Application of stainless steel

Hardness

Stainless steel tube commonly used brinell, Rockwell, Vickers three hardness indicators to measure its hardness.

Brinell hardness

In the stainless steel tube standard, brinell hardness is the most widely used, often to indentation diameter to express the hardness of the material, both intuitive and convenient. However, it is not suitable for hard or thin steel pipes.

Rockwell hardness

The Rockwell hardness test of stainless steel tube is the same as brinell hardness test, which is the indentation test method. The difference is that it measures the depth of the indentation. Rockwell hardness test is a widely used method at present, among which HRC is second only to Brinell hardness HB in steel pipe standard. Rockwell hardness can be applied to determine from very soft to very hard metal materials, it makes up for the Brinell method is not, is simpler than brinell method, can be directly from the hardness machine dial read hardness value. However, due to the small indentation, the hardness value is not as accurate as buchwald method.

Vickers hardness

Stainless steel tube Vickers hardness test is also an indentation test method, can be used to determine the hardness of very thin metal materials and surface layer. It has the main advantages of Brinell and Rockwell methods and overcomes their basic disadvantages, but it is not as simple as Rockwell methods and is seldom used in steel pipe standards.

Hardness testing

The inner diameter of stainless steel pipe is more than 6.0mm, and the wall thickness is less than 13mm. The annealed stainless steel pipe can be tested by W-B75 Type Wechsler hardness tester. It is very fast and simple, and suitable for rapid and nondestructive inspection of stainless steel pipe. Stainless steel pipe inner diameter is greater than 30mm, wall thickness is greater than 1.2mm stainless steel pipe, rockwell hardness tester, test HRB, HRC hardness. Stainless steel tubes with inner diameter greater than 30mm and wall thickness less than 1.2mm were tested for HRT or HRN hardness by surface Rockwell hardness tester. For stainless steel pipes with inner diameter less than 0mm and greater than 4.8mm, rockwell hardness tester is used to test HR15T hardness. When the inner diameter of stainless steel pipe is greater than 26mm, you can also use Rockwell or surface Rockwell hardness tester to test the hardness of the inner wall of the pipe.

The development of stainless steel

All the two ends of the opening and hollow section, and its length and section circumference of the larger steel, can be called steel pipe. When the length and section circumference of the comparison is small, can be called pipe section or pipe fittings, they all belong to the category of pipe products.

For more than 60 years, architects have been using stainless steel to construct cost-effective permanent structures. Many existing buildings amply illustrate the correctness of this choice. Some are very ornamental, such as the Chrysler Building in New York City. But in many other applications, stainless steel plays a less dramatic but important role in the aesthetics and performance of buildings. Stainless steel, for example, is the material of choice for designers building sidewalks in high-traffic areas because it is more resistant to abrasion and creasing than other metals of the same thickness.

Stainless steel has been used as a structural material for the construction of new buildings and restoration of historic sites for more than 70 years. Early designs were based on basic principles of computation. Today, design specifications, such as the ANSI/ASCE-8-90 "Design Code for Cold-formed Stainless Steel Structural Parts" standard and the "Structural Stainless Steel Design Manual" published jointly by NiDI and Euro Inox, have simplified the design of long-life, well-maintained structural parts for buildings.

Stainless steel export is an important part of China's export economy, it plays an important role in stimulating China's economic growth, but from the current situation of China's stainless steel foreign trade, China's stainless steel export encountered greater resistance.

Since last year, overseas frequently came to the stainless steel casting products in China "double reverse" message, it has a great influence for the stainless steel casting industry in China, and exports are a good portion of the stainless steel industry development in our country, in the development of the industry has a huge market share, in the face of the economic downturn, the development speed slow, Stainless steel industry development in our country should continuously improve product quality, better the development of overseas trade and against trade protectionism, the products and environmental protection, energy resources, humanities environment, enhance the competitiveness of the stainless steel products, only in this way can the indefectible position in the foreign trade.