Industrial machinery hydraulic repair service

Workshop repair service for leaking hydraulic cylinders and oil leakage

VietSonic provides inspection, measurement, repair, and restoration services for hydraulic cylinders with oil leakage, seal failure, scratched piston rods, worn guide bushings, or pressure loss during operation.

On-machine inspection
Actual dimensional measurement
Seal replacement and piston rod restoration
Installation, alignment, and test run

Technician measuring a hydraulic cylinder before repair

A leaking hydraulic cylinder should not be fixed by simply replacing the seals

A hydraulic cylinder is a key actuator in many types of industrial machinery. When a cylinder leaks oil, loses pressure, or has external oil leakage, the machine may become weak, lose pressing force, move unstably, contaminate the work area, and directly affect production efficiency.

From actual on-site inspection images, the technician can be seen measuring the piston rod diameter, installation height, mounting distance, and recording the condition of hydraulic oil leaking onto the machine floor. This is an important step to identify the correct cause before repair.

For hydraulic cylinders that have been in operation for a long time, simply replacing the seals without inspecting the piston rod, guide bushings, cylinder barrel, and mounting alignment can cause the oil leakage problem to return after a short period of use.

Technician measuring the hydraulic cylinder piston rod diameter with a caliper
The technician measures the piston rod size to determine the proper repair method, seal replacement, or machining restoration solution.

Signs that a hydraulic cylinder needs inspection

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Common visible signs

Hydraulic oil leaking onto the machine floor
The cylinder body or rod end is wet with oil
The cylinder operates weakly and lacks force
The cylinder rod moves slowly, jerks, or moves unevenly
The machine loses pressure and cannot hold position
The piston rod is scratched, pitted, bent, or contaminated
Oil leakage appears around the sealing area
Abnormal noise occurs during machine operation

Why should it be handled early?

If the machine continues operating while oil is leaking, the system may suffer pressure loss, excessive hydraulic oil consumption, contamination in the production area, and increased risk of damage spreading to other components.

In particular, oil leaking onto the floor not only affects cleanliness but can also create a slipping hazard for operators, while making machine maintenance harder to control.

Hydraulic oil leaking onto the machine floor due to a leaking hydraulic cylinder
Oil appearing under the machine is a typical sign of a hydraulic cylinder with oil leakage or external leakage.

Common causes of hydraulic cylinder oil leakage

Worn or hardened seals

After long-term operation, seals are exposed to pressure, friction, and high temperature, which can cause aging, cracking, wear, or loss of sealing performance.

Scratched or pitted cylinder rod surface

When the rod surface is scratched, the seal can be damaged quickly, causing oil to leak during cylinder operation.

Worn guide bushings

Worn guide bushings can cause rod misalignment, uneven friction, faster seal damage, and repeated oil leakage problems.

Misaligned installation or incorrect mounting position

If the cylinder is installed off-center, the applied force will not follow the correct axis, causing the rod, bushings, and seals to wear out quickly. Therefore, measuring the mounting assembly is an essential step.

Measuring the installation height of a hydraulic cylinder
Measuring the hydraulic cylinder mounting distance on the machine
Mounting assembly and hydraulic cylinder installation position that require inspection

Why is measurement required before repairing a hydraulic cylinder?

Not every case can be solved by replacing the seals only. For cylinders that have operated for many years, the actual dimensions and condition must be carefully checked before deciding on the repair method.

The parameters commonly inspected include piston rod diameter, cylinder body outer diameter, overall length, stroke length, mounting hole center distance, mounting lug size, mounting pins, bushings, and the cylinder installation position on the machine.

Measurement helps determine whether the cylinder requires seal replacement, piston rod restoration, guide bushing machining, cylinder head repair, or remanufacturing of mounting components.

Parameters that should be recorded

  • Cylinder piston rod diameter.
  • Outer diameter/cylinder body diameter.
  • Overall length and working stroke.
  • Mounting hole center distance, mounting lugs, and mounting pins.
  • Cylinder installation position on the machine.
  • Oil leakage condition, contamination level, and leakage points.

Technician measuring the hydraulic cylinder installation position directly on the machine with a measuring tape
Direct measurement on the machine helps determine the correct restoration dimensions and reduces errors during reinstallation.

Service items performed by VietSonic

Oil leakage inspection

Identify the leakage point: rod end, end cap, cylinder body, fittings, oil hoses, or sealing area.

Hydraulic cylinder disassembly and inspection

Evaluate the condition of seals, guide bushings, piston rod, cylinder barrel, threads, connectors, and related components.

Hydraulic cylinder seal replacement

Replace the seal set according to the cylinder size, working pressure, and operating conditions.

Hydraulic piston rod restoration

Handle scratched, pitted, worn, or slightly bent rods depending on the actual condition of the equipment.

Machining of bushings, pins, and mounting lugs

When the mounting assembly is worn, misaligned, or no spare parts are available, it can be measured, drawn, and machined according to the existing condition.

Installation, alignment, and test run

After repair, the cylinder must be installed in the correct position and checked for sealing performance, stability, and pressure-holding capability during operation.

Hydraulic cylinder repair process

Information intake

Collect images, videos, and descriptions of oil leakage, external leakage, or weak machine force.

On-machine inspection

Check the leakage position, measure the cylinder dimensions, and inspect the related mounting assembly.

Repair method proposal

Determine whether the cylinder requires seal replacement, rod restoration, bushing machining, or mounting assembly repair.

Machining and repair

Restore or replace components according to the actual measured dimensions.

Installation and test run

Check sealing performance, operating stability, pressure-holding capability, and hand over the equipment.

Benefits of proper technical repair

Fix oil leakage and external leakage.
Reduce hydraulic oil loss.
Restore the cylinder’s pushing/pulling force.
Help the machine operate more stably.
Limit repeated failures after repair.
Reduce the risk of unexpected machine downtime.
Save costs compared with replacing the entire cylinder.
Enable proactive repair for old cylinders or cylinders with hard-to-find spare parts.

Inspecting the hydraulic cylinder assembly after measuring the current condition
The measurement, restoration, and machining approach based on the actual condition helps effectively repair hydraulic cylinders that have been operating for many years.

VietSonic provides hydraulic cylinder repair for industrial machinery

If your equipment shows signs of oil leaking onto the floor, weak cylinder operation, oil leakage at the rod end, or pressure loss during operation, contact VietSonic for advice on a suitable inspection and repair solution.

Hydraulic cylinder repair
Cylinder seal replacement
Piston rod restoration
Oil leakage repair

Contact information

Vietnam Ultrasonic Equipment Co., Ltd.

Phone: 0938 49 33 66 – Mr. Hải

Email: info.vietsonic@gmail.com

Website: https://vietsonic.vn