ISO 4038 standard is for Road vehicles -- Hydraulic braking systems impulse flare pipes, tapped holes,male fittings and hose end fittings.
International Standard IS0 4038 was prepared by Technical Committee lSO/TC 22, Road vehicles, Subcommittee SC 2, Brake systems and equipment.
This ISO 4038 International Standard specifies the essential dimensions and physical characteristics for metallic pipes, pipes with single flares, tapped holes, male fittings, and hose end fittings used in hydraulic braking systems for road vehicles.
Steel tubes shall have the following mechanical characteristics:
tensile strength: 2 290 MPa
yield point: 3 200 MPa
elongation at break 3 25 %
hardness: G 55 HR30T
The inner and outer surfaces of the tube shall be free from oxidation. The outer surface shall be protected against corrosion and shall withstand the NSS salt spray test in accordance with IS0 9227 for at least 96 h.