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Regarding the storage of hydraulic cylinders, most people’s storage methods are not standard. Today I will introduce to you the storage method of hydraulic cylinders.
01. Long-term storage
When storing hydraulic cylinders, we must first distinguish between short-term storage and long-term storage. Short-term storage refers to idleness within three months, and all other situations are considered long-term storage.
In practical applications, rust on hydraulic cylinders is a relatively common problem. Rust has adverse consequences on hydraulic transmission systems and their components, and may even paralyze the entire system. Therefore, it is crucial to do a good job of rust prevention on hydraulic cylinders. When our hydraulic cylinders are idle for more than 3 months, we must use the correct method to prevent the hydraulic cylinders from rusting. It is recommended that you follow the following methods:
1.Cleaning: Drain the waste oil in the hydraulic cylinder, clean it with diesel or kerosene, and then wipe the cylinder with a clean cloth.
2. Add anti-rust medium: Add protective oil inside the hydraulic cylinder and on both sides of the piston to prevent corrosion inside the cylinder. The protective oil must be compatible with the seals used and the working medium of the hydraulic system.
You can use mixed anti-rust oil to fill 80% of the cylinder volume, or fill the cylinder with 100% hydraulic oil. As a minimum requirement, the cleanliness of the medium must meet level 8 of the NAS 1638 standard, and the cylinder needs to rotate half a turn every 2 months.
3. Parts protection: Unprotected parts, such as the exposed part of the piston rod, need to be protected with special grease; bearings are protected with sealing tape and then covered with furnace packaging to prevent moisture and rust.
4.Wrap the entire oil cylinder with oil paper or stretch film and place it on a raised place. Do not let it touch the ground directly. It is best to store it in a wooden box.
02. Short-term storage
After the factory test, 10% of mixed anti-rust oil is generally added to the cylinder body of the hydraulic cylinder. Therefore, for short-term storage of no more than three months, no special measures can be taken.
Storage is also a way to maintain equipment. Everyone should learn the correct storage method of hydraulic cylinders. For cylinders that have been purchased and temporarily unused during holiday, you can refer to the following storage methods:
1. Store in a dry, clean, well-ventilated and no corrosive gas environment;
2. Place the hydraulic cylinder vertically with the piston rod facing up. This can prevent corrosion caused by condensation inside the hydraulic cylinder and reduce the probability of deformation of the seal due to the deadweight of the piston and piston rod. At the same time, it can save storage space.
3.Keep the protective cover on the oil port until the pipeline is connected.
03. Hydraulic cylinder installed on the equipment
For hydraulic cylinders that have been installed on machines and used, if they are not used for a short period of time, the piston rod must be completely retracted back into the hydraulic cylinder and must not be left exposed to the air to avoid corrosion and rust.
04. Inspection before use
1. Long-term storage of hydraulic cylinders
If the storage time of the hydraulic cylinder is more than one year, or the actual storage conditions cannot meet the above requirements, a comprehensive inspection must be carried out before the hydraulic cylinder is put back into use, and its usability must be confirmed by (functional tests). These functional tests include:
1) Increase the pressure for 10 minutes to check whether there is oil leakage inside and outside;
2) Inward and outward movement of the hydraulic cylinder.
2. Hydraulic cylinders stored for a short period of time
For hydraulic cylinders that are idle for a short period of time, there is no need to verify the availability before use. The following checks can be performed:
1) Check whether the threads, bolts, etc. connecting parts are loose;
2) Check the sealing performance of the cylinder, especially whether there is leakage at the joint between the piston rod and the cylinder head;
3) Perform a full extension and full retraction test run for 5 strokes, and then run under load. This can exhaust the air in the system, preheat the systems, and effectively avoid the presence of air or water in the system.
3. Hydraulic cylinders that have been suspended from use
For hydraulic cylinders that have been installed on mechanical equipment and have been suspended from use, add lubricating oil to the swing shaft, hinge point, pin shaft, etc. before reusing them after the holiday.