This standard (Part 4) is relevant to stainless steels specified in the standard, commonly utilized in the cold drawn state as wire with a circular cross-section, up to 10 mm in diameter. It's intended for crafting springs and spring components exposed to corrosive conditions and occasionally slightly higher temperatures.

The stainless steels addressed in this standard possess special corrosion resistance and are predominantly austenitic, containing chromium levels exceeding 12%. These steels are cold drawn to achieve spring-hardness.

The stainless-steel wire will be categorized into three grades: Grade 1, Grade 2, and Grade 3.

The material supply must adhere to the relevant standard's general requirements. Manufacturers have discretion over the processes used in manufacturing steel and stainless spring steel wire. The wire's surface should be smooth and devoid of defects like grooves, pits, die-marks, and other detrimental flaws impacting its application.

The tolerance on wire diameter must align with the specifications outlined in the standard. The variance between maximum and minimum wire diameters at the same cross-section should not surpass 50% of the total permissible deviation specified in the standard. The wire may be coated or uncoated, and its mechanical properties must meet the standard requirements.

TESTS

The subsequent test must be conducted for Stainless Steel Wire.

• Tensile test

• Wrapping test

• Reverse torsion test

• Cast of the wire

• Bend test

• Coiling test

PACKING AND MARKING

The packaging should ensure sufficient protection against mechanical damage and contamination during transportation. Each coil of wire and bundle of straightened and cut lengths must be clearly marked with the supplier's name, wire grade, wire diameter, surface finish, coil mass, cast or batch number, and supply date. Optionally, the standard mark (ISI Mark) can also be applied to the material.

To utilize the standard mark (ISI Mark), the manufacturer needs to obtain a BIS license from the Bureau of Indian Standards. This license is granted after a thorough assessment of manufacturing infrastructure, production processes, and quality control and testing capabilities conducted during an on-site visit to the manufacturing premises.

PROCESS FOR BIS ISI MARK CERTIFICATION