Processing technology and inspection steps of straight seam steel pipes

In the production process of straight seam steel pipe, the processing method will have a lot of impact on it. So what are the processing methods for straight seam steel pipes? The staff of the manufacturer will introduce to you the main methods. By using the repeated impact of the forging hammer, the shape and size of the blank can be changed to meet the production requirements. This is the forging steel processing method. Applying pressure through a press has the same effect. Extrusion is also a very important method for making straight seam steel pipes. It is a method of placing steel in a closed extrusion container for compression so that the product will obtain the desired size and shape when it comes out of the mold. The rolling method is also commonly used, which changes the shape through the gap between the rolls. Drawn steel is often used for cold working, which increases length and reduces cross-sectional area by applying tension to the metal.

Processing technology of straight seam steel pipe:

1. Forging steel: A pressure processing method that uses the reciprocating impact of a forging hammer or the pressure of a press to change the blank into the shape and size we require.

2. Extrusion: It is a steel processing method in which metal is placed in a closed extrusion cylinder and pressure is applied on one end to extrude the metal from a prescribed die hole to obtain a finished product of the same shape and size. It is mostly used for the production of non-ferrous metals. Material steel.

3. Rolling: A pressure processing method in which the steel metal blank passes through the gap (of various shapes) between a pair of rotating rollers. Due to the compression of the rollers, the cross-section of the material is reduced and the length is increased.

4. Drawing steel: It is a processing method that draws the rolled metal blank (shaped, tube, product, etc.) through the die hole to reduce the cross-section and increase the length. Most of them are used for cold processing.

Inspection steps for straight seam steel pipes:

1. Straight seam steel pipes should be submitted for acceptance in batches, and the batching rules should comply with the provisions of the corresponding product standards.

2. The inspection items, sampling quantity, sampling locations, and test methods of straight seam steel pipes shall be by the provisions of the corresponding product standards. With the consent of the purchaser, hot-rolled seamless straight-seam steel pipes can be sampled in batches according to the rolling root number.

3. When the straight-seam steel pipe test results show that a certain item does not meet the requirements of the product standard, the unqualified ones should be singled out, and double the number of samples should be taken from the same batch of straight-seam steel pipes to test the unqualified items. recheck. If the re-inspection results (including any indicator required for the test of the project) are unqualified, the batch of straight seam steel pipes shall not be delivered. If the following inspection items fail the initial inspection, re-inspection is not allowed: 1) White spots in the low-magnification tissue; 2) Microstructure.

4. For straight-seam steel pipes with unqualified re-inspection results (including items whose microstructure is unqualified in the initial inspection and re-inspection is not allowed), the supplier may submit them for acceptance one by one; or re-heat treatment (the number of re-heat treatments shall not exceed two times) ), submit a new batch for acceptance.

5. If there are no special provisions in product standards, the chemical composition of straight seam steel pipes shall be inspected according to the melting composition.

Straight seam steel pipe is not only used to transport fluids and powdery solids, exchange heat energy, and manufacture mechanical parts and containers, it is also an economical steel. Using straight seam steel pipes to manufacture building structural grids, pillars, and mechanical supports can reduce weight, save 20 to 40% of metal, and enable factory-like mechanized construction. Using straight seam steel pipes to manufacture road bridges can not only save steel and simplify construction but also greatly reduce the area of protective coating, saving investment and maintenance costs. Therefore, any other type of steel cannot replace straight seam steel pipes, but straight seam steel pipes can replace some profiles and bars. From people's daily utensils, furniture, water supply and drainage, air supply, ventilation, and heating facilities to the manufacturing of various agricultural machinery and equipment, the development of underground resources, and the use of guns, bullets, missiles, rockets, etc., straight seam steel pipes are inseparable.

Because straight-seam steel pipes are inseparable from human life and production activities, the production technology of the straight-seam steel pipe industry not only develops rapidly but also introduces new ones. Straight-seam steel pipe production occupies an irreplaceable position in the steel industry. The development of straight seam steel pipe production technology began in the construction manufacturing industry. The development of oil in the early 19th century, the manufacturing of ships, boilers, and aircraft during the two world wars, the manufacturing of thermal power boilers after the First World War, the development of the chemical industry, and the drilling and transportation of petroleum gas all strongly promoted the direct The development of the seam steel pipe industry in terms of variety, output, and quality.