Thick wall coiled pipe sometimes has two welds. Why does this happen? It is mainly due to raw material problems and equipment processing problems. The width of the welded pipe required by the customer is not produced by the steel plant, so the two plates must be welded, so this kind of weld occurs. The main problem of thick wall coiled pipe is welding. As long as the flaw detection can be carried out, the delivery can be carried out. The relevant requirements are broader than other products. The detection of thick wall coiled pipe is mainly ultrasonic flaw detector, and the longitudinal weld on the same cylinder section of coiled pipe should not be more than two. The group of butt welds of coiled pipe shall be flush. When the nominal diameter is greater than, back sealing welding shall be carried out in the pipe. During pipe rolling processing, the surface damage of the plate shall be prevented. High cost. Hot rolled thick wall coiled pipe is widely used: oil cylinder hydraulic pressure, bridge, roller, etc& amp; amp; quot; Compared with seamless steel pipe, thick wall coil has the disadvantages of low cost, rapid delivery, breaking the fixed specification of seamless steel pipe etc. Quality department 3 editing of welding process and welded pipe type thick wall coiled pipe is made of steel plate or steel strip after bending and then welding. According to the weld form, it is divided into straight welded pipe and spiral welded pipe. According to the purpose, it is divided into general welded pipe, galvanized welded pipe, oxygen blowing welded pipe, wire sleeve, metric welded pipe, idler pipe, deep well pump pipe, automobile pipe, transformer pipe, electric welding thin-wall pipe, electric welding special-shaped pipe and spiral welded pipe. Objective knowledge packaging strategy thick wall steel plate coil - thick wall steel plate coil price thick wall coil is formed by bending steel plate or steel strip, with the electrical model of 031 inspection 8517611 standard, and then made by high-frequency welding and submerged arc welding. According to the weld form, it is divided into straight welded pipe and spiral welded pipe. According to the purpose, it is divided into general welded pipe galvanized welded pipe, oxygen blowing welded pipe wire sleeve, metric welded pipe, idler pipe, deep well pump pipe, automobile pipe, transformer pipe, electric welding thin-wall pipe, electric welding special-shaped pipe and spiral welded pipe, coil, Q235B coil, Q345B coil, large-diameter thin-wall coil, large-diameter thick wall coil, stainless steel coil, L360 coil and 16Mn coil. The inspection is strict and the quality is preferential
What is the manganese content of straight seam coiled pipe? The material of straight seam coiled pipe and an appropriate amount of manganese 1 can significantly improve the cold brittleness of straight seam steel pipe steel, increase the yield strength and tensile strength, reduce the plasticity and impact toughness, and do not be too large; 4 manganese has an effect on the removal of harmful element oxygen in steel; 5MN can also be used to synthesize high melting point (about 1600 ℃, much higher than the general processing temperature of steel), which is at high temperature in steel, so it can reduce the harmful effect of sulfur and lead to hot processing of steel. Sulfur cracked & ldquo; Hot crisp & rdquo; The phenomenon has decreased.
.Surface derusting standard: sand blasting derusting on the outer surface of steel pipe shall reach grade SA2 1 / 2 according to the requirements of GB / T 23-2008, and the depth of anchor grain on the surface of steel pipe shall be 40-100μ M steel plate rolling circle specification range steel plate rolling circle specification range: for steel pipes with an outer diameter of more than 325mm and a wall thickness of more than 20mm, at present, the large diameter of single weld can reach 1220mm, the wall thickness can reach 80 and the diameter can reach 2020mm.
Finish machining is performed below, and after shot peening, the scales on the inner and outer surfaces of the elbow are removed, and both ends are processed with grooves to facilitate welding.
.Gas and other projects.
The function of parameters of pipe rolling equipment is improved by 30% which fills the gap that can not be produced by traditional steel rolling equipment. It can produce steel pipes with diameter of more than 400 and wall thickness of 4-100mm. The main materials are q23q3420, 435cimo and 42cimo, 16 manganese and 16 manganese capacity. Generally speaking, GB / t3092-2001, etc.
Due to the continuous application of thick wall coiled pipe in industry and the continuous expansion of its scope, it has many advantages. In order to prevent the thick wall coiled pipe from rusting, we can apply antirust oil on the surface of the thick wall coiled pipe.
Diameter of rolled steel pipe: sometimes the diameter of the demand plan is different from that of the supplier.
