Seamless square rectangular pipe is a kind of long steel with a hollow section and no joints around the perimeter. The tube is hollow, with a set cross-sectional area, a large number of pipelines used for conveying fluids, such as pipelines transporting oil, natural gas, gas, water and some solid materials, etc., the ring section is under internal or external radial pressure, the force is more uniform, therefore, the vast majority of steel pipes are round pipes. However, the round pipe also has certain limitations, such as under the condition of plane bending, the round pipe is not as strong as the square and rectangular pipe bending strength, and some agricultural machinery skeletons, steel and wood furniture are commonly used square and rectangular pipes.

Enforce standards:

GB/T3094-2000 (national standard) cold-pressed shaped rectangular tube

GB/T6728-2002 (National standard) cold formed hollow section steel for structure

ASTM A500 (American Standard) Welded rectangular tubes and seamless rectangular tubes with carbon steel cold formed round and shaped sections for construction

EN10219-1-2006(European standard) non-alloy and fine grain cold formed welded hollow structure profiles

JIS G 3466 (day standard) angular rectangular tube for general construction