Welded aluminium tubes

ALLOYS

Here at Tubes International we sell and process high-frequency welded aluminium alloys: On the tube welding machines of our well-selected suppliers the aluminium tubes are made out of a milled aluminium slug, using the continuous high frequency inductive process, following the principle of resistance pressure welding. Without additional materials many aluminium alloys can be processed, self-hardening and precipitation hardening alloys are up for choice. These thin walled tubes with high thickness accuracy without eccentric deviation are ideal for further processing.

Our delivery possibilities of the welded Al-tubes include round tubes with diameters from 8mm up to over 60mm with wall thicknesses from 0,7mm to 3mm. We also offer welded aluminium profiles such as square tubes, rectangular tubes, oval and flat oval tubes. Special profiles are available on request, our suppliers have their own tooling and can offer correspondingly cheap and well. Since the shaping takes place via roller sets, only small adaptions of some roller stations are often necessary in order to obtain the desired aluminium profile.

The aluminium tubes can be deburred internally during the continuous welding process, i.e. the inner weld seam is planed and the tubes are suitable for telescoping or for mounting of slide-in parts. An internal deburring is also recommended for water-bearing aluminium tubes. The outer weld seam is always removed during the welding process.

A wide range of alloys are available, welded profiles are offered from the more soft alloys of the 3000 series, the main part being the harder alloys of the 5000 series such as 5049 and 5086, and to a lesser extent our customers choose tubes made of aluminium 7075, which have the highest strengths.

Don’t hesitate to contact us for alloy questions or samples.

Aluminiumprofile21
Deliverable realisations::
  • anodized
  • band anodized
  • powder coated
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TOLERANCES

Tolerances according to Euronorm EN 1592 (extract)

External diameter

The outside diameter measured at any point (except the first 100mm from each end) must be within the Tolerances in Table 1.

Table 1: Tolerances for the outer diameter (out-of-roundness included)

Dimensions in millimetres

Nominal outer diameter D Tolerances

8 ≤ D ≤ 15 ± 0.10

15 ˂ D ≤ 40 ± 0.12

40 ˂ D ≤ 60 ± 0.15

60 ˂ D ≤ 80 ± 0.20

Other Tolerances are available by agreement.

For D ≤ 40 mm the measurement should be carried out with a micrometre screw with a graduation of 1/100 millimetres.

At D ˂ 40 mm, the measurements shall be carried out with a measuring slide, which has a measuring accuracy of 1/50 millimetre.

All measurements must be carried out at a distance of at least 100 mm from the end of the tube.

Thickness

The limiting dimensions for the wall thicknesses are given in Table 2.

Table 2: Thickness limit dimensions

Dimensions in millimetres

Nominal thickness t limiting dimensions

0.6 ≤ t ≤ 1.0 ± 0.05

1.0 ˂ t ≤ 2.5 ± 0.08

These limits do not apply to the weld area. Other thicknesses and dimensions can be agreed between producers and purchasers in writing.

Lengths

The tubes must be supplied in the following form:

Production lengths with a limit dimension of +/- 100 mm;

Cut to agreed length, with the limit values given in Table 3.

Table 3: Limits for agreed lengths

Dimensions in millimetres

Specified length L Limiting dimensions

L ˂ 1 000 ± 1.0

1 000 ≤ L ˂ 3 000 ± 1.5

3,000 ≤ L ˂ 7,000 ± 2.0

7,000 ≤ L ± 3.0

Form tolerances

4.1. Straightness

The deviation, measured at an arbitrarily selected section of 1 m length along the length of the tube, must not exceed 1.6 mm. The maximum deviation measured over the total length of the tube and expressed in millimetres may not exceed 1.6 x L (in meters).