Application · Press & forming duty
A press power unit is a working machine, not a holding one. It has to drive a ram through a forming stroke — high force from high pressure, real speed from high flow — then hold, decompress and retract, cycle after cycle. That means higher working pressure (up to about 650 bar), more flow, a larger tank and cooling, and control features a clamping power pack never needs. Suyog engineers each press HPU around the press tonnage, stroke and cycle, and tests it up to 650 bar before it leaves the works.
Where a clamp closes and holds, a press works — it converts hydraulic energy into a forming stroke on every cycle. That single difference drives everything about the power unit: pressure, flow, tank, cooling and control all scale up.
The two applications share components but sit at opposite ends of the map. This contrast is the quickest way to see why a press unit is built the way it is — and why a clamping pack cannot simply be scaled up.
| Aspect | Clamping duty | Press / forming duty |
|---|---|---|
| Nature of duty | Hold a set force steady | Drive a forming stroke, then hold & retract |
| Working pressure (typical) | 40–200 bar | Up to ~650 bar |
| Flow (typical) | Low — only to close the clamp | High — for ram approach and stroke speed |
| Reservoir & cooling | Small, often no cooler | Larger tank; cooler common on continuous duty |
| Key control features | Load holding, pressure switch | Load holding, decompression, two-stage flow |
| Motor size | Modest | Larger — sized to peak pressure × flow |
Ranges are typical and illustrative of press forming duty. Suyog specifies and tests each unit to the requirement agreed from your press data — up to 650 bar / 200 LPM in-house.
Press and forming duty is usually a custom or engineered build. These are the natural starting points — send the press tonnage, stroke and cycle and we will engineer the unit around them.
Purpose-built HPUs for press and forming duty, up to 650 bar / 200 LPM.
View product →Complete press hydraulic systems — power unit, controls and actuation.
View product →Integrated manifolds for directional, relief, decompression and load-holding logic.
View product →Sizing a press unit means getting pressure, flow, motor and tank all right. These guides carry the method, and the calculators do the numbers.
The full application-to-unit method, step by step, with a worked example.
Read guide →Why pressure sets tonnage and flow sets ram speed — independently.
Read guide →Turning high pressure and flow into the right motor kW for the peak.
Read guide →Why a press needs a larger tank — and when to add cooling.
Read guide →Free pressure, flow, motor-power and tank calculators.
Open calculators →Press and forming duty runs high — commonly up to about 650 bar, which is the top of Suyog's in-house build and test capability. The working pressure follows from the press tonnage and the ram cylinder bore: higher pressure on a given bore makes more force. Clamping typically sits at 40–200 bar, so a press unit is specified well above that. These figures are typical and illustrative; the working pressure is set from your press data.
Flow sets speed, and a press ram has a real stroke to cover on every cycle, so it needs far more flow than a clamp that only nudges shut. Many presses use a two-stage approach — high flow for a fast approach, then reduced flow at high pressure for the pressing stroke — often with a variable-displacement pump or an accumulator so the motor is not sized for the peak of both at once.
Higher pressure and flow put far more energy through the oil, and pressing, holding and throttling all turn pressure straight into heat. A press unit therefore uses a larger reservoir — often toward the upper end of the 3–5× flow rule or beyond — plus an air or water cooler to hold oil below roughly 55–60 °C on continuous duty. An undersized tank and no cooling is the fastest route to a press that overheats in service.
At the bottom of a pressing stroke the oil and frame store a large amount of energy under high pressure. Releasing it instantly makes a violent shock — the bang and pipe hammer familiar on big presses. A decompression circuit bleeds that pressure down in a controlled way before the ram retracts, protecting valves, pipework and seals and making the machine quieter and longer-lived. Load-holding valves keep the ram safely in place under load.
Related applications
Fixture and workholding duty instead? See Hydraulic Clamping Power Packs. Or browse every duty on the Applications hub.
Press duty, engineered & tested
Use the configurator to start a build, or send your press requirement and our engineers will specify the unit and test it up to 650 bar before it ships.