For pipe fittings with nominal pressure indicating their grade or specified pressure and temperature rating, the pressure and temperature rating specified in the standard shall be used as the reference. For example, for pipe fittings with nominal thickness of straight pipe connected to them, the applicable pressure and temperature rating shall be determined according to the reference pipe grade specified in the standard, For example, for pipe fittings with only overall dimensions specified in gb14383 ~ GB standards, confirmatory test shall be conducted to determine their bearing strength.
The butt joint of coiled pipe (with the same wall thickness) shall not exceed 10% of the wall thickness and not more than 2mm.
resources.The rolling pipe factory mainly produces steel plate rolling pipe and thick wall rolling pipe. With the development of domestic economic situation and the acceleration of welding and casting trend, the advantage of NC cutting is gradually recognized. NC cutting not only greatly improves the rate of plate and product quality, but also improves the working environment and labor efficiency. At present, the CNC cutting machines used in the thick wall rolling pipe processing industry are mainly flame and ordinary plasma cutting machines, but pure flame cutting can not meet the needs of modern production, most CNC cutting machines are CNC plasma cutting machines. This type of cutting machine can meet the needs of thick wall coiled pipe plate processing and thick wall coiled pipe parts processing, so the demand will be greater and greater, but there is still a very obvious gap with foreign countries, mainly in
Hot melt installation: pipes are connected according to the nature of thermoplastic coiled pipes. During hot melt, safe and durable, and avoids water running, emitting, dripping and leakage at the joint of metal pipe fittings.
The function of parameters of pipe rolling equipment is improved by 30%, which fills the gap that can not be produced by traditional steel rolling equipment. It can produce steel pipes with diameter of more than 400 and wall thickness of 4-100mm. The main materials are q23q3420, 435cimo and 42cimo, 16 manganese and 16 manganese capacity. Generally speaking, cold-rolled sheet can be used for pipe rolling. Product standards: GB / t50205-200, GB / t3092-2001, etc.
Circumferential deviation of coiled pipe, pipe groove processing and joint pair: when the pipe wall thickness is less than 6mm, it is type I weld; when the pipe wall thickness is greater than 6mm, it is type V weld; For pipes with diameter greater than 600mm and wall thickness greater than 6mm, the bottom of the pipe shall be sealed at the bottom of the pipe; In addition to the lap joint, the other type of gas coil pipe is continuous and solid V-groove butt welding. If the weld is found to be defective, the weld must be re welded. Rewelding shall not be more than twice. Long term supply of hot rolled steel pipe, large diameter thick wall rolling pipe, thick wall straight seam rolling pipe, steel casing, rolling pipe factory has complete products and excellent quality, The price is favorable. The longitudinal weld of the winding pipe with the same cylindrical part shall not be greater than the spacing between two longitudinal joints shall not be less than 200mm. The arc length of the winding pipe calibration template shall be 1 / 6 ~ I of the circumference of the pipe / the gap between the template and the pipe. Let me introduce the steel plate production standard winding pipe. During the winding process, the surface of the circuit board shall be protected from damage. Parts with severe scars shall be ground to achieve transition and the wall thickness of the ground part shall not be less than the design wall thickness.
Quality assurance.The inner diameter of 1800mm steel plate coiled pipe elbow is 1800mm, the bending radius is also 1800mm, four bends, the material thickness is 4mm, and the bending is 90 & deg;.
All the welded welds are subject to on-line continuous ultrasonic automatic flaw detector to ensure the NDT coverage of spiral welds. If defective
Material used for steel plate coil: it is required to be explained by the user.
.If the particle size of straight seam coiled pipe is too small, the adhesion and impact strength of the coating will be reduced. For serious internal pitting corrosion, it can not only rely on the high-strength impact of large particles of rinse agent, but also remove corrosion products with small particles. Reasonable ratio design can not only slow down the speed of pipeline and nozzle (propeller) rinse agent. Wear and tear, and the rate of rinsing agent can be greatly improved. Generally, the particle size of metal particles is 2 - 9mm, and the particle size of metal sand is 1 - 2mm, of which 3 - 5mm is a common component. The sand shot ratio is usually 4 to 9.
Be able to show important value in different industries and fields. When the coiled pipe is greater than 600mm, two longitudinal welds are allowed, and the spacing shall be greater than 200mm.
Because the coiled steel pipe plays an important role in construction, railway construction and bridge construction, it is easy to have an impact. Generally