How to Clean a Hydraulic Cylinder?

How to Clean a Hydraulic Cylinder?

How to Clean a Hydraulic Cylinder?

Why Should a Hydraulic Cylinder Be Cleaned?

1. Protecting Felt and Sealing Elements

• Chips, dirt or rust particles remaining on the inner surface of the cylinder scratch the felts.
• This leads to premature loss of tightness and oil leaks.

2. Prevent Oil Pollution

• When an uncleaned cylinder is installed in the system, the particles in it mix with the hydraulic oil.
• Dirty oil  deteriorates valves, pumps and other sensitive elements in a short time.

3. Prolong Working Life

• Less wear → smooth lubrication → clean cylinder.
• This extends the life of the cylinder and the system and reduces maintenance costs.

4. Prevent Loss of Performance

• Dirt and rust inside cause the piston rod to strain and disrupt the flow.
• This reduces the power and speed performance of the cylinder.

5. Prevent Corrosion

• If moisture or foreign matter is not removed, corrosion begins on the inner surface.
• This can lead to irreparable deterioration of the cylinder barrel.

6. In terms of security

• Hydraulic systems operate at high pressure (100–300 bar or even higher).
• An uncleaned cylinder burst or oil leakage can cause serious work accidents.

Cleaning of hydraulic cylinders; It is  imperative for sealing, oil cleanliness, longevity, performance and safety.

1. Exterior Surface Cleaning

• The outer surface of the cylinder; It is cleaned of grease, dirt and dust.
• A clean cloth + solvent-based cleaner (e.g. industrial degreaser) is used for this.
• It  is dried with compressed air.
• This step is very important to prevent dirt from entering the interior.

2. Inner Surface Cleaning (Pipe Inner Diameter)

• The inner surface of the hydraulic cylinder tube (barrel) should be cleaned if it contains scratches, rust or particles.
• Methods used:
• Honing Process → Removes scratches, makes the surface smooth.
• Clean oil + flushing method → Drags out the sawdust, particles and dirt inside.
• Wiping with cloth and solvent (in small cylinders).

Note: The inner surface should not be left dry. After cleaning, a thin oil film must be applied.

3. Piston Rod Cleaning

• If there is oil, dust or rust on the piston rod, it  is cleaned with a soft cloth and solvent.
• Never  use sandpaper or wire brushes (the chrome plating will be damaged → the seals will wear out).

4. Sealing Elements (Seals, O-rings)

• The surfaces are cleaned before the seals are removed.
• Old seals are discarded, new ones  are installed clean and lubricated.
• No contaminants should come into contact during installation.

5. Cleaning After Assembly

• After the cylinder is closed, some filtered hydraulic oil is added to it  and it is moved back and forth several times by hand.
• Thus, the remaining particles are expelled.
• The cylinder  must be mounted on flushed lines before being connected  to the system.

Summary:
Hydraulic cylinder cleaning; It includes exterior wipe,  pipe inner surface honing or flushing, piston rod cleaning, seal renewal and lubrication steps. Purpose; to prevent damage to the seals, contamination of the oil and premature failures.

Hydraulic Cylinder Cleaning Procedure – Checklist

1. Preparation

• The cylinder is disengaged.
• The work area has been made clean and dust-free.
• Appropriate personal protective equipment (gloves, goggles, etc.) was worn.
• Materials are ready: clean cloth, solvent/degreaser, compressed air, filtered hydraulic oil, new seals/O-rings.

2. Exterior Surface Cleaning

• The outer surface of the cylinder was wiped with solvent and cloth.
• Oil and dirt are completely removed.
• Drying was done with compressed air.

3. Inner Surface (Cylinder Tube) Cleaning

• The inner surface of the cylinder tube was visually inspected (are there any scratches, rust, particles?).
•  If necessary, honing was carried out.
• The inner surface is wiped with clean oil + cloth.
• A thin film of oil was left on the inner surface (not left dry).

4. Piston Rod Cleaning

• The piston rod was wiped with solvent and a clean cloth.
• A layer of rust, dirt or grease has been completely removed.
• Scratch or chrome plating damage checked.
• No sanders or wire brushes were used.

5. Sealing Elements

• Old seals and O-rings were dismantled.
• Mattress surfaces have been cleaned.
• The new seals were installed clean and lubricated.
• No contaminants came into contact during assembly.

6. Post-Assembly Controls

•  After the cylinder was collected, some filtered hydraulic oil was added to it.
• The piston rod was moved back and forth by hand and the inner surface was lubricated.
• The grease and dirt remaining on the outer surface has been removed.
• The cylinder was made ready to be mounted on flushed lines.

7. Final Approval

• The cylinder cleaning process is complete.
• All parts were assembled completely.
• The registration form was completed and entered into the maintenance report.

This procedure is a step-by-step guide for maintenance technicians  .