Hydraulic line tubes are an integral part of hydraulic systems, which are used in various applications such as automotive, industrial machinery, construction equipment, and aircraft. Hydraulic Line Tubes (HPL) are seamless cold-drawn precision tubes primarily designed for use as pressure lines in hydraulic or pneumatic equipment. These tubes are versatile and find applications in a wide range of scenarios.

 

 

- Size Range:

  - Outside Diameter: 4mm to 80mm

  - Wall Thickness: 0.75mm to 12.50mm

- Technical Standards:

  - EN 10305-4 (Previously DIN 2391 and DIN 1630)

- Tolerances:

  - According to table HPL Tubes

- Steel Grades:

  - E235 (ST37.4) and E355 (ST52.4)

- Delivery Condition:

  - +N (NBK) Normalised

- Design of Wall Thickness:

  - DIN 2413-1 Load Case I, II, or III

 

The final heat treatment provides HPL tubing with excellent cold workability, allowing for processes such as bending and flaring. It is important to consider the reduction in wall thickness on the outer bend and the out-of-roundness on the inner bend when performing bending operations.

 

These tubes are weldable without the need for preheating and post-weld heat treatment, following standard welding procedures.

 

All hydraulic line tubes come with corrosion protection:

- HPL Tubes Black:

  - Internal and external surfaces lubricated for di < 6mm

  - Internal and external surfaces phosphatized and lubricated or only lubricated for di > 6mm

- HPL Tubes Galvanised - Cr 6 Free - High-Performance Passivation:

  - Externally galvanized tubes with a Zinc coating of 8 to 12 microns

  - Subsequently passivated or chromated

  - Temporary corrosion protection (inhibitor containing mineral) for resistance against white corrosion

 

- In fixed lengths as required

- Ends square cut, un-worked; tubes with OD < 8 mm or ID <= 4 mm also have ends square cut, un-worked, and sealed with plugs or caps

- ID <= 6 mm internal and external surfaces lubricated (only for non-pinched off ends)

- ID >= 6 mm internal and external surfaces phosphatized and lubricated or only lubricated (only for non-pinched off ends)

- Tubes with inside diameter <= 4 mm sealed with plastic caps

- Tubes with inside diameter < 4 mm sealed with plastic plugs

- Eddy current tested according to DIN EN 10246, Part 3, class E3H

- Marking: Continuously marked along a line parallel to the tube axis with manufacturer, steel grade, dimension (OD and wall), and test code

- Mill Test Certificate 3.1. according to DIN EN 10204:2005

- Packed in seaworthy fumigated wooden boxes