What are the uses of seamless steel pipes?

1. General pipe: Due to the strong bending resistance of steel pipes, in recent years, steel pipes have been used in the roof frames, beams, columns, etc. of buildings such as factories and venues. For example: Beijing stadium buildings, Chengdu, Shanghai, Shenyang and other airport terminal buildings. China's domestic and international standards of production of high-quality carbon structural steel, low-alloy structural steel, alloy structural steel, stainless steel and other grades of seamless steel pipe in the development of the national economy and improve people's living standards play an increasingly important role.

2. High-pressure seamless steel pipes for thermal power generation boilers: Schematic diagram of power station boilers: the process of heating water into steam and superheating steam: when softened water enters the boiler, it first enters the economizer, uses the residual heat of the flame in the furnace to heat the economizer to increase the temperature of the water, then enters the water wall tubes arranged around the furnace, and heats the water wall through the flame burning in the furnace, the water in it is converted into steam with water, which is collected in the drum for water and steam separation. The separated water then enters the water wall. The steam enters the superheater located in the upper part of the furnace and is further heated to make the steam reach the required temperature and pressure. Finally, it is sent to the steam turbine through the steam conduit outside the furnace. The temperature and pressure of the steam that has been worked in the steam turbine have greatly decreased and should be sent back to the boiler, reheated by a reheater to superheated steam for reuse. The technical performance of high-pressure boiler tube is also continuously improved with the development of power plant units. At the beginning of the construction of nearly 10000 kilowatts, 100000 kilowatts, 200000 kilowatts, 300000 kilowatts and 600000 kilowatts were built later. Now the capacity of a single generator set in Pudong's newly built power plant has reached 900000 kilowatts. This requires the temperature and pressure of the steel pipe in the boiler to increase accordingly. For example, the steam pressure has gradually increased from the earliest 4Mpa to the current 25-30Mpa, the steam temperature has also increased from 450 ℃ to 540~560 ℃, and the maximum wall temperature of the superheater and reheater tubes has reached 600-630 ℃. In order to meet the development requirements, the steel of high-pressure boiler tubes has been developed from carbon steel to low-alloy steel, alloy steel, and high-alloy heat-resistant steel containing chromium, molybdenum, vanadium and other alloying elements, and the purity of steel is required to be higher.

3. Oil well pipes for extracting oil and natural gas. Oil and natural gas are buried deep in the ground. When extracting oil and gas, drilling tools must be used to drill wells (oil wells and gas wells) down the ground. Except for drill bits, all drill strings are connected by steel pipes. It is the core drilling tool used to drive drill bits from the ground to the bottom of the well, and it is also a channel from the ground to the bottom of the well. The drill string is composed of Kelly, drill pipe (including a small amount of heavy drill pipe) and drill collars, most of which are drill pipes. During the drilling process, the drilling machine rotates the kelly, the drill pipe is connected to the lower end of the kelly, and the drill collar and the drill bit are connected to the lower end of the drill pipe. Therefore, the drill pipe plays the role of transmitting power and transporting mud. As the borehole deepens, drill rods shall be added one by one and connected to continuously lengthen the drill string to the specified depth. During the drilling process, a casing is inserted to support the well wall of the oil and gas well according to the formation conditions.