IS 6603:2024 — BIS Certification for Stainless Steel Semi-Finished Products, Bars, Wire Rods & Bright Bars

IS 6603:2024 is an Indian Standard published by the Bureau of Indian Standards (BIS) in April 2024 under ICS 77.140.20. It supersedes both IS 6603:2001 (Stainless Steel Bars and Flats) and IS 6527:1995 (Stainless Steel Wire Rod), consolidating coverage into a single, modernised document.

The standard specifies technical delivery conditions for semi-finished products, hot-formed and cold-finished bars, wire rods, and bright bars in various corrosion-resisting stainless steel grades. BIS drew assistance from ISO 16143 (Part 2):2014 and ISO 16143 (Part 4):2023, aligning India’s requirements with current international practices.

Under the Steel and Steel Products (Quality Control) Order, the Ministry of Steel has progressively brought stainless steel long products within the mandatory BIS certification framework. Manufacturers, importers, and suppliers must hold a valid BIS licence — bearing the ISI Mark — before placing certified product on the Indian market.

Non-compliance carries serious consequences: products without the Standard Mark cannot be sold, and violations attract action under the Bureau of Indian Standards Act, 2016. As IS 6603:2024 supersedes the 2001 edition, licence-holders operating under the older standard must align with the updated requirements.

Expanded scope

The scope now explicitly includes semi-finished products (blooms, billets from continuous casting or ingot rolling), wire rods, and bright bars alongside the bars and flats covered by the earlier edition.

Revised grade portfolio

Several grades have been added, removed, or redesignated — including the removal of X07Cr18Ni9 and X10Cr17Mn6Ni4N, redesignation of X07Cr17 → X04Cr17 and X12Cr12 → X12Cr13, and new duplex and high-alloy austenitic grades to reflect current market demand.

Surface finish and dimensional tolerances

Process routes and surface finish codes (1U, 1C, 1E, 1D, 1G, 1P, 2H, 2D, 2B, 2G, 2P) are now formally defined in Table 1. Dimensional tolerances for special finishes extend to nominal sizes up to 3,150 mm via IT tolerance grades specified in Table 36.

Freedom from defects criteria

Maximum permissible depths of acceptable discontinuities have been updated (Table 2) with distinct limits by finish condition and product form — grades 1G/2B/2G/2P rounds must be technically defect-free by manufacture.

Each bar or flat over 50 mm in diameter must be legibly stamped, stencilled, or labelled with the cast number and type of steel. Bars and flats up to 50 mm must be bundled with a tag bearing the cast number and steel type. Each coil of wire rod must carry the manufacturer’s name or trade mark, cast number, and steel designation.

For BIS-certified product, the ISI Mark (BIS logo with IS number and CM/L licence number) must appear on each bundle tag, coil tag, or on the bar itself. The marking method must be durable enough to remain legible through storage and transport.