In modern industrial fields, particularly in the design and manufacturing of hydraulic and pneumatic systems, demands for component precision and reliability are exceptionally stringent. Among these, piping—the core of fluid transmission—directly determines the efficiency and safety of the entire system. EN 10305-4 precision steel tubes are engineered precisely for such high-demand applications. With their outstanding properties, they have become the preferred choice for engineers and procurement professionals.
EN 10305-4 precision steel tubes are high-precision, seamless, cold-drawn steel tubes produced according to the European standard EN 10305. They are primarily used in hydraulic and pneumatic systems. The standard specifies the dimensional tolerances, surface quality, and performance requirements for precision steel tubes. This makes them the material of choice for engineering applications with stringent requirements for dimensional accuracy and mechanical properties.
Compared to standard steel tubes, EN 10305-4 precision tubes offer superior dimensional accuracy, excellent surface finish, and consistent mechanical properties, ensuring reliable operation of hydraulic and pneumatic components.
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What is the EN 10305-4 standard?
EN 10305-4 is the European standard for cold-drawn seamless precision steel tubes for hydraulic and pneumatic systems.
This European Standard specifies the technical delivery conditions for seamless cold drawn steel tubes of circular cross section used in hydraulic and pneumatic power systems. Tubes according to this document are characterized by having precisely defined tolerances on dimensions and a specified maximum surface roughness.
The allowed pressure rates and upper temperatures are the responsibility of the customer in accordance with the state of the art and in application of the safety coefficients specified in the applicable regulations, codes or standards. Concerning the lower temperature range applicability the impact energy requirement are given at 0℃.
EN 10305-4 Steel Tubes Specification
| Product | Precision seamless steel tubes | for pressure hydraulic and pneumatic lines – HPL |
| Standard | EN |
| Dimensional standard | 10305-4 | Steel tubes for precision applications. Part 4 – Seamless cold drawn tubes for hydraulic and pneumatic power system. |
| Steel grade | E215, E235, E355 |
| Surface coating | Phosphated |
Advantages of EN 10305-4 Precision Steel Tubes
High-precision dimensional tolerances: Precise control of outer diameter, inner diameter, and wall thickness facilitates subsequent processing and assembly.
Excellent surface quality: Smooth inner and outer walls reduce fluid resistance and enhance sealing performance.
Excellent Mechanical Properties: High strength and toughness ensure safe operation under high-pressure conditions.
Suitable for Further Processing: Compatible with various manufacturing processes including galvanizing, cutting, bending, and welding.
Reliable Cleanliness: Widely used in hydraulic and pneumatic systems requiring high cleanliness and low contamination.
Chemical Composition
| Steel grade | % by mass | ||||||
| Steel name | Steel number | C | Si | Mn | P | S a | Al total b min. |
| max. | max. | max. | max. | max. | |||
| E215 | 1.0212 | 0,10 | 0,05 | 0,70 | 0,025 | 0,025 | 0,025 |
| E235 | 1.0308 | 0,17 | 0,35 | 1,20 | 0,025 | 0,025 | 0,015 |
| E355 | 1.058 | 0,22 | 0,55 | 1,60 | 0,025 | 0,025 | 0,020 |
| Elements not quoted in this table (but see footnote b ) shall not be intentionally added to the steel without the agreement of the purchaser, except for elements which may be added for the purposes of deoxidation and/or nitrogen binding. All appropriate measures shall be taken to prevent the addition of undesirable elements from scrap or other materials used in the steel making process. | |||||||
| a This requirement is not applicable provided the steel contains a sufficient amount of other nitrogen binding elements, such as Ti, Nb or V. If added, the content of these elements shall be reported in the inspection document.When using titanium, the manufacturer shall verify that (Al + Ti/2) ≥ 0,020. | |||||||
Permissible Deviations of the Product Analysis
| Element | Specified limit of the cast | Permissible deviation of |
| Analysis , % by mass | the product analysis, % by mass | |
| C | ≤ 0,22 | + 0,02 |
| Si | ≤ 0,55 | + 0,05 |
| Mn | ≤ 1,60 | + 0,10 |
| P | ≤ 0,025 | + 0,005 |
| S | ≤ 0,015 | + 0,003 |
| Al | ≥ 0,015 | – 0,005 |
Mechanical Property
| Steel grade | Yield strength a R eH | Tensile strength | Elongation after Fracture | |
| Steel name | Steel number | min.MPa | R m MPa | A min.% |
| E215 | 1.0212 | 215 | 290 to 430 | 30 |
| E235 | 1.0308 | 235 | 340 to 480 | 25 |
| E355 | 1.058 | 355 | 490 to 630 | 22 |
| The steel grades defined in this document have an intrinsic minimum transverse impact energy of 27 J at 0 °C. | ||||
| a For tubes with outside diameter D ≤ 30 mm and wall thickness T ≤ 3 mm, the R eH minimum values are 10 MPa lower than the values given in this table. | ||||
Manufacturing process
- Steelmaking process
The steel making process is at the discretion of the manufacturer with the exception that the open hearth (Siemens-Martin) process shall not be employed unless in combination with a secondary steelmaking or ladle refining process.
