UNS Steel

UNS steel specifications stockholders and suppliers, delivering to the whole of the UK. UNS grades (Unified Numbering System) cover a wide range of steel specifications. Each grade is defined as a letter followed by five numbers.

The Unified Numbering System is a designation system widely accepted in the USA. It consists of a prefix letter and five digits designating a material composition. For example, a prefix of S indicates a stainless steel alloy, C indicates a copper, brass, or bronze alloys, T indicates a tool steel. The first 3 digits often match older 3-digit numbering systems, while the last 2 digits indicate more modern variations. For example, Copper Alloy No. 377 in the original 3-digit system became C37700 in the UNS System. The UNS is managed jointly by the ASTM International and SAE International. A UNS number alone does not constitute a full material specification because it establishes no requirements for material properties, heat treatment, form, or quality. Some common grades translate to other standards. For example UNS S17400 is ASTM grade 630, Cr-Ni 17-4PH precipitation hardening stainless steel UNS S30400 is 304, UNS S31600 is 316 UNS S31603 is 316L.

We welcome export enquiries for UNS steel grades. Contact our sales office and consult our shipping policy for further details.

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We list below our most common grades of UNS  stainless steel specifications

S31254 S30100
S32760 S31008
S31803 S30300
N08904 S30403
S17400 S30400
S42000 S31000
S41000 S31600
S44003 S31603

All our UNS stainless steel specifications and grades are available with a cast and analysis certificate, 3.1 mill certificate or a certificate of conformity. Please request when placing any orders.

All our UNS stainless steel grades are supplied in accordance with our ISO 9001:2015 registration. West Yorkshire Steel aim to satisfy the quality and delivery needs of our customers and we measure our performance by meeting customers’ requirements and work to continually improve the service that we provide. In order to achieve this, it is our policy to maintain an efficient and effective Quality Management System based upon the requirements of BS EN ISO 9001:2008. Our staff are appropriately trained in order to effectively implement the Quality Management System. The achievement of quality and continuous improvement is fundamental to all the steel products and services provided by us and are practiced by all employees as an integral part of their work.