Seamless Steel Pipe
Hydraulic Cylinder Seamless Steel Tube
Precision cold drawn seamless steel tubes for hydraulic cylinder barrels - inner diameter tolerance within ±0.02 mm and bore finish Ra within 0.2 um, sizes 50x32 to 100x80 mm in SAE 1020, C45, 28Mn6, 34CrMo4 / 42CrMo4 and S355JR / A572 Gr50.
Specifications
- Application
- Hydraulic cylinder barrels for construction, mining, metallurgy and industrial machinery
- Size Range (OD x ID)
- 50x32, 60x40, 70x50, 83x63, 90x70, 100x80 mm
- Grades
- SAE 1020 / C45; 28Mn6 (EN) / 27SiMn; 34CrMo4 / 42CrMo4 (EN); S355JR / A572 Gr50
- Bore Tolerance
- Inner diameter tolerance within ±0.02 mm
- Bore Finish
- Surface roughness Ra within 0.2 um
- Cleanliness
- NAS 7-8 - protects sensitive servo valves
- Process
- Cold drawn, high-tensile seamless
- Standards
- ASTM and EN international standards (ASTM A519 / EN grade system).
Product Overview
Precision cold drawn seamless steel tubes for hydraulic cylinder barrels, matched grade by grade to the working pressure of the cylinder. SAE 1020 and C45 give cost-effective machinability for low-pressure light-duty general machinery; 28Mn6 (EN) and 27SiMn balance strength, toughness and weldability for forklift, crane and medium-pressure injection-moulding cylinders; 34CrMo4 and 42CrMo4 offer hardenability and fatigue resistance for mining, metallurgy and ultra-high-pressure duty; S355JR and A572 Gr50 HSLA cover general heavy-load cylinders in construction and agricultural machinery.
Specifications and Standards
Sizes run from 50x32 mm to 100x80 mm (OD x ID). Inner diameter tolerance is held within ±0.02 mm and bore roughness within Ra within 0.2 um, with NAS 7-8 cleanliness so servo valves are not contaminated in service. Tubes are cold drawn and supplied high-tensile seamless, compliant with ASTM and EN standards.
Applications
Excavators and heavy cranes operating at pressures up to 42 MPa, where high-precision tubes keep the cylinder leak-free under extreme shock loads - in a leading construction-machinery OEM programme the leakage rate fell by 67 percent and MTBF rose from 1,200 to 2,100 hours. In injection moulding and hydraulic presses the same uniformity supports micron-level position control, with ultra-high cleanliness protecting sensitive servo valves.
Ordering Information
Send OD x ID, grade, quantity and bore tolerance requirement to melinda@spai-steel.com - we confirm supply and lead time. Tighter tolerances and non-standard sizes: see our Customized Fittings Experts page.