Common knowledge of spiral submerged arc welded steel pipe

With the rapid development of high quality strip continuous rolling production and the progress of welding and inspection technology, the quality of weld seam is continuously improving, and the variety and specification of welded steel pipe is increasing. In more and more fields, welded steel pipe of seamless steel pipe is replaced by straight welded pipe and spiral welded pipe according to the form of weld seam.

Longitudinal welded pipe has the advantages of simple production process, high production efficiency, low cost and rapid development. The strength of spiral welded pipe is generally higher than that of straight welded pipe. It can produce welded pipe with bigger diameter with narrower blank, and welded pipe with different diameter can also be produced with blank of the same width. However, compared with the straight seam pipe of the same length, the length of the weld increases by 30-100%, and the production speed is lower.

Therefore, most of the smaller diameter welded pipes are welded by straight seam welding, while the larger diameter welded pipes are mostly welded by spiral welding.

1. Spiral submerged arc welded steel pipe (SY5037-2000) for low-pressure fluid transportation is a submerged arc welded steel pipe for general low-pressure fluid transportation, such as water, gas, air and steam, which is manufactured by double-sided automatic submerged arc welding or single-sided welding, using hot rolled steel strip as billet and spiral forming at normal temperature.

2. Welded steel pipes for low pressure fluid transportation (GB/T3092-1993) are also known as general welded pipes, commonly known as black pipes. It is a welded steel pipe used for conveying water, gas, air, oil, heating steam and other general low pressure fluids and other purposes. The wall thickness of steel pipe can be divided into ordinary steel pipe and thickened steel pipe, and the nozzle end can be divided into non-threaded steel pipe (smooth pipe) and threaded steel pipe. The specification of steel pipe is expressed by nominal diameter (mm), which is the approximate value of inner diameter. It is customarily expressed in inches, such as 11/2, etc. In addition to directly conveying fluids, welded steel pipes for low-pressure fluid conveying are also widely used as raw pipes for galvanized welded steel pipes for low-pressure fluid conveying.

3. Common carbon steel wire bushing (GB3640-88) is a steel pipe used to protect electric wires in industrial and civil buildings, installation machinery and equipment and other electrical installation projects.

4. Spiral seam high frequency welded steel pipes (SY5039-83) for low-pressure fluid transportation are usually formed by hot-rolled steel strip coils and spirally formed at normal temperature. High frequency lap welding method is used to weld spiral seam high frequency welded steel pipes for general low-pressure fluid transportation.

5. Galvanized welded steel pipes for low pressure fluid transportation (GB/T3091-1993) are also called galvanized welded steel pipes, commonly known as white pipes. It is a hot dip galvanized welding (furnace welding or electric welding) steel pipe used for conveying water, gas, air oil, heating steam, warm water and other generally low pressure fluids or other purposes. The wall thickness of steel pipe can be divided into common galvanized steel pipe and thick galvanized steel pipe, and the end of pipe can be divided into non-threaded galvanized steel pipe and threaded galvanized steel pipe. The specification of steel pipe is expressed by nominal diameter (mm), which is the approximate value of inner diameter. It is customarily expressed in inches, such as 11/2, etc.

6. Spiral welded steel pipe for piles (SY5040-2000) is made of hot rolled steel strip coil as billet, often spirally formed at high temperature, and is welded by double-sided submerged arc welding or high frequency welding. It is used for steel pipe for foundation piles such as civil building structures, wharfs and bridges.

7. Longitudinal welded steel pipe (YB242-63) is a steel pipe with longitudinal parallel weld and steel pipe. Usually it is divided into metric welded steel pipe, welded thin-walled pipe, transformer cooling oil pipe and so on.

8. Spiral submerged arc welded pipe (SY5036-83) for pressure fluid transportation is a kind of spiral welded pipe with hot rolled steel strip coil as billet, which is spirally formed at normal temperature and welded by double-sided submerged arc welding. Steel pipe has strong pressure bearing capacity and good welding performance. It is safe and reliable to use after various strict scientific tests and tests. The steel pipe has large diameter, high conveying efficiency and saves investment in laying pipelines. It is mainly used for pipelines to transport oil and natural gas.

9. The SY5038-83 spiral seam high frequency welded steel pipe for pressure fluid conveying is a high frequency spiral seam high frequency welded steel pipe for pressure fluid conveying, which is formed by hot rolled steel strip coil and is welded by high frequency lap welding. The steel pipe has strong bearing capacity, good plasticity, and is easy to be welded and processed. Through various strict and scientific tests and tests, it is safe and reliable to use, large diameter of steel pipe, high transportation efficiency, and can save the investment of laying pipelines. It is mainly used for laying pipelines for oil and natural gas transportation.