ST52 Honed Cylinder Tube & ST52 Seamless Pipe
1. Overview & Material Properties
As a premier seamless honed tube manufacturer, we engineer precision steel tubes specifically designed for hydraulic cylinder barrels. The ST52 tube (DIN 2391 / DIN 1629 standard, equivalent to E355) is the gold standard in the fluid power industry. Thanks to its low-carbon, high-manganese chemical composition, an ST52 seamless pipe offers outstanding weldability, superior tensile strength (≥ 580 MPa), and excellent machinability.
Whether you need a reliable ST52 honed cylinder tube or custom-machined hydraulic parts, our one-stop manufacturing solutions ensure structural integrity under extreme fluid pressures.
Material: ST52.3 / ST52.4 seamless steel
Finishing: Honing or Skiving & Roller Burnishing (SRB) for optimal bore quality and H8 tolerance.
Additional Services: CNC machining for customized cylinder parts based on client drawings.
2. Commodity Name
ST52.3 / ST52.4 Honed Seamless Tube for Hydraulic Cylinders
3. Size Range
| Dimension Parameter | Measurement Range |
|---|
| Inner Diameter (ID) | 30mm – 500mm |
| Outer Diameter (OD) | 40mm – 580mm |
| Length | Up to 12 meters or customized |
4. Available Steel Grades & Equivalents
DIN: ST52, ST52.3, ST52.4 (Core Material)
SAE / AISI: 1020, 1026, 1045, 4130, 4140
EN: E355, C45E, 25CrMo4, 42CrMo4, CK45, S45C, E410, E470
GB: 20#, 45#, 16Mn, Q345B–E, 25Mn, 27SiMn
JIS: STKM 13A, STKM 13C
5. Manufacturing Methods
6. Delivery Conditions
| Code (DIN) | Code (EN) | Condition Description |
|---|
| BK | +C | Cold drawn (hard) |
| BKW | +LC | Cold drawn (soft) |
| BKS | +SR | Stress relieved |
| GBK | +A | Annealed |
| NBK | +N | Normalized |
| Q+T | Q+T | Quenched + Tempered |
7. Bore Treatment & End Finish
Honing: Ra ≤ 0.25 μm (ultra-smooth surface). Ends are plain, square-cut, and burr-free.
Skiving & Roller Burnishing (SRB): Ra ≤ 0.35 μm (high efficiency). Slightly beveled ends.
Both methods strictly meet the H8 tolerance requirements for hydraulic cylinder barrels. Custom ends are available upon request.
8. H8 Tolerance for ST52 Honed Cylinder Tubes
| ID Range (d in mm) | Tolerance (mm) | ID Range (d in mm) | Tolerance (mm) |
|---|
| 18 < d ≤ 30 | +0 / +0.033 | 180 < d ≤ 250 | +0 / +0.072 |
| 30 < d ≤ 50 | +0 / +0.039 | 250 < d ≤ 300 | +0 / +0.081 |
| 50 < d ≤ 80 | +0 / +0.046 | 300 < d ≤ 315 | +0 / +0.081 |
| 80 < d ≤ 120 | +0 / +0.054 | 315 < d ≤ 400 | +0 / +0.089 |
| 120 < d ≤ 180 | +0 / +0.063 | 400 < d ≤ 500 | +0 / +0.097 |
9. Packing & Applications
Our ST52 seamless pipes are securely bundled with steel strips, fitted with plastic end caps, coated with anti-rust oil (internally and externally), and wrapped in PVC or knitted bags. Custom labels are available.
Ideal Applications Include:
Hydraulic cylinder barrels (OEM & aftermarket repair)
Custom ST52 hydraulic cylinder components
High-pressure pneumatic actuators & lifting systems
Seamless tube delivery cylinders for concrete pumps
Frequently Asked Questions
Q1: As a seamless honed tube manufacturer, what is your minimum order quantity (MOQ)?
A: Our MOQ is 2–3 tons/size for OD ≤ 250mm, and 10 tons/size for OD > 250mm. For special alloy grades (E410, E470), the MOQ is 10 tons.
Q2: What is the typical delivery time for an ST52 honed cylinder tube?
A: Typical lead time is 40–60 days depending on the size and quantity. Small bore tubes with high precision may take up to 30 days for the honing process alone.
Q3: Do you offer custom cylinder parts from ST52 seamless pipes?
A: Yes, our factory provides complete CNC machining services including turning, boring, and grooving directly from our ST52 tube stock.
Q4: How do you ensure the quality of your ST52 tubes?
A: 90% of our raw materials are sourced from certified major mills. We implement a full-stage inspection protocol encompassing dimensional, surface roughness, and mechanical properties testing.
Company Profile
Founded in 2002, Chengxin is a globally recognized seamless honed tube manufacturer. We operate a 32,000㎡ factory equipped with 12 specialized workshops. Our facility houses advanced hydraulic cold drawing benches, dedicated honing & SRB production lines, and in-house die-making capabilities. We proudly serve hydraulic cylinder OEMs and machinery manufacturers worldwide with premium ST52 seamless pipes and fully customized cylinder parts.
