Welded steel pipe, also known as welded pipes, is made of steel or steel strip after crimping formed welded steel pipe. Welded steel pipe production process is simple, high production efficiency, variety specifications, equipment, less capital, but the general strength of less than seamless steel tube. Since the 1930s, with the rapid development of high quality strip continuous rolling and the progress of welding and inspection technology, the quality of welding has been improved continuously, the variety specification of welded steel pipe is increasing, and the seamless steel pipe is replaced in more and more fields.
Welded steel pipe is divided into straight seam welded pipe and spiral welded pipe in the form of weld seam. Straight seam welded pipe production process simple, high production efficiency, low cost, rapid development. The strength of spiral welded pipe is generally higher than that of straight seam welded pipe, it can produce welded pipe with larger pipe diameter with narrower billet, and can produce welded pipe with different pipe diameter with same width.
However, the weld length increases 30~100% and the production speed is lower compared with the straight seam tube of the same length.
As a result, the smaller-caliber welded pipe mostly uses the straight seam welding, the large diameter welded pipe mostly uses the spiral welding. 1. Low-pressure fluid conveying welded steel pipe (gb/t3092-1993) also known as General welded pipe, commonly known as the clarinet. is used for conveying water, gas, air, oil and heating steam and other general low pressure fluids and other uses of welded steel pipe. The pipe wall thickness is divided into ordinary steel pipe and thickened steel pipe, and the nozzle end is divided into no threaded pipe (light tube) and ribbed pipe. The specification of the steel pipe is indicated by the nominal diameter (mm), the nominal diameter is the approximate value of the inner diameter. Customarily used in inches, such as 11/2.
Low-pressure fluid transport welded steel pipe, in addition to directly used for conveying fluids, but also a large number of low pressure fluid transport with galvanized welded steel pipe original pipe. 2. Low-pressure fluid conveying galvanized steel pipe (gb/t3091-1993) also known as galvanized welded steel pipe, commonly known as white tube. is used for conveying water, gas, air oil and heating steam, warm water and other general low pressure fluids or other uses of hot dip galvanized welding (furnace welding or welding) steel pipe. The wall thickness of steel pipe is divided into ordinary galvanized steel pipe and thickened galvanized steel pipe, and the nozzle end is divided into non threaded galvanized steel pipe and ribbed galvanized steel pipe. The specification of the steel pipe is indicated by the nominal diameter (mm), the nominal diameter is the approximate value of the inner diameter.
Customarily used in inches, such as 11/2.
3. Ordinary carbon steel wire casing (gb3640-88) is the industrial and civil construction, installation machinery and equipment, such as electrical installation works for the protection of wire steel pipe. 4. Straight Seam welded steel pipe (yb242-63) is the weld and steel pipe longitudinal parallel.
Usually divided into metric welded steel pipe, welded thin-walled tube, transformer cooling tubing and so on. 5. The spiral seam submerged arc welded pipe (sy5036-83) which is used for pressure fluid conveying is made of hot rolled steel strip coil as tube billet, constant temperature spiral forming, and welded by two-sided submerged arc welding, which is used for the spiral seam pipe of pressure fluid conveying. Steel pipe pressure capacity, good welding performance, after a variety of rigorous scientific testing and testing, the use of safe and reliable. Pipe diameter is large, conveying efficiency is high, and can save the investment of laying pipelines.
Mainly used for transporting oil and gas pipelines. 6. Pressure fluid conveying spiral seam high-frequency welded steel pipe (sy5038-83) is a hot-rolled steel strip coil for tube billet, often temperature spiral molding, the use of high-frequency lap welding welding, for the pressure of fluid transmission spiral seam high-frequency welded steel pipe. Steel pipe pressure capacity, good plasticity, easy to weld and process molding; Through a variety of rigorous and scientific testing and testing, the use of safe and reliable, pipe diameter, high transmission efficiency, and can save the investment of laying pipelines.
It is mainly used for laying pipelines for transporting oil, natural gas and so on.
7. The general low-pressure fluid transportation uses the spiral seam submerged arc welding pipe (sy5037-83) to take the hot-rolled steel strip coil as the tube billet, constant temperature spiral molding, the use of double-sided automatic submerged arc welding or single-sided welding method for water, gas, air and steam, such as general low pressure fluid conveying submerged arc welding pipe.
8. The general low-pressure fluid transportation uses the spiral seam high frequency welding pipe (sy5039-83) is takes the hot-rolled steel strip coil as the tube billet, the constant temperature spiral molding, uses the high frequency lap welding method welding for the general low pressure fluid transportation uses the spiral seam high-frequency welding steel pipe. 9. Pile Spiral Welded pipe (sy5040-83) is a hot-rolled steel strip coil for tube billet, often temperature spiral molding, using double-sided submerged arc welding or high-frequency welding made, used for civil construction structures, piers, bridges and other foundation piles of steel pipe.