2021 New Style Large Diameter Steel Strip Pipe - 20# fluid seamless steel pipe manufacturer – Weichuan

Fluid pipe is a kind of steel pipe with hollow section and no weld from beginning to end. Steel pipe has hollow section, which is widely used as a pipe for conveying fluid, oil, natural gas, gas, water and some solid materials. Compared with solid steel such as round steel, steel pipe has the same bending and torsional strength and light weight. It is an economic section steel. It is widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipe, automobile transmission shaft, bicycle frame and steel scaffold used in construction.

Fluid pipe is a pipe specially used to transport media with fluid properties.

In addition to liquid media such as water, oil and solution, solid media such as cement, grain and pulverized coal can also flow under certain conditions.

Fluid pipes can be made of steel, non-ferrous metals such as copper and titanium, and even non-metallic materials such as plastics.

The fluid pipe must have hollow section, but it can also be square, triangular or any other shape. Some equipment must use rectangular pipe due to limited conditions, but the vast majority still use circular pipe. The circular tube has the smallest circumference / area ratio in all geometric sections, that is, the largest inner section can be obtained under the condition of using the same amount of materials.

Steel pipe is widely used in fluid transportation in modern society because of its low cost and high strength. According to its production process, steel pipes are divided into seamless steel pipes and welded pipes. Welded pipes are also divided into high-frequency straight seam welded pipes (ERW), spiral welded pipes (SSAW), submerged arc welded pipes (UOE), etc. In the past, seamless steel pipes were traditionally used for fluid pipes. With the development and progress of material science, forming technology and unit equipment, welded pipes have been greatly developed. Welded pipe has the advantages of better wall thickness uniformity, high precision, less energy consumption and high production efficiency than seamless pipe. In the past, almost 100% of seamless pipe was used for oil and gas transmission pipe (API standard). Today, more than 95% of them have been replaced by welded pipe in the United States, Japan and European developed countries.

① Generally, the service temperature of boiler tubes is below 450 ℃, and domestic tubes are mainly made of No. 10 and No. 20 carbon structure steel hot-rolled tubes or cold drawn tubes.

② High pressure boiler tubes are often in high temperature and high pressure conditions. The tubes will be oxidized and corroded under the action of high temperature flue gas and steam. The steel pipe is required to have high lasting strength, high anti-oxidation and corrosion performance and good structural stability.