The Clevis

The clevis serves as a mounting system for hydraulic cylinders. It is a pivot mount, allowing the hydraulic cylinder to pivot along a single axis.

The Automotive Lift Repair Tampa Florida cylinder cap is where mounting options, such as the clevis, are attached. This widely used system is common in applications requiring the cylinder to pivot through an arc when extending and retracting, such as in mobile industrial or construction hydraulics like excavator booms. Clevis mounts are typically found in short-stroke hydraulic cylinders with small to medium bores.

To create a pivoting joint assembly, mounting brackets are fitted into the ends of the hydraulic cylinder, inserted into the clevis mount, and secured with a steel pin, cotter pins, or snap rings. Although clevis mounts provide a centerline mounting advantage, they may face side-load issues due to their limited range of motion. To mitigate this, spherical bearings can be used to accommodate slight misalignments, enhancing the hydraulic cylinder’s lifespan and preventing premature failure.

Other mounting options for hydraulic cylinders include:

  • Flange Mount: A flat plate that secures the hydraulic cylinder off its head, providing significant strength and stability without joints or bearings.
  • Trunnion Mount: A cylindrical extension that serves as a pivot point, similar to the mounts used for cannons on wooden battleships.
  • Lug Mount: A fixed mounting style with rectangular tabs welded or machined onto the hydraulic cylinder’s head and cap, offering strength and stability but prone to misalignment issues like other fixed mounts.

The End Cap

The Automotive Lift Repair Tampa Florida end cap seals the pressure chamber on one end of the hydraulic cylinder. Also known as the cylinder head or “blind end,” it is located inside the cylinder barrel, protecting it from sunlight exposure.

End caps are attached to the hydraulic cylinder’s body via bolts, rods, or threading. They can feature either a seal gland or an integrated rod sealing arrangement.

The Port

Automotive Lift Repair Tampa Florida Ports (or multiple ports in double-acting cylinders) are where hydraulic fluid enters and exits the system. In double-acting cylinders, ports are positioned at both ends, with the piston situated between them.

It’s crucial for ports to be robust, as any weakness could lead to dangerous leaks of pressurized hydraulic fluid. When addressing hydraulic cylinder leaks, inspecting this area is vital.

The Piston

Located inside the hydraulic cylinder, the piston separates the pressure zones within the cylinder barrel. The Automotive Lift Repair Tampa Florida piston’s back-and-forth motion generates power.

The piston rod connects to the piston using threads, nuts, and bolts to transfer linear motion. Pistons can rest in two positions: “sprung in” (retracted) or “sprung out” (extended). Understanding the resting state of the pistons in your hydraulic system is essential, especially in case of power loss.

The application of pressure affects different areas of the hydraulic cylinder; for example, pressure applied to the end cap causes the cylinder rod to extend.

The Rod

Also referred to as the piston rod, this component is critical for a hydraulic cylinder’s operation. The rod extends and retracts to produce movement.

It connects the piston and the cylinder head, linking the hydraulic cylinder to the machine performing the work, whether through a mounting attachment or machine thread. Proper polishing and finishing of piston rods are essential to prevent leakage, and this should be performed by a qualified hydraulic repair facility.

The Barrel

The hydraulic cylinder barrel contains the pressurized fluid and houses the Automotive Lift Repair Tampa Florida piston. The barrel must be constructed from durable materials to withstand the pressure and stress it endures.

Different types of steel are used for hydraulic cylinder barrels, each with varying degrees of strength depending on the specific application.

The Gland

Also known as the hydraulic cylinder gland or “seal gland,” this component houses several seals designed to prevent pressurized fluid from leaking past the piston rod or the connection at the cylinder head. These seals are crucial to avoiding misalignment and damage within the cylinder.

As noted, the end cap may either feature a seal gland or an integrated rod sealing arrangement. A seal gland simplifies the removal and replacement of all seals in the hydraulic cylinder.

The seals within the gland include:

  • Primary seal
  • Secondary seal
  • Wear bands
  • Wiper
  • Crapper
  • Static seal

The Seal

Seals are located throughout the hydraulic cylinder and are made from various materials depending on the application to prevent leakage. They are designed to withstand the repetitive movement of the piston rod within the cylinder barrel.

Automotive Lift Repair Tampa Florida Engineers select seals based on the hydraulic cylinder’s specific requirements. For example, seals resistant to melting are used in high-temperature applications, while polyurethane seals are preferred in low temperatures due to their resistance to cracking.

For hydraulic cylinders operating in environments with high friction (e.g., factories), seals made of Zurcon and PTFE are commonly utilized. Specialized seals may also feature backup rings for high-pressure applications or tight closures to prevent leakage of hydraulic fluids.

If a hydraulic cylinder is leaking, damaged seals may be a primary contributor to the issue.

Assembling Hydraulic Cylinders

Assembling a hydraulic cylinder is generally a straightforward process, with each part fitting together in a specific sequence. Assembly can only commence after all components have been inspected for quality and cleanliness.

Here are the basic steps for assembling an Automotive Lift Repair Tampa Florida hydraulic cylinder:

  • Begin by placing the seals (for the piston, cylinder head, etc.) in their designated positions along with the bearing and snap ring.
  • Attach the cylinder head and piston to the cylinder rod.
  • Oil the seals around the cylinder head and piston.
  • With the piston rod assembled, prepare for tube installation.
  • Horizontally fit the tube onto an installation bench, installing a bearing while carefully oiling the inside of the tube.
  • Insert the piston rod into the tube, piston end first.
  • Finally, install the grease nipples and bearings.

Throughout the assembly process, maintaining the cleanliness of the parts is a top priority. Avoiding contamination is essential for hydraulic cylinder maintenance, so surfaces should be kept clean and wiped as necessary. Regardless of the cylinder type, the assembly process generally remains consistent.

Different hydraulic cylinders may have varying assembly times; simpler single-acting cylinders typically require less time to assemble compared to more complex double-acting cylinders.