Year1
- 产品规格：
- 齐全
Characteristics
According to incomplete statistics, my country's existing seamless steel pipe manufacturers have about a number of seamless steel pipe units, with an annual production capacity of more than 10,000 tons. Judging from the caliber, it accounts for % - and it accounts for %. In terms of varieties, general-purpose pipes accounted for 10,000 tons, accounting for 10,000 tons, petroleum pipes accounted for 10,000 tons, .% hydraulic props, precision pipes accounted for 10,000 tons, stainless steel pipes, bearing pipes, and automobile pipes accounted for 10,000 tons in total.
The raw material for rolling seamless pipes is round tube billet. The round tube billet must be cut by a cutting machine into a billet with a length of about one meter and sent to the furnace for heating via a conveyor belt. The billet is fed into the furnace and heated to a temperature of approximately degrees Celsius. The fuel is hydrogen or acetylene. Temperature control in the furnace is a key issue. After the round tube comes out of the furnace, it must be pierced through a pressure punching machine. Generally, the more common piercing machine is the tapered roller piercing machine. This kind of piercing machine has high production efficiency, good product quality, large perforation diameter expansion, and can penetrate a variety of steel types. After perforation, the round tube blank is successively cross-rolled, continuous rolled or extruded by three rollers. After extrusion, the pipe should be removed and calibrated. The sizing machine rotates a tapered drill bit at high speed into the steel blank to drill holes to form a steel pipe. The inner diameter of the steel pipe is determined by the outer diameter length of the drill bit of the sizing machine. After the steel pipe is sized, it enters the cooling tower and is cooled by spraying water. After cooling, the steel pipe will be straightened. After straightening, the steel pipe is sent to the metal flaw detector (or hydraulic test) by the conveyor belt for internal flaw detection. If there are cracks, bubbles and other problems inside the steel pipe, they will be detected. After quality inspection, steel pipes must undergo strict manual selection. After the quality inspection of the steel pipe, spray the serial number, specification, production batch number, etc. with paint. And it is hoisted into the warehouse by a crane.
Classification
Seamless steel pipes are divided into two categories: hot-rolled and cold-rolled (rolled) seamless steel pipes.
Hot-rolled seamless steel pipes are divided into general low-pressure steel pipes, medium-pressure boiler steel pipes, high-pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, geological steel pipes and other steel pipes.
Classification
In addition to general steel pipes, low and medium pressure boiler steel pipes, high pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes and other steel pipes, cold rolled (rolled) seamless steel pipes also include carbon thin Wall steel pipe, alloy thin-walled steel pipe, stainless thin-walled steel pipe, special-shaped steel pipe. The outer diameter of hot-rolled seamless steel pipes is generally greater than the wall thickness. - The outer diameter of cold-rolled seamless steel pipes can be up to the wall thickness. The outer diameter of thin-walled pipes can be less than the wall thickness. Cold rolling has higher dimensional accuracy than hot rolling.
Generally used seamless steel pipes: are made of hot-rolled or cold-rolled high-quality carbon structural steels such as, ,,,, and low-alloy structural steels, or alloy steels such as, Seamless pipes made of low carbon steel such as , , etc. are mainly used for fluid transportation pipelines. Seamless tubes made of medium carbon steel such as , , etc. are used to manufacture mechanical parts such as stressed parts of automobiles and tractors. Generally, seamless steel pipes must ensure strength and flattening tests. Hot-rolled steel pipes are delivered in a hot-rolled or heat-treated state, while cold-rolled steel pipes are delivered in a heat-treated state.
Seamless steel pipes for low and medium pressure boilers: used to manufacture various low and medium pressure boilers, superheated steam pipes, boiling water pipes, water wall pipes and superheated steam pipes, large smoke pipes, small smoke pipes and arches for locomotive boilers. Brick pipes etc. Hot-rolled or cold-rolled (dialed) seamless steel pipes are made of high-quality carbon structural steel. Mainly made of high-grade steel, in addition to ensuring the chemical composition and mechanical properties, hydraulic tests such as crimping, flaring, and flattening are also required. Hot-rolled products are delivered in a hot-rolled state, and cold-rolled (rolled) products are delivered in a heat-treated state.
High-pressure boiler steel pipes: High-quality carbon structural steel, alloy structural steel and stainless heat-resistant steel seamless steel pipes are mainly used to manufacture steam boiler pipes of high pressure and above. These boiler pipes are often exposed to high temperatures and Working under high pressure, the pipe will also undergo oxidation and corrosion under the action of high-temperature flue gas and water vapor. Therefore, the steel pipe is required to have high lasting strength, high anti-oxidation performance and good organizational stability. The steel grades used are: high-quality carbon Structural steel grades include, alloy structural steel grades, , , , , , , , , etc. Rusty and heat-resistant steels are commonly used. In addition to ensuring the chemical composition and mechanical properties, hydraulic pressure tests must be done one by one for high-pressure boiler pipes, and expansion and pressure must be carried out. Flat test. Steel pipes are delivered in heat treated condition. In addition, there are also certain requirements for the microstructure, grain size, and decarburization layer of the finished steel pipe.
Seamless steel pipes for geological drilling and oil drilling: drilling rigs are used to drill wells to explore underground rock formation structures, groundwater, oil, natural gas and mineral resources. The exploitation of oil and natural gas is inseparable from well drilling. Seamless steel pipes for oil drilling are the main equipment for drilling. They mainly include outer core pipes, inner core pipes, casings, drill pipes, etc. Because the drilling pipes have to go deep into the stratum of several thousand meters and the working conditions are extremely complex, the drill pipes are subjected to stresses such as tension, pressure, bending, torsion and uneven impact loads, and are also subject to mud and rock wear. Therefore, the pipes must have sufficient strength. , hardness, wear resistance and impact toughness. The steel used for steel pipes uses d (the prefix of the Chinese pinyin for geology) plus the number one to represent the steel yield point. Commonly used steel grades include D, D, D, D, D. Steel pipes are delivered in heat-treated condition.
Petroleum cracking tubes: seamless tubes for furnace tubes, heat exchanger tubes and pipelines in petroleum refineries. Commonly used are high-quality carbon steel (,), alloy steel (,), heat-resistant steel (,), stainless steel (,). In addition to verifying the chemical composition and various mechanical properties of steel pipes, steel pipes must also ensure water pressure, flattening, flaring and other tests as well as surface quality and non-destructive inspections. Steel pipes are delivered in heat treated condition. Stainless steel pipe: Hot-rolled and cold-rolled stainless steel pipes of various stainless steels are widely used in petroleum and chemical equipment pipelines and stainless steel structural parts for various purposes. In addition to ensuring the chemical composition and mechanical properties, any steel pipe used to withstand fluid pressure must ensure water pressure. The test passed. Various special steel pipes must be guaranteed according to regulations.
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