What is the absolute roughness of hot rolled seamless steel pipes

Generally, the hot drawing tube adopts F grade, Ra=; The hot-rolled pipe adopts E grade, Ra=, and the allowable deviation Ra+25%.

Seamless steel pipe. Seamless steel pipes have a hollow cross-section, and are widely used as pipelines for transporting fluids, such as pipelines for transporting oil, natural gas, gas, water and some solid materials. Steel pipes and round bars.

Compared with solid steel, when the bending and torsional strength is the same, the weight is lighter, and it is an economical cross-section steel, which is widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipes, automobile drive shafts, bicycle racks and steel scaffolding used in building construction.

Steel pipes are used to manufacture annular parts, which can improve the utilization rate of materials, simplify the manufacturing process, save materials and processing man-hours, and have been widely used in steel pipes.

Our company has its own professional subordinate precision seamless pipe factory is a set of perforation, hot rolling, cold drawing sales in one, the implementation of diversified business strategy, our company covers an area of 100 acres, with more than 300 employees (including 10 senior engineers, 30 professional technicians, 5 experts), two hot rolling units, 6 cold drawing units, 2 perennial production of 25-133 2-20 precision seamless tubes, precision bright tubes!

It depends on the accuracy of the rolling mill, as long as there is no oxide scale, it is qualified.

Generally, the cold drawn tube adopts F grade, Ra=; The cold-rolled pipe adopts E grade, Ra=, and the allowable deviation is Ra+25%.

Seamless steel pipe: Seamless steel pipe has a hollow cross-section, which is widely used as a pipeline for transporting fluids, such as pipelines for transporting oil, natural gas, gas, water and some solid materials. Compared with solid steel such as round steel, steel pipe is lighter in weight when the bending and torsional strength is the same, and it is an economic cross-section steel, which is widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipe, automobile drive shaft, bicycle rack and steel scaffolding used in building construction, etc., to manufacture annular parts with steel pipes, which can improve material utilization, simplify the manufacturing process, save materials and processing man-hours, and has been widely used to manufacture.

Hot Rolled Pipe:

Cold Drawn Tube: Normal annealed tube, left and right.

Generally, the bright tube that is not annealed is on the left and right, and the bright tube with good processing technology is on.

It is used in the national standard pipeline transportation.

Hello, seamless steel pipes are divided into hot-rolled pipes and cold-drawn (rolled) pipes according to the manufacturing method. The nominal diameter of cold-drawn (rolled) pipe is 200 mm, and the nominal diameter of hot rolled pipe is 600 mm. In pipeline engineering, when the pipe diameter is more than 57mm, hot-rolled pipes are often used, and cold-drawn (rolled) pipes are commonly used when the pipe diameter is less than 57mm.

There are three types of seamless steel pipes commonly used in pipeline engineering: General seamless steel pipe General seamless steel pipe is referred to as seamless steel pipe, which is made of ordinary carbon steel, high-quality carbon steel, ordinary low-alloy steel and alloy structural steel, and is used to make liquid pipelines or make structures and parts in virtual acres. Seamless steel pipes are supplied according to the outer diameter and wall thickness, and there are multiple wall thicknesses under the same outer diameter, which can withstand a large pressure range in the brother's reputation.

Usually the length of the steel pipe, the hot-rolled pipe is, and the cold-drawn (rolled) pipe is. Seamless steel tubes for low and medium pressure boilers Seamless steel tubes for low and medium pressure boilers are made of No. 10 and No. 20 high-quality carbon steel, and the working temperature is envy. Hope it helps.

The original state of the steel, that is, the delivery state of the steel pipe, can be divided into (code in parentheses): cold worked hard (BK), cold worked soft (BKW), stress relief annealing after cold working (BKS), tempering (GBK), normalizing (NBK). The commonly used state is annealed, which is convenient for subsequent processing.

The properties and general applicability of steel pipes in various states are as follows:

Cold-worked hard (BK) steel pipes are produced by cold working of the finished pass with normal or maximum deformation, without heat treatment, and have the highest dimensional accuracy and the highest tensile strength and the lowest elongation coefficient. It is generally used in the manufacture of motorcycle parts, such as shock absorber struts.

Cold-worked soft (BKW) steel pipes are produced by cold working of the finished pass with a small amount of deformation, without heat treatment, with the highest dimensional accuracy and high tensile strength, a certain elongation coefficient (10-15%). It is generally used in the manufacture of auto parts.

Stress-relieving annealing (BKS) steel pipes after cold working are subjected to low temperature and rapid heat treatment after cold working, which has high dimensional accuracy, slightly higher tensile strength, and a certain elongation coefficient (more than 15%). It is generally used to manufacture various mechanical parts.

Annealed (GBK) steel pipes are subjected to normal and complete heat treatment after cold working, with normal dimensional accuracy and normal tensile strength, elongation coefficient (more than 20%). It is the most commonly used state and has the widest range of applications.