What are the tips for using hydraulic cylinders?

When we grasp the theoretical principles of hydraulic cylinders, we often assume we can handle any situation and encounter no difficulties in their operation. We feel confident tackling a wide range of issues, yet in practice, many challenges remain unresolved. So, what are the key tips for using hydraulic cylinders?

What are the tips for using hydraulic cylinders?

1. How to install and secure a hydraulic cylinder

There are two common methods for securing hydraulic cylinders:

1. The first type is a square hydraulic cylinder fixed to the B‑plate, which must be positioned on the B‑plate using a key.

2. The second type is a circular hydraulic cylinder mounted on the push plate. It should be noted that a locking screw for the ejector plate must be installed adjacent to the hydraulic cylinder. This location is subjected to significant forces, so it is essential to prevent deformation.

3. Additionally, it is necessary to engrave the hydraulic cylinder with its dimensions, shape, quantity, brand, and stroke length to facilitate inspection.

How should the connection between the hydraulic cylinder and the formwork be designed?

The hydraulic cylinder is connected to the circular T‑shaped block of the formwork, which is designed with a U‑shaped groove to facilitate fabrication and installation. The mating surface dimensions are 8–12 mm, with a clearance of 0.5 mm from other adjacent features. The hydraulic cylinder connector features an internal thread, available in two thread types. For the internal thread, the screw can be directly secured behind the T‑shaped block.

Note: The dimensions and thread pitch of the hydraulic cylinder’s new head shall be based on the 2D specifications provided by the hydraulic cylinder manufacturer. In particular, if the thread pitch is not specified, errors are likely to occur.

3. How should the hydraulic cylinder fittings be installed, and how should the air hoses be routed?

Hydraulic cylinder fittings come in two types: internal threads and external threads. Internal threads are directly threaded onto the back of the T‑block, while external threads require tapping.

That’s not the main point of the discussion. The T‑block is round, so it’s not easy to clamp. To tighten a screw, you need to cut two flat surfaces. I’ve never done any fitter’s work and often find myself longing for better design.

How do you stop the hydraulic cylinder from rotating?

Why does the hydraulic cylinder stop rotating? In this case, we can understand that the moving piston inside the hydraulic cylinder has not actually come to a halt; during repeated high-speed motion, it may begin to rotate, leading to loosening of fasteners and posing a safety hazard. Therefore, a design that prevents rotation becomes essential.

There are typically two design approaches:

1. Make a non-rotating washer.

2. Secure a headless screw.

Maintenance Tips for Hydraulic Cylinders

1. Keep the hydraulic oil clean. Contaminants in the oil can damage system components.

2. Maintain the hydraulic oil level. If the oil level drops, air will enter the system and cause abnormal operation.

3. Check the hydraulic cylinder for oil leaks. Oil leakage occurs when seals are damaged and not replaced promptly. This not only depletes engine oil but also reduces output; in severe cases, it can render the system inoperable.

4. Familiarize yourself with the normal operating sounds of the system and distinguish them from any abnormal or fault-related noises. If you detect an unusual sound, identify the issue promptly and address it to prevent minor problems from escalating into major ones and causing significant losses.

5. Be sure to check that all tightened components are secure and maintain their proper condition.

Hydraulic cylinders are widely used in mechanical equipment, but their O-rings are prone to damage. When an O-ring wears out, the gap between the rod side and the non‑rod side of the cylinder widens and becomes interconnected, effectively interrupting the return oil circuit on the rod side. In fact, due to this inter‑chamber leakage, pressurized fluid from the rod chamber frequently flows from the high‑pressure zone to the low‑pressure zone. Once this flow occurs, the piston loses its equilibrium and moves toward the rod chamber in search of a new balance. With each reciprocating stroke, the piston continues to shift until it is stopped by an external force. This phenomenon significantly affects the operation of the hydraulic system. Replacing the cylinder piston’s O-ring can remedy unstable cylinder performance and substantially extend the service life of the hydraulic cylinder.