What Ram Speeds Do You Need?
Hydraulic presses are frequently offered with multiple ram speeds such as; Fast Approach, Pressing and Fast Retract. Typically, these speeds are expressed in Inches Per Minute (IPM).
- Fast Approach Speed is designed to lower the ram quickly during the “travel” portion of the stroke that does not require any force
- Pressing Speed is commonly referred to as the “working portion” of the stroke where force is required and speed typically needs to be slower
- Fast Retract Speed or “Stripping Force” refers to the ram travel after the pressing portion of the stroke is completed, the ram retracts with little force
Many customers with mechanical press experience refer to press speed in cycles per minute or strokes per minute (SPM). Hydraulic presses can be designed to provide a certain number of cycles per minute once a cycle profile has been determined.
The cycle profile consists of an accurate description of the physical aspects of the cycle, which include:
- Distance of ram travel under no load (Fast Approach)
- Distance of actual working stroke (Pressing)
- Distance of Fast Retract (usually the combination of the previous two distances)
- Any Dwell Time at the bottom of the stroke or while under pressure
Once these parameters are established, the appropriate ram speeds can be developed in conjunction with the right cylinder configuration and power system in order to provide the necessary cycles per minute.
Variable ram speeds are also available through the use of flow controls, variable volume pump systems and SSD/VFD drives.