Steels shall be fully killed.
NOTE – This excludes the use of rimming, balanced or semi-killed steel.
2. Tube manufacture and delivery conditions
The tubes shall be manufactured from hot finished seamless hollows by cold drawing.
The tubes shall be delivered in the delivery condition +N which means that after the final cold drawing operation the tubes are normalized in a controlled atmosphere.
All non-destructive testing (NDT) activities shall be carried out by qualified and competent level 1, 2 and/or 3 personnel authorized to operate by the employer.
The qualification shall be in accordance with ISO 11484:2009 or, at least, an equivalent to it.
It is recommended that the level 3 personnel be certified in accordance with EN ISO 9712 or, at least, an equivalent to it.
The operating authorization issued by the employer shall be in accordance with a written procedure. NDT operations shall be authorized by a level 3 NDT individual approved by the employer.
Dimensions and Tolerances
| Specified outside diameter | Specified inside diameter d | Specified wall thickness T with tolerance a | |||
| D with tolerance a | with tolerance a | ||||
| 4 | ±0,08 | 3 | ±0,15 | 0,5 | ±0,10 |
| 2 | 1 | ±0,10 | |||
| 5 | ±0,08 | 3,5 | ±0,15 | 0,75 | ±0,10 |
| 3 | 1 | ±0,10 | |||
| 6 | ±0,08 | 4 | ±0,12 | 1 | ±0,10 |
| 3 | ±0,15 | 1,5 | ±0,15 | ||
| 2 | 2 | ±0,20 | |||
| 8 | ±0,08 | 6 | ±0,10 | 1 | ±0,10 |
| 5 | 1,5 | ±0,15 | |||
| 4 | ±0,15 | 2 | ±0,20 | ||
| 3 | 2,5 | ±0,25 | |||
| 10 | ±0,08 | 8 | ±0,08 | 1 | ±0,10 |
| 7 | ±0,12 | 1,5 | ±0,15 | ||
| 6 | ±0,15 | 2 | ±0,20 | ||
| 5 | 2,5 | ±0,25 | |||
| 12 | ±0,08 | 10 | ±0,08 | 1 | ±0,10 |
| 9 | ±0,10 | 1,5 | ±0,15 | ||
| 8 | ±0,12 | 2 | ±0,20 | ||
| 7 | ±0,15 | 2,5 | ±0,25 | ||
| 6 | 3 | ±0,30 | |||
| 14 | ±0,08 | 12 | ±0,08 | 1 | ±0,10 |
| 11 | 1,5 | ±0,15 | |||
| 10 | ±0,10 | 2 | ±0,20 | ||
| 9 | ±0,12 | 2,5 | ±0,25 | ||
| 8 | ±0,15 | 3 | ±0,30 | ||
| 15 | ±0,08 | 13 | ±0,08 | 1 | ±0,10 |
| 12 | 1,5 | ±0,15 | |||
| 11 | ±0,10 | 2 | ±0,20 | ||
| 10 | ±0,12 | 2,5 | ±0,25 | ||
| 9 | ±0,15 | 3 | ±0,30 | ||
| 16 | ±0,08 | 14 | ±0,08 | 1 | ±0,10 |
| 13 | 1,5 | ±0,15 | |||
| 12 | ±0,10 | 2 | ±0,20 | ||
| 11 | ±0,12 | 2,5 | ±0,25 | ||
| 10 | ±0,15 | 3 | ±0,30 | ||
| 18 | ±0,08 | 16 | ±0,08 | 1 | ±0,10 |
| 15 | 1,5 | ±0,15 | |||
| 14 | 2 | ±0,20 | |||
| 13 | ±0,15 | 2,5 | ±0,25 | ||
| 12 | 3 | ±0,30 | |||
| 20 | ±0,08 | 17 | ±0,08 | 1,5 | ±0,15 |
| 16 | 2 | ±0,20 | |||
| 15 | ±0,15 | 2,5 | ±0,25 | ||
| 14 | 3 | ±0,30 | |||
| 13 | 3,5 | ±0,35 | |||
| 12 | 4 | ±0,40 | |||
| 22 | ±0,08 | 20 | ±0,08 | 1 | ±0,10 |
| 19 | 1,5 | ±0,15 | |||
| 18 | 2 | ±0,20 | |||
