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1. The purpose of the equipment is the workpiece condition.

2. Structural characteristics, load conditions, required speed, size stroke and action requirements of the working mechanism.

3. The selected hydraulic system working pressure.

4. Current status of materials, accessories and processing technology.

5. Relevant national standards and technical specifications.

6. The piston rod should be subjected to a large load in the multi-tension state as much as possible, and has good longitudinal stability under multi-pressure conditions.