Grading Of Stainless Steels – An Overview

By Author: Bluesteel Services
Total Articles: 25
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Stainless steels have been divided into categories based on their structure at room temperature. Properties of the steels are also affected by the characteristics of the alloying elements. You need to factor in the grade of the steel before placing your order with a supplier.

Stainless steel tubes and pipes have some unique properties which make them an integral part of several industrial operations. These are:

• Corrosion resistance
• Retaining of strength even at high temperatures
• Superb fatigue and impact resistance
• Smooth and minimally porous surface
• Bright aesthetic appearance
• Easily machined, welded, formed and fabricated
• High shock resistance at low and high temperatures
• Yielding durable long-life products

There are a large number of stainless steel grades with widely varying compositions. The structure of stainless steel has a decisive effect on properties. This gives them standardization in terms of composition and properties.

Stainless steels can broadly be categorized into six groups – ferritic, ferritic-austenitic, ...
... martensitic, martensitic-austenitic, austenitic and precipitation hardening steels.

Martensitic and martensitic-austenitic stainless steels can be hardened that means their properties can be modified via heat treatment. The precipitation hardening steels may also be hardened by heat treatment. The procedure of hardening includes special heat treatment or thermo-mechanical treatment sequences including a final precipitation hardening and ageing step. Ferritic, ferritic-austenitic and austenitic are not hardened. Only one category of stainless steels – austenitic steels – is non-magnetic. All the other steels are magnetic.

The alloying elements also affect the properties of the steel. The combined effect of all the alloying elements along with the impurities determines the property profile of a steel grade.

Stainless steel products used for various industrial purposes are the pipes, forged flanges, tubes and tubing pup joints. The pup joints are used to adjust the height of the strings in the tubing. API stainless steel products fit in for heavy pressure applications, while welded stainless steel pipes are better for intricate pipe network.

For food processing, pharmaceutical production, conveyance of gases in the liquid form, processing of solution of semi solids and a number of other industrial procedures, API 5CT stainless steel pipes and tubes are preferred as they have good cryogenic strength, good corrosion resistance, excellent surface finish, ductility, property stability in service, and resistance to abrasion, oxidation and sulfidation.

Product line of a leading supplier of stainless steel industrial products such as Blue Steel Services may include Steel Fire Sprinkler Pipe in accordance with ASTM A 53 A, ASTM A 135/795; ASTM A53 Grade A & B, A500B and A252 Pipes; flat rolled, hot and cold rolled steel coils; etc.

Collaborate with a supplier that you can rely on for product quality. They must be people who have earned reputation for the quality of products over time and have a gamut of products at hand. Along with a large inventory, such suppliers have long standing relationships with logistics providers that enable them to deliver products in timely manner.

With them, stainless steel pipe and other products are available in varied sizes, shapes and specifications, so you can find steel pipes that perfectly suit your requirements. They would supply products in accordance with global standards. The suppliers would ascertain tight configuration and zero defects in the product line with a series of quality assurance tests. It is important that you source quality stainless steels as the viability of operations depends on the industrial components used.

Author of this article is associated with Blue Steel Services LLC, which is engaged in OCTG sales, steel coils, electrical conduits, water well casing and pipes.