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Discussion and Analysis on the connection of pipe fittings
Time：2020-01-21 12:01:35
General seamless steel pipe is called seamless steel pipe for short. It is made of ordinary carbon steel, high-quality carbon steel, ordinary low-alloy steel and alloy structural steel. It is used to make liquid pipelines or structures and parts.
Seamless steel pipe is divided into hot rolled pipe and cold drawn (rolled) pipe according to the manufacturing method. The maximum nominal diameter of cold drawn (rolled) pipe is 200mm, and the maximum nominal diameter of hot-rolled pipe is 600mm. In pipeline engineering, when the pipe diameter is more than 57mm, hot-rolled pipe is often used, and when the pipe diameter is less than 57mm, cold drawn (rolled) pipe is often used. There are three kinds of seamless steel pipes commonly used in pipeline engineering:
Spiral seam high-frequency welded steel pipe spiral seam high-frequency welded steel pipe, there is no same product scale, generally using ordinary carbon steel Q235, q235f and other steel products.
Seamless steel pipe is supplied according to outer diameter and wall thickness. There are many kinds of wall thickness under the same outer diameter, and the pressure range is large. Generally, the length of steel pipe is 3-12.5m for hot-rolled pipe and 1.5m-9m for cold drawn (rolled) pipe. The inner and outer walls coated with a zinc protective layer are about 3% - 6% heavier than the non galvanized ones. According to the different wall thickness of the pipe, it can be divided into thin-walled pipe, common pipe and thickened pipe. The thin-walled tube is not suitable for conveying medium and can be used as casing. The straight seam rolled electric welded steel pipe can be divided into the electric welded steel pipe and the straight seam rolled welded steel pipe made of steel plate in blocks on site. It can be made into several pipe wall thicknesses.
Spiral seam automatic submerged arc welded steel pipe can be divided into class a pipe and class B pipe according to the pressure of conveying medium. Class a pipes are generally made of ordinary carbon steel Q235, q235f and ordinary Low Alloy Structural Steel 16Mn by welding. Class B pipes are made of Q235, q235f, Q195 and other steels by welding, which are used as low pressure fluid conveying pipes. Welded steel pipe for low-pressure fluid transmission is made of carbon mild steel, which is the most commonly used small-diameter pipe in pipeline engineering. It can be used to transport water, gas, steam and other media. According to the different surface quality, it can be divided into galvanized pipe (commonly known as white iron pipe) and non galvanized pipe (commonly known as black iron pipe). Spiral seam welded steel pipe is divided into automatic submerged arc welded steel pipe and high frequency welded steel pipe.
According to its manufacturing method, steel pipe can be divided into seamless steel pipe and welded steel pipe. Seamless steel pipe is made of high quality carbon steel or alloy steel, including hot rolling and cold rolling (drawing). Welded steel pipe is made of rolled steel plate welded by butt joint or spiral joint. In terms of manufacturing method, it is also divided into welded steel pipe for low-pressure fluid transmission, spiral welded steel pipe, direct rolled welded steel pipe, welded pipe, etc. Seamless steel pipe can be used for all kinds of liquid and gas pipes. Welded pipes can be used for water pipes, gas pipes, heating pipes, etc.
Seamless steel pipe is divided into hot rolled pipe and cold drawn (rolled) pipe according to the manufacturing method. The maximum nominal diameter of cold drawn (rolled) pipe is 200mm, and the maximum nominal diameter of hot-rolled pipe is 600mm. In pipeline engineering, when the pipe diameter is more than 57mm, hot-rolled pipe is often used, and when the pipe diameter is less than 57mm, cold drawn (rolled) pipe is often used. There are three kinds of seamless steel pipes commonly used in pipeline engineering:
Spiral seam high-frequency welded steel pipe spiral seam high-frequency welded steel pipe, there is no same product scale, generally using ordinary carbon steel Q235, q235f and other steel products.
Seamless steel pipe is supplied according to outer diameter and wall thickness. There are many kinds of wall thickness under the same outer diameter, and the pressure range is large. Generally, the length of steel pipe is 3-12.5m for hot-rolled pipe and 1.5m-9m for cold drawn (rolled) pipe. The inner and outer walls coated with a zinc protective layer are about 3% - 6% heavier than the non galvanized ones. According to the different wall thickness of the pipe, it can be divided into thin-walled pipe, common pipe and thickened pipe. The thin-walled tube is not suitable for conveying medium and can be used as casing. The straight seam rolled electric welded steel pipe can be divided into the electric welded steel pipe and the straight seam rolled welded steel pipe made of steel plate in blocks on site. It can be made into several pipe wall thicknesses.
Spiral seam automatic submerged arc welded steel pipe can be divided into class a pipe and class B pipe according to the pressure of conveying medium. Class a pipes are generally made of ordinary carbon steel Q235, q235f and ordinary Low Alloy Structural Steel 16Mn by welding. Class B pipes are made of Q235, q235f, Q195 and other steels by welding, which are used as low pressure fluid conveying pipes. Welded steel pipe for low-pressure fluid transmission is made of carbon mild steel, which is the most commonly used small-diameter pipe in pipeline engineering. It can be used to transport water, gas, steam and other media. According to the different surface quality, it can be divided into galvanized pipe (commonly known as white iron pipe) and non galvanized pipe (commonly known as black iron pipe). Spiral seam welded steel pipe is divided into automatic submerged arc welded steel pipe and high frequency welded steel pipe.
According to its manufacturing method, steel pipe can be divided into seamless steel pipe and welded steel pipe. Seamless steel pipe is made of high quality carbon steel or alloy steel, including hot rolling and cold rolling (drawing). Welded steel pipe is made of rolled steel plate welded by butt joint or spiral joint. In terms of manufacturing method, it is also divided into welded steel pipe for low-pressure fluid transmission, spiral welded steel pipe, direct rolled welded steel pipe, welded pipe, etc. Seamless steel pipe can be used for all kinds of liquid and gas pipes. Welded pipes can be used for water pipes, gas pipes, heating pipes, etc.
