ST52.4 DIN 1630 Cold Drawn Seamless Precision Steel Tube for Hydraulic Systems
DIN 1630 St 52.4 Cold-Drawn Seamless Precision Tube for Hydraulic System
Material
DIN 1630 St 52.4 (ST52.4) is a high-performance non-alloy carbon steel used to produce seamless, cold-drawn precision tubes for demanding service such as hydraulic and pneumatic systems, pipework, vessels, and general mechanical engineering.
In many supply chains, St52 / St52.4 is cross-referenced to EN grades such as E355 (1.0580) for hydraulic precision tubes.
Specifications
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Product type: Cold-drawn seamless precision tube (small OD / tight tolerance) for hydraulic lines and components.
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Primary grade: DIN 1630 St 52.4
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Typical alternative spec (hydraulics): EN 10305-4 E355 (+N), seamless cold drawn tubes for hydraulic & pneumatic power systems.
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Delivery condition (EN 10305-4): +N (normalized in controlled atmosphere after final cold drawing).
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Surface roughness (EN 10305-4): Ra ≤ 4 μm (optionally Ra ≤ 2 μm for inner surface when specified).
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Standard lengths (EN 10305-4): 6 m +50/0 mm (standard) or 6 m +10/0 mm (exact), unless otherwise agreed.
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Corrosion protection: Tubes are delivered with temporary corrosion protection; enhanced protections such as phosphating or electro-galvanizing are widely used for hydraulic line durability.
Main Features
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Seamless structure to minimize risk points versus welded tubing in pressure service.
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Cold-drawn precision with defined tolerances and controlled surface quality, supporting leak-free fittings and stable flow.
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Hydraulic-ready quality controls (chemical, tensile, dimensional, and leak-tightness verification; optional NDT for longitudinal imperfections).
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High strength option (St 52.4 / E355) suitable for higher pressure and higher load hydraulic components.
Our Advantages
1) “Can you guarantee tight tolerances and smooth ID/OD for reliable sealing and assembly?”
Yes. For hydraulic projects we can supply to EN 10305-4, which is explicitly characterized by precisely defined tolerances and a specified maximum surface roughness; the standard requires Ra ≤ 4 μm (and allows an inner-surface upgrade to Ra ≤ 2 μm when specified).
2) “How do you control leak risk and defects (especially for high-pressure hydraulics)?”
We follow a “hydraulic-first” inspection plan: chemical analysis, tensile testing, dimensional inspection, and leak-tightness verification on each individual tube are part of EN 10305-4’s inspection framework, with optional NDT for longitudinal imperfections using eddy current / flux leakage / ultrasonic methods and leak-tightness verification per EN ISO 10893-1.
3) “What corrosion protection and surface treatment options are available for storage and harsh service?”
Tubes are delivered with temporary protection against corrosion per EN 10305-4, and we can offer common hydraulic line finishes such as phosphating (improves rust resistance and oil retention) or electro-galvanizing depending on your installation environment and OEM requirements.
Chemical Composition
| Standard | Grade | C (max, %) | Si (max, %) | Mn (%)* | P (max, %) | S (max, %) | Altot (min, %) |
|---|---|---|---|---|---|---|---|
| DIN 1630 | St 37.4 | 0.170 | 0.035 | ≥0.35 | 0.040 | 0.040 | — |
| DIN 1630 | St 44.4 | 0.200 | 0.035 | ≥0.40 | 0.040 | 0.040 | — |
| DIN 1630 | St 52.4 | 0.220 | 0.550 | ≤1.60 | 0.040 | 0.035 | — |
| EN 10305-4:2016 | E235 (1.0308) | 0.17 | 0.35 | 1.20 | 0.025 | 0.015 | 0.015 |
| EN 10305-4:2016 | E355 (1.0580) | 0.22 | 0.55 | 1.60 | 0.025 | 0.015 | 0.020 |
Mechanical Properties
| Standard | Grade | Yield Strength (min, MPa) | Tensile Strength (MPa) | Elongation A (min, %) |
|---|---|---|---|---|
| DIN 1630 | St 37.4 | 235 | 350–480 | 25 |
| DIN 1630 | St 44.4 | 275 | 420–550 | 21 |
| DIN 1630 | St 52.4 | 355 | 500–650 | 21 |
| EN 10305-4:2016 | E235 | 235 | 340–480 | 25 |
| EN 10305-4:2016 | E355 | 355 | 490–630 | 22 |
Execution Standards
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DIN: DIN 1630 (legacy high-performance seamless tubes; still referenced for older specs).
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EN: EN 10305-4 (seamless cold drawn tubes for hydraulic & pneumatic power systems; +N delivery condition).
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ASTM: ASTM A519/A519M (seamless carbon & alloy steel mechanical tubing, hot-finished or cold-finished).
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SAE: SAE J524 (cold drawn and annealed seamless low-carbon steel pressure tubing for hydraulic lines).
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GOST: GOST 9567-75 (precision steel tubes; scope includes high precision production).
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JIS: JIS G 3445 (carbon steel tubes for machine structure and machine parts).
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GB: GB/T 3639-2021 (seamless cold-drawn/cold-rolled precision tubes for mechanical structures, hydraulic equipment, auto parts).
Application Areas
Typical industries: hydraulic & pneumatic systems, mobile equipment, industrial machinery, automotive, general mechanical engineering.
Where it is used (examples):
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Hydraulic power units & pipelines: rigid hydraulic lines, manifolds connections, pressure lines.
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Hydraulic cylinders: cylinder tube lines, control lines, auxiliary piping.
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Automotive & mobility: steering systems, shock absorber-related fluid lines, machine-part tubing where precision OD/ID matters.
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Factory automation: pneumatic/hydraulic actuator lines requiring consistent surface and dimensional quality.
Q: Are you trading company or manufacturer ?
A: manufacturer,also can do trading.
Q: How long is your delivery time?
A: Generally speaking,it is 10-15 days if the goods are in stock,or it is 30-40 days if the goods are not in stock,
it is according to quantity.
Q: Do you provide samples? is it free or extra ?
A: Yes, we could offer the sample for free charge but need pay the cost of freight.
Q: What is your terms of payment ?
A: Payment<=2000USD, 100% in advance. Payment>=2000USD, 30% T/T in advance ,balance before shippment.
If you have another question, pls feel free to contact with me.
Get in Touch
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