How to Prevent Cylinder Scoring? Damages of Dirty Oil
26 November 2025
The cylinder is the pressure chamber of the breaker. The piston moves back and forth inside this part hundreds of times per second. In high-speed breakers like Daemo or MSB, the smoothness of the cylinder surface is vital.
If your hydraulic oil gets dirty or the piston breaks, the inner surface of your cylinder gets scratched (scoring). This is the most expensive failure a breaker can face.
1. How to Prevent Cylinder Scoring?
Tolerances on the inner surface of the cylinder are hair-thin.
- Clean Oil: Metal shavings in hydraulic oil scratch the cylinder like sandpaper. Do not neglect your filters.
- Overheating: If oil exceeds 80°C, the oil film breaks, the piston rubs against the cylinder and seizes.
- Bolt Torque: In Krupp or DNB models, loose tie rods shift the cylinder alignment, causing the piston to rub against the wall.
2. Repair or Replace?
Can a scratched cylinder be saved?
| Damage Status | Process | Notes |
| Hairline Scratches | Honing (Polishing) | Can be saved if within tolerance limits. |
| Deep Gouges | Rectify + Oversize Piston | Cylinder is enlarged, custom piston is made. |
| Crack / Fracture | Must Replace | Cannot be welded, will not hold pressure. |
3. Compatible Brands
At HKM, we manufacture cylinders to original material standards (DIN/ISO). Compatible major brands include:
- Furukawa (FRD): All F and FX series cylinders.
- Soosan & Daemo: SB series, DMB series.
- Rammer & Atlas Copco (Epiroc): S series, E series, SB/MB/HB series.
- Others: MSB, D&A, Okada, Krupp, Indeco, DNB, MTB.