How to change the sealing ring of the single acting sleeve hydraulic cylinder

The sealing ring of the hydraulic press is in the hydraulic system, and its main role is to prevent the leakage of lubricating oil and the entry of foreign objects from the outside world. It is an annular cover composed of one or several parts, fixed to one ring or washer of the bearing, and in contact with another ring or washer or to form a very tight gap. There are many types of it, but basically they are made of nitrile rubber, natural rubber, ethylene propylene rubber, silicone rubber and other materials.

As we all know, the precision firmware of the hydraulic press is often damaged and malfunctioned, and once damaged, it can only be replaced. Tengzhou Kexin Company according to the knowledge accumulated in the actual work, explain how to correctly replace the sealing ring of the hydraulic press

1.First of all, the cylinder rod of the upper mold and the hydraulic cylinder is disassembled, so that the upper mold is separated from the cylinder rod of the hydraulic cylinder. (The upper mold needs to be padded).

2.It is best not to replace the sealing ring of the hydraulic cylinder in the workshop, and the hydraulic cylinder should be removed as a whole and placed in a clean and dust-free site. (The pressure must be relieved before dismantling, and if the cylinder rod of the hydraulic cylinder is placed in the highest position, there should be corresponding measures to prevent the cylinder rod from falling after the pressure is relieved).

3.Remove the rear end cover of the hydraulic cylinder, pull out the piston and piston rod, remove the front end cover, and the sealing ring of the hydraulic cylinder can be fully seen (note: some hydraulic cylinders only have the front end cover, and the principle is not much different).

Carefully inspect the seals in the following locations: piston rod seals, piston seals, end cap seals, buffer device seals, exhaust valve seals, etc., find the damaged seals, and select the correct seal to replace.

4.There are many types of sealing rings, and there are basically these kinds of commonly used ones: Y-rings, YX-rings, V-rings, grid seals, sterseals, and some combination seals, as well as some guide rings and dust rings used with seals.

According to the size of the sealing groove of the hydraulic cylinder, the seal with the same specification as the original seal is selected and replaced correctly. If you are not familiar with it, it is best to find a professional person to do it, (some seals need to be hot-charged), and after installation, you should also use pressure equipment to conduct pressure resistance tests, which is very important!

5. Install it in the order of removing the hydraulic cylinder, and pay attention to the details.

First remove the cylinder head of the front end of the cylinder, the cylinder head is not easy to remove, first use a hammer and felt to loosen the thread, and then the pipe wrench unscrews the end cover, take out (spring) and piston rod, replace the seal, if there is no special tool when replacing the seal, you can boil water to scald the seal for easy installation, and replace the seal and dustproof seal at the front end of the piston rod at the same time.

The decomposition steps of the telescopic sleeve hydraulic cylinder for the single work to make an alarm are as follows: remove the hydraulic cylinder: remove the hydraulic cylinder from the mechanical equipment and place it on the working bending platform.

Removing the piston rod: Removing the piston rod from a hydraulic cylinder usually requires the use of a wrench or nut cutter. Remove the piston head:

Use a wrench or nut cutter to remove the head of the hydraulic cylinder, which is usually held in place by a nut or bolt. Remove the sleeve: Remove the sleeve of the hydraulic cylinder from the base of the hydraulic cylinder.

If the sleeve and base are fastened in a threaded way, it needs to be removed with a wrench or wrench barrel; In the case of keyway method, the sleeve needs to be detached with a crowbar or tool. Remove the seal and piston: Remove the seal and piston in the hydraulic cylinder sleeve, and pay attention to check whether the seal is worn or aged.

Cleaning parts: Clean all parts of the hydraulic cylinder with detergent, and wipe the surface of some parts. Check the parts:

Check the wear of each component of the hydraulic cylinder and replace the worn parts if necessary. Assembly: Assemble the hydraulic cylinders in reverse order, assembling components such as pistons, seals, sleeves and piston rods into the cylinders.

Pay attention to apply lubricating oil or hydraulic oil during the assembly process to ensure the normal operation of the hydraulic cylinder.

Installation steps: When the piston is assembled with a U-shaped sealing ring, a clamp is required, that is, a cone, the diameter of the big head is about larger than the diameter of the end of the piston sealing groove, the cylinder of the big head with a little length is too good, the sharp corners must be rounded, and the roughness must be less than.

The piston and the clamp are installed concentrically, the clamp is coated with butter, the sealing ring is heated to 55 degrees in the oil, then the oil is applied, and the piston sealing groove is pushed along the clamp.

The guide sleeve hole is equipped with a sealing ring Peiyu key, and the sealing ring is coated with butter in the inner hole, and the sealing ring is also heated to 55 degrees in the oil, and then coated with butter, and squeezed into the sealing groove in the guide sleeve hole by hand.

Seal ring introduction: It is a kind of accessories used for sealing, mainly including V-shaped sealing ring, U-ring, O-shaped sealing ring, rectangular sealing ring, Y-shaped sealing ring dismantling, Yx-type sealing ring for holes, YX-type retaining ring for holes, YX-type retaining rings for shafts, YX-type sealing rings for shafts, etc. It is widely used in the sealing of hydraulic cylinders in construction machinery.

Installation steps: When the piston is assembled with a U-shaped sealing ring, a clamp is required, that is, a cone, the diameter of the large head is about greater than the diameter of the end of the piston sealing groove, the cylinder of the large head with a little length is too good, the sharp corners must be rounded, and the roughness must be less than.

The piston and the clamp are installed, the clamp rising bucket is greased, the sealing ring is heated to 55 degrees in the oil, and then the oil is applied and pushed into the piston sealing groove along the fixture.

The guide sleeve hole is equipped with a sealing ring, and the inner hole is coated with butter, and the sealing ring is also heated to 55 degrees in the oil, and then coated with butter, and squeezed into the sealing groove in the guide sleeve hole by hand.

Seal ring introduction: It is a kind of accessories used for sealing, mainly including V-shaped sealing ring, U-ring, O-shaped sealing ring, rectangular sealing ring, Y-shaped sealing ring, Y-shaped sealing ring for hole, YX-type retaining ring for hole, YX-type retaining ring for shaft, YX-type sealing ring for shaft, etc. It is widely used in the sealing of hydraulic cylinders in construction machinery.

It is installed on the piston, and its main function is to seal the gap between the piston and the cylinder barrel to prevent the leakage of hydraulic oil. The piston seal is the main seal in the hydraulic cylinder, which bears pressure in both directions and is one of the most important seals for the pressure value that the hydraulic cylinder can bear. The main requirements for piston sealing are good sealing effect, good pressure holding effect in static state, strong pressure bearing capacity during movement, anti-extrusion, small friction coefficient, long service life, etc.

There are various forms of piston seals, and the most suitable form can be selected according to different use environments.