Hydraulic cylinders are expensive, and the last thing you want is your inventory deteriorating from incorrect storage. It’s vitally important to store your hydraulic cylinders correctly. Proper hydraulic cylinder storage will prevent internal and external damage to the cylinder.
Necessary Hydraulic Cylinder Treatment Before Storage
Grease
Smear the internal surfaces of the eye, clevis bushes and bearings with grease – particularly if they’re made of steel. This will protect all of the exposed metal parts from rusting.
Oil-Impregnated Tape
To preserve the cylinder rod’s chrome exposed areas, you can use oil-impregnated tape such as Denso tape to form a protective covering. Before applying the tape, make sure the rod is fully retracted. If the rod is not fully retracted first, the subsequent retraction of the rod can damage the rod seal.
Service Port Plugs
Plug the service ports with steel plugs that are rated for the cylinder’s working pressure. Plastic plugs don’t provide the same sealing integrity as metal plugs and are easily dislodged because of their smooth external diameter.
For safety, attach appropriate warning tags to both service ports. Fit each port blank with a pressure test point. This enables the quick attachment of a pressure gauge to check the pressure in the cylinder. This way the pressure can be safely vented into a drum using a test-gauge hose, and there will be no surprises when opening the ports.
Recommended Hydraulic Cylinder Storage Practices
Storage With Air
Make sure that the air used to fill the hydraulic cylinder is dry. If the air is laden with moisture, it can cause spot rusting and pitting of the tube surface, which will reduce the cylinder’s volumetric efficiency, the piston seal’s service life, and ultimately, the life of the tube itself.
It’s recommended that you store hydraulic cylinders filled with air in a vertical position with the piston rod facing upwards and the cylinder fully retracted. This will minimise static side loads on the seals and corrosion by preventing condensation. Vertical storage of heavy hydraulic cylinders comes with safety issues. If the cylinder falls, it could cause damage to the cylinder and possibly injure staff.
Storage With Oil
It’s recommended that the heavy, expensive and high-pressure hydraulic cylinders should be stored with oil. Filling a cylinder with oil is something you have to weigh up based on the cylinder’s value and how long you expect it to be in storage. When you fill the cylinder with oil, make sure it is fully retracted and use the rod-end port to fill the cylinder. This will eliminate the risk of damage that the intensified pressure could cause.
Due to safety reasons, it’s recommended that heavy hydraulic cylinders are stored horizontally. However, long periods of storage in this position for heavy cylinders will create a “sagging” effect on the seals. Rubber seals have a “creep” property that allows them to deform under a load. Long-term exposure to high levels of stress on the seals may result in the seals losing their elasticity. To avoid damaging the seals, rotate the hydraulic cylinders at 90-degree increments once every two weeks.
Hydraulic Cylinder Storage Conditions
Store your hydraulic cylinders indoors in a clean and dry area where the cylinders won’t be in direct sunlight, snow or exposed to any extreme changes in temperature. UV deterioration from sunlight causes the exposed surfaces of your hydraulic cylinders to discolour and crack. In extreme cases, there could be complete hydraulic cylinder disintegration if left out in the sunlight for too long.
If the hydraulic cylinder is stored filled with oil and is exposed to heat, the oil will expand. This will cause the internal pressure to exceed the working pressure, causing seal failure. This can be extremely dangerous to someone opening a port which is under pressure. Even if the pressure does not reach damaging levels, the cooldown will cause a vacuum which will contaminate the fluid with moisture-laden air which can cause corrosion down the line. That’s why it’s essential to make sure the storage area does not have climatic variations like exposure to extreme heat or cold.
Conclusion
If you prepare correctly and follow the safety precautions mentioned in this article, you will ensure the longevity of your hydraulic cylinders when you have to put them in storage. If you have suffered damage to your cylinders due to improper storage or any other incident, contact Kappa Engineering. We can repair or remanufacture any hydraulic cylinder.
Hydraulic Cylinders for sale from Kappa Engineering
If you need 250 Series hydraulic cylinders, 150 Series cylinders or Tipper Series cylinders, click here to order them from Kappa Engineering. We manufacture hydraulic cylinders with any mounting type or port position you require. We manufacture every component of the cylinder in-house and we design and build custom hydraulics for specialised applications.
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