Precision seamless tubes for hydraulic and pneumatic pressure circuits (HPL type)

HPL (High Pressure Line) steel pipes are precision seamless pipes made of high-grade steel, designed and manufactured to transmit liquids and gases in pressure hydraulic and pneumatic circuits with high technical parameters and reliability. These pipes are characterized by excellent mechanical strength, corrosion resistance and high dimensional accuracy, which allows them to be used in demanding industrial applications, such as chemical, petrochemical, automotive, defense, aerospace, automotive, etc.

Features of HPL pipes:

  • high tensile and bending strength – they must withstand high pressure and mechanical loads;
  • exact dimensional tolerances – dimensional precision is crucial for the proper operation of hydraulic and pneumatic systems; HPL pipes must have very precise dimensional tolerances to ensure accurate connections with other system components;
  • smooth inner surface – to prevent dirt from settling and reducing fluid flow;
  • high resistance to corrosion – HPL pipes are exposed to contact with aggressive substances, such as oils, hydraulic fluids, sea water, etc.;
  • resistance to high and low temperatures – HPL pipes must operate in various temperature conditions, therefore they must be made of materials that retain their mechanical and chemical properties over a wide temperature range;
  • shock and vibration resistance – HPL pipes must be shock and vibration resistant to prevent damage and leakage in the hydraulic or pneumatic system;
  • durability and wear resistance – to ensure a long service life and minimal cost of ownership.
Calculate the weight of pipes

Calculate the weight of pipes

Use our calculator to determine the exact weight of pipes you are interested in.


  • EN 10305-4 Steel tubes for precision applications. Part 4: Seamless cold drawn tubes for hydraulic and pneumatic power systems.
  • DIN 2391-1 Seamless precision steel tubes. Part 1: Dimensions.

Steel grades

according to EN: E215 (1.0212), E235 (1.0308), E355 (1.0580)
according to DIN: St 44.4, St 37.4, St 52.4

Mechanical properties in room temperature

Note. For tubes with outside diameter ≤ 30 mm and wall thickness ≤ 3 mm, minimum values of ReH are 10 MPa lower than given above.
Steel grade Yield limit ReH min. MPaTensile strenght Rm min. MPaElongation A min. %
E215 215290 to 430 30
E235235235 to 480 25
E355355490 to 630 22

Delivery condition

+N (EN); NBK (DIN) Normalized (after the last cold drawing process the tubes are normalized in a controlled atmosphere)

Coarseness of the outer and inner surface (starting with ID 15 mm) Ra ≤ 4 μm


  • the length of the maufactured precision tubes is 6 000 mm (tolerances at the standard length is 0+50 mm and at the exact length is 0+10 mm)
  •  exact length can be from the range of 3 000 mm – 9 000 mm


Total deviation: max 0,0015 L
Local deviation: max 3 mm / 1 m

Ends of the tubes

The ends of the tubes are smooth and enclosed with plastic caps.


The electromagnetic nondestructive testing of leak tightness is always performed according to EN 10246-1 or other corresponding standards. Selection of the tests is defined in EN 10305-1. The NDT test and the flattening or drift expanding test is possible.


Each tube is marked by the InkJet system along the whole length according to standards or according to customer requirements. Tube bundles are marked by tags.

Surface protection

– oiled
– phosphated and oiled
– electrolytically galvanized and chrome-coated


The HPL tubes are delivered in bundles with either circular or hexagonal cross-section weighting maximum 2000 kilograms. The tubes are tied with a steel band. Upon agreement it is possible to protect the surface with paper lining or protect the ends of the bundle with PCV foil.

Certificates for HPL tubes