Learn how to assemble a hydraulic cylinder with our instructions
Assembly of a hydraulic cylinder always begins with cleaning all cylinder components to ensure the finished unit is free from contaminants. A clean assembly is essential for reliable operation and long service life.
Below are the basic steps for assembling a cylinder.
Remember, seals must be installed on the piston and in the seal housing before the main assembly begins. For guidance on how to properly install the seals, refer to the seal installation instructions [here].
Hydraulic Cylinder Assembly Instructions
Assembly begins by securely fixing the rod in a press. Follow these steps carefully to avoid damage and ensure proper function:
1. Clean the rod surface with a non-abrasive cloth and cleaning agent (e.g., brake cleaner).
2. Lubricate the seals with oil after confirming they’re clean.
3. Slide the seal housing onto the rod, taking care to avoid sharp edges. If needed, smooth out any sharp corners at the base of the rod to prevent damage to the seals during installation.
4. Install the piston onto the rod and lubricate the seal surfaces. Threadlocker is often used on the piston—check what type is required.If the correct torque value is known, tighten the piston using a torque wrench or torque bench. Torque requirements increase with thread size. If the piston uses a locking screw, secure it and apply a small punch mark next to the screw head to prevent it from loosening and damaging the cylinder.
5. Remove the rod from the press and secure the cylinder tube in the bench.
6. Insert the rod, seal housing, and piston as a unit into the cylinder tube. Again, take care not to damage the piston or seals, and make sure the rod is clean.
7. Tighten the seal housing using a hook spanner, bolts, or a retaining ring—depending on the design.
8. Check for locking mechanisms in the guide and tighten them if present.
Final step: Let the cylinder sit for at least 30 minutes to allow threadlocker to cure before performing a function test.
