Consequences of Insufficient Machining Accuracy on Cylinder Performance

Cylinder barrel bore requires high machining precision. Surface roughness depends on piston seal type:

• O-ring seals: Grade 3 accuracy, Ra ≤ 0.4 μm
• Y-ring seals: Grade 4–5 accuracy, Ra ≤ 0.4 μm
Cylindricity and roundness errors must not exceed half the dimensional tolerance. Perpendicularity between end face and bore must be within 2/3 of tolerance.

If barrel surface finish is inadequate, friction between seal and bore increases, causing:
• Elevated starting pressure
• Crawling (jerky motion)
• Accelerated seal wear → internal leakage → failure to meet performance specs.

Prevention: Improve machining accuracy of barrel and rod surfaces.