lowest point of the hydraulic system to aid in venting.
If that is not possible, provide a bleeder plug at the highest point of the system.
2. Install the work supports by threading in the fixtures. The work support should be
mounted so that the plunger is at the approximate middle of its stroke when
contacting the workpiece in the fixture. Torque to 11-15 ft-lbs. (15,0 – 20,0 Nm).
3. Remove one shipping plug and connect the hydraulic line using appropriate fittings
(WFT 71, WFT 72, WST 71, WST 72 only). All hoses and fittings must be rated at
5,000 psi (350 bar) minimum.
4. If multiple supports are connected, they should be connected in a series using both
hydraulic ports (WFT 71, WFT 72, WST 71, WST 72 only). The ports function the
same and either can be used as the input port.
5. The hydraulic power pump must be capable of producing 5,000 psi (350 bar). For
most applications, 3,000 – 4,000 psi (207 – 276 bar) will be required. For heavy
workpieces, 5,000 psi (350 bar) may be needed. Power pumps must be large enough
to provide a usable oil supply for the work supports, hoses, clamps, and all other
items in the system. Refer to table 1 for maximum holding forces vs. operating
pressure.
OPERATION
1. For the WST71, WST72, WSM 71, and WSM72, the weight and contour of the
workpiece automatically positions the work support plunger height. For the WFT71,
WFT72, WFM 71, and WFM72, the plunger is raised by hydraulic pressure until it
contacts the workpiece.
2. Activate hydraulic pressure to advance the plunger against the workpiece (WFT 71,
WFT 72, WFM 71, WFM 72 only). Work support plunger position will be
maintained until hydraulic pressure is released.
3. Clamp the workpiece in position to facilitate machining operations.
4. When machining is complete, release the clamps and then release the hydraulic
pressure to the work supports by closing system valves or turning off the power
pump.
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