Anticorrosive steel pipes are applied to corrosion of underground long-distance pipe transportation. The outer wall adopts the hot melt winding technology. Three epoxy resin coating layers are formed at the bottom. The middle is the adhesive, and the outer side is the PE anti-corrosion coating. The inner wall adopts the hot epoxy powder spray method to resist corrosion. Powder is heated and molten at a high temperature, and then is evenly coated on the surface of the pipe to form a steel-plastic alloy layer.
Through pretreatment of the surface of anticorrosive steel pipes with different methods, all the steel pipes are under pressure. Application of cyclical anticorrosive steel pipes: the basic materials of anticorrosive steel pipes include spiral pipes, straight-joint pipes and seamless pipes. They are widely applied in petroleum, chemical, natural gas and other industries. They are applied in pipeline engineering fields like thermal power, sewage treatment, water source, bridge, steel structure, seawater transportation piles, etc. and applicable to water supply of high-rise buildings, heat supply of the heat supply network and self-support.
The surfacing of 3PE anticorrosive steel pipes is high-density PE anti-corrosion coating. The middle layer is copolymerized adhesive with the branching structure function. The coating is the epoxy powder anti-corrosion coating for contact between the steel pipe surface and the bottom layer. 3PE enhanced anticorrosive steel pipes featured with wide application and the most production are mainly used as pipes or structural parts for conveying fluids. 3PE anticorrosive steel pipes for general purposes are made through rolling of structural alloy steel, ordinary carbon structural steel or low-alloy structural steel.
Spiral steel pipes are suitable for corrosion resistance of a variety of steel structures, water gates, coal gas tanks, wharfs, ships and equipment in oil refining and chemical plants, and for leakage prevention and waterproofing of cesspits, concrete pipes, roof waterproof layers, basements, bathrooms and other concrete structures. Meanwhile, they are mainly used for corrosion resistance of outer walls of buried or underwater steel pipes for transmitting gas, oil, heat and water.
Spiral steel pipes are suitable for corrosion resistance of a variety of steel structures, water gates, coal gas tanks, wharfs, ships and equipment in oil refining and chemical plants, and for leakage prevention and waterproofing of cesspits, concrete pipes, roof waterproof layers, basements, bathrooms and other concrete structures. Meanwhile, they are mainly used for corrosion resistance of outer walls of buried or underwater steel pipes for transmitting gas, oil, heat and water.
Spiral steel pipes are suitable for corrosion resistance of a variety of steel structures, water gates, coal gas tanks, wharfs, ships and equipment in oil refining and chemical plants, and for leakage prevention and waterproofing of cesspits, concrete pipes, roof waterproof layers, basements, bathrooms and other concrete structures. Meanwhile, they are mainly used for corrosion resistance of outer walls of buried or underwater steel pipes for transmitting gas, oil, heat and water.
Spiral steel pipes are suitable for corrosion resistance of a variety of steel structures, water gates, coal gas tanks, wharfs, ships and equipment in oil refining and chemical plants, and for leakage prevention and waterproofing of cesspits, concrete pipes, roof waterproof layers, basements, bathrooms and other concrete structures. Meanwhile, they are mainly used for corrosion resistance of outer walls of buried or underwater steel pipes for transmitting gas, oil, heat and water.
Spiral steel pipes are suitable for corrosion resistance of a variety of steel structures, water gates, coal gas tanks, wharfs, ships and equipment in oil refining and chemical plants, and for leakage prevention and waterproofing of cesspits, concrete pipes, roof waterproof layers, basements, bathrooms and other concrete structures. Meanwhile, they are mainly used for corrosion resistance of outer walls of buried or underwater steel pipes for transmitting gas, oil, heat and water.
Type-I weld joints of Zhongyuan spiral weld pipes: all the weld joints in Y-branch pipes. 2. Longitudinal joints on steel pipe walls. 3. Circumferential welds of steel pipes. 4. Circumferential welds closed through pinching. 5. Weld joints are between the baffle and the pipe wall. If such weld joints are detected with the ultrasonic detection method, the detection rate shall be 50%, the detection rate of x-ray detection shall be 5%, and the required quality shall be B1.
Before spiral steel pipes shall be subject to mechanical performance, flattening and flaring tests and meet the stipulations of standards before leaving the factory. The quality inspection methods for spiral steel pipes are as follows:
1. Surface observation, i.e. appearance inspection. As a simple but widely applied inspection method as well as an important content of inspection for finished products, appearance inspection of weld joints is mainly used for identifying defects and dimensional deviations on the surface of weld joints. Generally speaking, appearance inspection is conducted by naked eyes with the help of standard templates, gauges and magnifying glass. If there are defects on the surface of weld joints, it is estimated that there are defects inside such weld joints.
Spiral Steel Pipe - Hebei Spiral Steel Pipe - Spiral Steel Pipe Factory
Spiral steel pipes are suitable for corrosion resistance of a variety of steel structures, water gates, coal gas tanks, wharfs, ships and equipment in oil refining and chemical plants, and for leakage prevention and waterproofing of cesspits, concrete pipes, roof waterproof layers, basements, bathrooms and other concrete structures. Meanwhile, they are mainly used for corrosion resistance of outer walls of buried or underwater steel pipes for transmitting gas, oil, heat and water.
Bending of spiral weld pipes of spiral steel pipes: plates can be bent for 180°, but to reduce cracks on the curved surface, the radius is two times of the thickness, the thickness radius of thick plates is determined twice in the rolling direction, and the bending direction shall be vertical to the rolling direction. The radius that is 4 times of the plate thickness shall be guaranteed, especially in the case of welding. To prevent processing cracks, the surface of the welding area shall be ground.
The welding repair method of spiral weld pipes with crack is one of the methods for heat resistance of stainless steel. With extraordinary inoxidizability and corrosion resistance performance, it is usually applied to pipes of alkali made through electrolysis with ion-exchange film. However, the material has high requirements for the technology, so serious potential hazards will be caused once the alloying element and the filling material of the base is incomplete, the weld process is unsuitable, the working condition is not good, medium in the pipe is corroded, there are working stress and pipe crack, etc. Therefore, crack recovery is also one good repair method.
Production process of the spiral steel pipes produced by Hebei spiral steel pipe factory (Zhongyuan Pipeline Manufacturing Co., Ltd.):
1. Inspection of raw materials: band steel coil, welding wire, welding machine.
2. Band steel shall be preformed after straightening, shearing, planing and rolling.
3. The weld joint and molding caliber of spiral steel pipes produced by Hebei spiral steel pipe factory (Zhongyuan Pipeline Manufacturing Co., Ltd.) are controlled and adjusted.
4. Automatic steel pipe weld molding with double-sided submerged arc welding machine
Since steel has good physical, chemical and mechanical properties, it can be used for rolling, piercing, drawing, punching, etc. So, spiral weld pipes sold by Zhongyuan Pipeline Manufacturing Co., Ltd. are more widely applied than cast iron. Forging cast iron is used for producing cast iron parts. About 90% cast iron is smelt and made into steel in steelmaking to meet demands of all walks of life.
Processing and welding of spiral weld pipes: iron rust, oil, water and paint that does harm to welding shall be removed before welding. The same grade of steel welding rods shall be selected. Its spot welding time interval is shorter than that of carbon steel, so the spiral weld pipe brush shall be used when cleaning up welding slags. After welding, the surface shall be ground or cleaned up to prevent local corrosion or reduce the strength.