Precision tubes for hydraulic and pneumatic lines – HPL type
Standards and steel grades,
Tube sizes acc. to EN standard,
Tube sizes acc. to ASTM standard,
Tube sizes acc. to JIS standard.
Precision tubes are made using the cold drawing process. The rolled seamless tubes are used as the semi-finished product. Precision tubes HPL types are made from carbon and alloyed steel. Tubes are destined for hydraulic and pneumatic distribution systems and circles. Overview of dimensional standards and technical-delivery conditions of the tubes for hydraulic and pneumatic circles are presented in a separate overview .
separate overview. Steels are produced in an electric arc furnace and they are fully killed. Upon agreement it is possible to deliver other types of steel.
MicropurityAccording to NFA 04 - 106 or ASTM E45 (JK ranking) max. A4-B2-C2-D2. Upon agreement it is also possible to assign according to EN 10247 or ISO 4967 (a – sulphides, B – Alumina, C – silicates, D – Oxides). Grain size meets the EN ISO 643 – 5 and finer.
Allowable pressure for hydraulic and pneumatic linesThe highest allowable pressure for hydraulic and pneumatic lines in relationship to steel and tube testing is presented in tables. Calculation was done according to DIN 2413.
Delivery condition and thermal treatment of the tubes for hydraulic and pneumatic linesTubes are delivered as cold drawn and normalized NBK according to DIN, +SR according to EN, .1 according to STN and N according to ASTM. Overview of other conditions can be found here. Coarseness of the outer and inner surface (starting with 15 mm of the inside diameter) is Ra <= 4 micrometers (0.004mm).
Length of the tubes for hydraulic and pneumatic lines- manufactured length of the precision tubes is 6 meters (tolerances at the standard length is 0 + 50 mm and at the exact length is 0 + 10 mm)
- exact length is in the range of 3 000 - 9 000 mm.
Tolerances of the tubes for hydraulic and pneumatic linesTolerances of the precision tubes meet the appropriate dimensional table standards. Zeleziarne Podbrezova a.s. offers precision tubes with tighter tolerances, i.e. tolerances that are tighter compared with the standard values. Tighter tolerances are presented in a separate table.
Straightness of the tubes for hydraulic and pneumatic lines3 mm / m (1 : 1 000), overall straightness is 0,0015 % maximum of the total length of a tube.
Ends of the HPL tubesThe ends of the tubes are smooth and enclosed with a plastic plugs.
Marking of the HPL tubesEach tube is marked by the InkJet system along the whole length according to standards or according to customer requirements. Tube bundles for hydraulic and pneumatic lines are marked by tags.
Surface protection of the tubes for hydraulic and pneumatic linesThe HPL tubes are delivered as oiled, phosphated or electrolytically galvanized and chrome-coated.
Testing of the HPL tubesThe 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. On the top of it the NDT test and the flattening or drift expanding test is possible.
Certificates for HPL tubesAccording to the following standards: EN 10 204 or DIN 50049
- nonspecified testing - 2.2
- specified testing 3.1.B or 3.1
- upon agreement - 3.1.C or 3.2