Square pipe factory cold formed large diameter thick wall square pipe in the construction industry is very widely used, used as roof truss, purlin, truss, rigid frame, wall frame, keel, roof board, wallboard, floor, doors and Windows and containers, pipes, cofferdam, steel pile, breakwater and so on. In recent years, the mesh shell, shelves, and single-story and multi-story houses made of section steel have also been rapidly developed. From airports to large shopping centers, from office buildings to stadiums, from conference centers to residential buildings, cold-formed large-diameter thick-walled square pipes are widely used in architectural design materials. In developed countries, the construction industry is the largest user of cold-formed square rectangular steel pipe. The consumption of cold-formed large-diameter thick wall square pipe in the construction industry accounts for more than 50% of the total cold-formed profiles used in the construction industry. From the perspective of structural mechanics and economy, the combination of cold-formed large-diameter thick wall square pipe, cold-formed section steel, and H-section steel in the construction industry is the best combination, which can realize the industrial plant and residential construction of the factory.

In Japan, 80 years ago, Japan only produced square rectangular steel pipes below 200mm×200mm and a small number of open cold-formed section steel. The columns of steel structure residential buildings in Japan all used H-section steel. After the 1984 earthquake in Sendai, Japan, through the study of the steel structure houses damaged in the Sendai earthquake, it was found that the weld between the column and beam was easy to crack, because of the limitation of the shape and structure of the H-section steel, with H-section steel and H-section steel welding, the weld was too few. Therefore, Japan revised the construction law after 84 and stipulated that the columns of steel structure residential buildings in Japan must adopt large diameter thick wall square pipes to increase the length of the weld, so as to improve the seismic resistance of the residential buildings. With the popularity of cold-formed large diameter thick wall square pipe in the application of building steel structures, the production specifications of cold-formed large diameter thick wall square pipe are also increasing. At present, the maximum specification of large diameter thick wall square pipe has reached 550mm×550mm, and the maximum wall thickness of the generous pipe is 25mm. In 2002, the total output of large-diameter cold-formed square pipe for steel structures in Japan reached 2 million t. At present, the steel pipe with the largest demand in the market is 200mm×200mm ~ 400mm×400mm. The cold-formed large-diameter thick-wall square pipe of these specifications covers more than 80% of the total square and rectangular steel pipe used in steel structures in Japan, and the products of other specifications account for less than 10% of the market share.

In the United States, according to the relevant survey data, the amount of cold-formed square rectangular steel pipe and hot-rolled H section in the construction industry is about 1:1 relationship, in the 1990s, the proportion of cold-formed steel used in building steel structures even exceeds the amount of hot-rolled H section. Among them, welded pipe of cold-formed structure (including square rectangular pipe and original pipe) accounts for about 25% of the steel used in building steel structures, and the proportion of cold-formed steel of various openings in the steel used in building steel structures is more than 20%.

Cangzhou Shenlong Pipe Factory specializes in the production and operation of large diameter thick wall square pipe and various square pipe, steel pipe spot specifications are as follows:

Square pipe: 10*10-100*100*0.5-10mm 120*120-200*200*4-12mm 220*220-600*600*5-25mm

Rectangular tube: 10*15-150*50*0.5-12mm 160*80-250*150*4-14mm 280*150-600*550*5-25mm 350*250*8-30mm-800*600*35mm

1. The above square pipe can be made into straight slit square moment and seamless square pipe, special specifications can be customized for processing.

The main application fields are: machinery manufacturing, construction industry, metallurgical industry, agricultural vehicles, agricultural greenhouses, automobile industry, railway, highway guardrail, container skeleton, furniture, decoration, and steel structure construction