Q235A Q345 Carbon steel welded steel pipe
Streamlined Production Process – Welded steel pipes are manufactured through a straightforward crimping and welding method, making the process easy to operate and less complex compared to seamless pipes.
High Efficiency in Manufacturing – The production of welded pipes is highly efficient, allowing for large-scale output and quicker turnaround times, which helps meet urgent market demands.
Diverse Specifications and Materials – With a broad range of sizes, types, and steel grades available, welded pipes can be customized to suit different industrial applications and performance requirements.
Lower Equipment and Investment Costs – Compared with seamless steel pipes, welded pipes require less specialized equipment and lower production investment, making them a cost-effective choice without compromising usability.
Carbon steel welded steel pipe
Welded steel pipe, also known as welded pipe, is a steel pipe made of steel plate or strip steel after crimping and welding. Welded steel pipe has simple production process, high production efficiency, many varieties and specifications, and less equipment investment, but its general strength is lower than that of seamless steel pipe.Commonly used materials for welded pipes are: Q235A, Q235C, Q235B, 16Mn, 20#, Q345, L245, L290, X42, X46, X60, X80, 0Cr13, 1Cr17, 00Cr19Ni11, 1Cr18Ni9, 0Cr18Ni11Nb, etc.
Common materials and chemical compositions of carbon steel welded pipes
Grade | Level | Chemical composition,% | Deoxygenation method | ||||
C | Mn | Si | S | P | |||
No greater than | |||||||
Q195 | - | 0.06~0.12 | 0.25~0.50 | 0.30 | 0.050 | 0.045 | F、b、Z |
Q215 | A | 0.09~0.15 | 0.25~0.55 | 0.30 | 0.050 | 0.045 | F、b、Z |
B | 0.045 | ||||||
Q235 | A | 0.14~0. 22 | 0.30~0.65 | 0.30 | 0.050 | 0.045 | F、b、Z |
B | 0.12~0.20 | 0.30~0.70 | 0.045 | ||||
C | ≤ 0.18 | 0.35~0.80 | 0.040 | 0.040 | Z | ||
D | ≤ 0.17 | 0.035 | 0.035 | TZ | |||
Q255 | A | 0.18~0.28 | 0.40~0.70 | 0.30 | 0.050 | 0.045 | F、b、Z |
B | 0.045 | ||||||
Q275 | - | 0.28~0.38 | 0.50~0.80 | 0.35 | 0.050 | 0.045 | b、Z |
Classification of welded steel pipes
Classification according to the form of weld:
Straight seam welded pipe and spiral welded pipe
Classification by production process:
Arc Welded Pipe, Electric Resistance Welded Pipe, High Frequency/Low Frequency Gas Welded Pipe, Furnace Welded Pipe
Classified by section shape:
(1) Simple section steel pipes - round steel pipes, square steel pipes, oval steel pipes, triangular steel pipes, hexagonal steel pipes, diamond steel pipes, octagonal steel pipes, semi-circular steel pipes, and others.
(2) Steel pipes with complex sections - unequal hexagonal steel pipes, five-petal plum-shaped steel pipes, double-convex steel pipes, double-concave steel pipes, melon-shaped steel pipes, conical steel pipes, corrugated steel pipes, case steel pipes, and others.
Classification by wall thickness:
Thin-walled steel pipe, thick-walled steel pipe.
Classification by use:
General welded pipe: used to transport low pressure fluids. It is mainly made of Q195A, Q215A, Q235A steel, and can also be made of other mild steels that are easy to weld.
Galvanized welded pipe: In order to improve the corrosion resistance of steel pipes, general steel pipes (black pipes) are galvanized. Galvanized steel pipes are divided into two types: hot-dip galvanizing and electro-galvanizing. The hot-dip galvanizing layer is thick and the cost of electro-galvanizing is low.
Oxygen-blown welded pipe: used as a steel-making oxygen-blown pipe, generally small-diameter welded steel pipes. Made with 08, 10, 15, 20 or Q195-Q235 steel strip. In order to prevent corrosion, some are aluminized.
Wire casing: that is, ordinary carbon steel electric welded steel pipe, used in concrete and various structural power distribution projects. The walls are thin, and most of them are used after coating or galvanizing.
Metric welded pipe: It is made by hot and cold strip welding of ordinary carbon steel, high-quality carbon steel or general low-alloy steel, or welded by hot strip and then cold drawn.
Roller tube: It is used for electric welded steel pipe of belt conveyor idler, generally made of Q215, Q235A, B steel and 20 steel. There are certain requirements for the curvature of the tube, the end face should be perpendicular to the center line, and the ovality.
Transformer tube: used to manufacture transformer radiator tubes and other heat exchangers, made of ordinary carbon steel.
Electric welding thin-walled tube: mainly used for making furniture, toys, lamps, etc.
Special-shaped pipe: square pipe, rectangular pipe, hat-shaped pipe, hollow rubber steel door and window steel pipe welded by ordinary carbon structure steel and 16Mn steel strip, mainly used for agricultural machinery parts, steel windows and doors, etc.
Spiral welded pipe: It is made by rolling a low carbon carbon structural steel or low alloy structural steel strip into a tube blank at a certain helical angle (forming angle), and then welding the pipe seams. Steel produces large diameter pipes. Spiral welded pipes are mainly used for oil and natural gas transmission pipelines, and their specifications are expressed by outer diameter * wall thickness. Spiral welded pipes are single-sided and double-sided.
In addition, there are scaffolding pipes, automobile pipes, deep well pump pipes, Mine fluid conveying welded steel pipe, low pressure fluid conveying galvanized welded steel pipe, belt conveyor idler electric welded steel pipe, etc.
