INSIDE SKIVED&ROLLER BURNISHED COLD FINISHED TUBES
- EN 10305-1
- EN 10305-4
- EN ISO 286-2
|Used for||- Hydraulic cylinders|
TMK HYDRA ART identification
TMK Hydra ArtH xxx OD x ID / TMK Hydra ArtH xxx OD x ID –IFR
TMK Hydra is the TMK-Artrom classification of Cold drawn inside skived and roller burnished (SRB) tubes.
Art H xxx is the grade identification, xxx being the minimum granted yield point in Mpa.
OD, ID are outside and inside diameters nominal values.IFR - Improved Fatigue Resistance – is an optional finishing which increase the Fatigue resistance on cycling stress specific for hydraulic cylinders use.
Size program according Table 1 (Intermediate sizes can be produced subject of agreement before ordering).
- Outside Diameter (OD) in accordance with EN 10305-1
- Inside Diameter (ID) in accordance with ISO H8 – EN ISO 286-2, Ra – 0.3 µm or better (please see Table 1).
Note: On request, OD can be supplied only on agreed positive tolerances suitable for future machining (for example for telescopic cylinders). For such purpose the tubes can be pre-machined using a center-less grinding process, the final OD value and OD variation being necessary to be agreed.
- Max 0.5 mm/1000 mm
- Total deviation for tubes with length 6 m: max. 3.5 mm/length.
- Total deviation for tubes with length > 6 m: for each meter over 6 m the tolerance must be increased by 0.5 mm.
|Roundness and eccentricity||
- OD and ID roundness deviation shall be within the limits of the OD and ID tolerances.
- Eccentricity shall be maximum 5%.
- Eccentricity calculated by formula:
Where Wt max, Wt min are maximum and minimum measured wall thickness in same cross-section.
|Chemical composition (%)|
|Tube ends preparation||
- Square cut to the longitudinal axis of the tubes with a slight bevel on outside surface.
- Protected with plastic caps.
- Minimum and maximum manufacturing lengths according to Table 1. Usually, the tubes shall be supplied in random lengths within 2 m variation.
- As an option fix lengths or multiple of fix length are available with cutting tolerance of -0/100 mm as well as cut to length pieces in range 0.4 - 4 m, cutting tolerance of -0/+3 mm.
|Surface protection||Inside and outside surface oiled by immersion in corrosion preventive oil in order to ensure temporary protection against corrosion during about 6 months storage in covered area, out of excessive humidity and/or direct water contact.|
|Marking||Continuous marking along the length of the tube with following information: manufacturer’s logo, dimension (OD x ID), steel grade, heat number and the number of standard or other data as per the customers’ request.|
|Packaging|| Packed in bundles with circular or hexagonal cross-section, bundle weight of maximum 2000 kilograms.
The bundles are tied with protected metallic straps to provide protection against mechanical damage and corrosion during storage and in transit.
|Mill test report||Mill test reports are issued to customer requirements. Usually it comply with EN 10204 – 3.1|