| 17 | 2,5 | ±0,25 | |||
| 16 | ±0,15 | 3 | ±0,30 | ||
| 15 | 3.5 | ±0,35 | |||
| 14 | 4 | ±0,40 | |||
| 25 | ±0,08 | 22 | ±0,08 | 1,5 | ±0,15 |
| 21 | 2 | ±0,20 | |||
| 20 | 2,5 | ±0,25 | |||
| 19 | ±0,15 | 3 | ±0,30 | ||
| 17 | 4 | ±0,40 | |||
| 16 | 4.5 | ±0,45 | |||
| 15 | 5 | ±0,50 | |||
| 28 | ±0,08 | 25 | ±0,08 | 1,5 | ±0,15 |
| 24 | 2 | ±0,20 | |||
| 23 | 2,5 | ±0,25 | |||
| 22 | ±0,15 | 3 | ±0,30 | ||
| 20 | 4 | ±0,40 | |||
| 18 | 5 | ±0,50 | |||
| 30 | ±0,08 | 26 | ±0,08 | 2 | ±0,20 |
| 25 | 2,5 | ±0,25 | |||
| 24 | ±0,15 | 3 | ±0,30 | ||
| 22 | 4 | ±0,40 | |||
| 20 | 5 | ±0,50 | |||
| 18 | 6 | ±0,60 | |||
| 35 | ±0,15 | 31 | ±0,15 | 2 | ±0,20 |
| 30 | 2,5 | ±0,25 | |||
| 29 | 3 | ±0,30 | |||
| 27 | 4 | ±0,40 | |||
| 25 | 5 | ±0,50 | |||
| 23 | 6 | ±0,60 | |||
| 38 | ±0,15 | 34 | ±0,15 | 2 | ±0,20 |
| 33 | 2,5 | ±0,25 | |||
| 32 | 3 | ±0,30 | |||
| 30 | 4 | ±0,40 | |||
| 28 | 5 | ±0,50 | |||
| 26 | 6 | ±0,60 | |||
| 24 | 7 | ±0,70 | |||
| 22 | 8 | ±0,80 | |||
| 42 | ±0,20 | 38 | ±0,20 | 2 | ±0,20 |
| 36 | 3 | ±0,30 | |||
| 34 | 4 | ±0,40 | |||
| 32 | 5 | ±0,50 | |||
| 30 | 6 | ±0,60 | |||
| 26 | 8 | ±0,80 | |||
| 50 | ±0,20 | 42 | ±0,20 | 4 | ±0,40 |
| 40 | 5 | ±0,50 | |||
| 38 | 6 | ±0,60 | |||
| 34 | 8 | ±0,80 | |||
| 32 | 9 | ±0,90 | |||
| 30 | 10 | ±1,00 | |||
| 55 | ±0,25 | 47 | ±0,25 | 4 | ±0,40 |
| 43 | 6 | ±0,60 | |||
| 39 | 8 | ±0,80 | |||
| 35 | 10 | ±1,00 | |||
| 60 | ±0,25 | 50 | ±0,25 | 5 | ±0,50 |
| 44 | 8 | ±0,80 | |||
| 40 | 10 | ±1,00 | |||
| 35 | 12.5 | ±1,25 | |||
| 70 | ±0,30 | 60 | ±0,30 | 5 | ±0,50 |
| 54 | 8 | ±0,80 | |||
| 50 | 10 | ±1,00 | |||
| 45 | 12.5 | ±1,25 | |||
| 80 | ±0,35 | 68 | ±0,35 | 6 | ±0,60 |
| 64 | 8 | ±0,80 | |||
| 60 | 10 | ±1,00 | |||
| 55 | 12.5 | ±1,25 | |||
| a Dimensions and tolerances only apply for the ordered pair of dimensions | |||||
Applications of Precision Steel Tubes
Hydraulic Systems: Hydraulic cylinders, hydraulic piping
Pneumatic Systems: Pneumatic equipment, pneumatic control devices
Automotive Industry: Brake lines, power steering systems
Construction Machinery: Hydraulic piping for excavators, loaders
Industrial Equipment: Machine tools, production lines, automation equipment
Energy and Power: Power generation equipment, control piping for wind power systems
You can get an offer for products in below material forms:
-Pipe and Tube (EN 10216-5, ASTM A213, ASTM A249, A312, A790,)
-Forged Fitting and Flange (ASTM A182 , ASTM A105,ASTM B564 )
-Butt Weld Fittings (ASTM A234, ASTM A403,ASTM A815)
-Round bar , Billet (ASTM A276, ASTM A479)
– Plate, Sheet, Strip(ASTM A240, EN 10028-7, A480)
-Bolting, Nuts（ASTM A193, A194, A320）