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1.4.1. Specifications of the tubes used:
Minimum Material
Cold Drawn Seamless Carbon Steel
Minimum Yield Strength
350 N/mm2
Minimum Dimensions (Ø in mm)
45 x 2.5 or 50 x 2.0
38 x 2.5 or 40 x 2.0 (For roll cages/bars approved
prior to 1.1.95).
1.4.2. In selecting the steel, attention must be paid to
obtaining good elongation properties and adequate
weldability.
1.4.3. The tubing must be bent by a cold working
process and the centreline bend radius must be at
least three times the tube diameter. If the tubing is
ovalised during bending, the ratio of minor to major
diameter must be 0.9 or greater.

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