What Is a Concentric Contraction?

The large and small heads of a circle centered on a straight line are called concentric large and small heads. The forming process usually used is reduced diameter pressing, expanded diameter pressing or reduced diameter plus expanded diameter pressing. For some specifications of reducers, stamping can also be used.

Concentric head

Center of the circle on a straight line

concentric reducer

concentric

(1) Concentricity under internal pressure

1. Divided by material:

Carbon steel: ASTM / ASME A234 WPB,

There are two main international pipe flange standards, namely the European pipe flange system represented by German DIN (including the former Soviet Union) and the American pipe flange system represented by American ANSI pipe flange. In addition, there are Japanese JIS pipe flanges, but they are generally only used for public works in petrochemical plants, and have a small international impact. The pipe flanges of various countries are introduced below:

1. European system pipe flanges represented by Germany and the former Soviet Union

2, American system pipe flange standards, represented by ANSI B16.5 and ANSI B 16.47

3, British and French pipe flange standards, each country has two sleeve flange standards.

In summary, the internationally accepted standard for pipe flanges can be summarized as two different and non-interchangeable pipe flange systems: one is the European pipe flange system represented by Germany; the other is the United States. American tube flange system.

IOS7005-1 is a standard promulgated by the International Organization for Standardization in 1992. This standard is actually a pipe flange standard combining two sets of pipe flanges from the United States and Germany.