User Tips For Hydraulic Cylinders

Holmatro’s Top 10 Tips to ensure Safe, Reliable & Durable use of your Hydraulic Cylinders!

1. Vent your Hydraulic System before use

In contrast to oil, air in a hydraulic system is dangerous because air is compressible. It makes the operation of the cylinder plunger unpredictable. Always vent a hydraulic system before use by turning the pump upside down and pumping the cylinder empty, then allow the oil to flow back into the pump which must be higher than the cylinder. Venting the pump removes all air from the system.

2. When using a Double-Acting Cylinder, always connect both couplings (of the pump).

This allows a flow of incoming oil and a flow of outgoing oil. The principle underlying a double-acting or hydraulic-return cylinder is that the in and out strokes of the plunger are controlled by oil pressure. On the out stroke of the plunger, the incoming flow of oil passes through the lower coupling into the lower chamber of the cylinder housing, and this presses the plunger upward. Oil in the upper chamber must escape to make room for the incoming oil. This outgoing flow of oil passes through the upper coupling into the cylinder housing, back to the pump. The oil flow process is exactly the reverse of the in-stroke of the plunger. If the pump only has one coupling, it is not compatible with a double-acting cylinder.

3. Avoid damaging your system.

• Protect all parts of the hydraulic system from sparks when performing welding or grinding work to prevent leaks.
• Use a saddle to protect the plunger from becoming deformed. Deformed plungers can easily get stuck at the end of the return stroke. In addition, the cylinder will become eccentrically loaded because the damaged plunger surface can no longer fully supported that load.
• Never lift the cylinder using the coupling or hose. Always use the handle fitted for that purpose, the cylinder housing, or the
  hoisting eyes.
• Prevent damage to the hydraulic hose arising from kinks, knots and pinching, such damage can give rise to leaks.

4. Use Hydraulic Cylinder Accessories & Tools only as they are intended to be used.

• When attaching and removing accessories to the plunger, allow the plunger to go in and out completely using a pressure of about 50 bar. This prevents the plunger turning at the same time.
• Do not place a support on top of the plunger. If a support is used always place it underneath the cylinder. And always use original accessories that are completely compatible with the hydraulic system. This prevents unsafe situations, such as slippage or breaking of parts under pressure.
• Only connect an extension hose at the bottom of the cylinder itself, never on the plunger. A maximum of two extension hoses may be connected to a coupling unit. The surfaces between which the force is applied must be parallel, for example, at the heart of the base plate and the saddle.

5. Make sure the Hydraulic Cylinder is placed on a stable surface

So that it cannot roll away or tip over.

6. Apply force centrally on the Cylinder

Avoid lateral and oblique forces on the plunger to prevent internal damage within the cylinder housing. Use a tilting saddle for eccentric loads up to a maximum of 5°. Avoid eccentric loads of more than 5° on the cylinder.

7. Use more Cylinder Capacity than the load actually required

• Symmetric load = total cylinder capacity = 1.5 x load
• Asymmetric load = total cylinder capacity = 2 x load

8. Release pressure from your Hydraulic System

Always release the pressure from the system before you disconnect the hose or cylinder! This allows the
couplings to be unscrewed by hand and prevents residual pressure remaining in the system, which might have negative effects during subsequent use.

9. Keep your Hydraulic System clean

• Prevent dirt in and on the couplings. Screw the coupling dust caps to each other before using the system and clean them after.
• Painted, plastic and rubber parts are not resistant to corrosive acids or liquids. Use plenty of water to rinse off all parts that come into contact with strong acids or liquids, except for electrical components.
• Thoroughly dry off the cylinder after it has been used in wet conditions. Apply a thin layer of preservation oil on the white or black parts to prevent the formation of rust.
• When putting the cylinder into storage, lower the plunger to prevent dirt from entering the cylinder.

10. Carry out maintenance on the Hydraulic Cylinder regularly.

All brands of hydraulic tools can occasionally malfunction or become defective in the course of time. Regular maintenance is required, as well as an annual test (inspection) by an expert* to ensure that tools remain usable and safe for as long as possible.