Hydraulic Cylinder Piston Rod Manufacturing Process

The hydraulic cylinder piston rod is a connecting part that supports the piston to do work, as well as a moving part with frequent movement and high technical requirements. The quality of its processing directly affects the life and reliability of the hydraulic cylinder, which has high processing requirements and strict requirements on coaxiality and wear resistance. Today let’s learn more about the manufacturing process of it.

Three types of hydraulic cylinder piston rod.

  1. Solid piston rod.
  2. Hollow piston rod. It is assembled and welded by the rod head, shaft and rod end.
  3. Hollow piston rod with oil inlet tube. It is assembled and welded by the rod head, shaft, rod end and oil inlet tube.
solid hydraulic cylinder piston rod
hollow hydraulic cylinder piston rod
hollow hydraulic cylinder piston rod with oil inlet tube

Main manufacturing process of hydraulic cylinder piston rod.

1. Raw material preparation and workblank production.

  • Commonly used materials for piston rod are CK45, 4140, 5140, SS304, SS316, etc.
  • Determine the workblank margin according to the aspect ratio, the state of the workblank, etc.
  • Straightening.
  • Combined piston rod parts manufacturing.

2. Assembly and Welding.

  • Assemble according to the drawing.
  • Position welding, welding, and detect flaws as required, and then transfer to the next process after passing the test.

3. Heat treatment.

Piston rods are usually heat treated after rough machining and before finishing machining. Common heat treatment methods include normalizing, tempering to stress, quenching and tempering, etc., which are adopted according to design requirements.

4. Turning.

  • Workpiece clamping correction.
  • Turning support gear, drilling center hole, turning length.
  • Rough turning outer circle.
  • Semi-finished turning, refined turning outer circle.
  • Threading.

5. Processing other structural parts of the hydraulic cylinder piston rod.

6. Grinding before chrome plating.

  • Grinding before chrome plating.
  • Grinding size, precision and roughness before chrome plating should ensure economy, plating thickness, and proper polishing amount.
  • Checking the size of the outer circle, the roughness Ra0.4-0.6, and observing whether there are other defects.
Straightening Machine
Cylindrical Grinding Machine
Centerless Grinding Machine
Burnishing Machine

7. Chrome plating on the surface of hydraulic cylinder piston rod.

Chrome plating on the outer circle, and there must be no plating defects.

8. Grinding.

Grinding after chrome plating, and inspecting the dimensional accuracy, roughness, plating thickness, etc.

9. Patching.

During the flow of manufacturing process, the hydraulic cylinder piston rod is easy to get defected such as bumps, scratches, and surface cracks that do not affect the overall quality, but must be mended. According to the defect situation, argon arc welding or cold welding machine can be used for repair welding, fine filing to make the outer circle smooth, emery paper polishing or brush plating method for partial patching.



Leave a Comment

Your email address will not be published. Required fields are marked *