Q355b large diameter welded pipeThe molding process is different

When the pipe is rolled the distance between the two welds shall be greater than 100mm, and the distance between the outer wall of the outer branch pipe shall not be less than 50mm.

The weld reinforcement is increased, the weld formation is deteriorated and the edge transition is poor.

.It shall be selected according to the design regulations?? Flange connection is an important connection mode in pipeline construction. The flange is divided into threaded (threaded) flange and welded flange. Low pressure small diameter threaded flange, high pressure and low pressure large diameter are welded flanges.

Let me introduce the standard coil produced by steel plate. In the process of rolling,45# thick wall welded pipe, the surface of the circuit board should 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.

.High. Hot rolled thick wall coiled pipe is widely used: oil cylinder, hydraulic pressure, bridge, roller, etc.

Welding voltage because the welding arc is conical, and the welding voltage directly affects the length of the arc. Therefore, the production process of thick wall coiled pipe can be divided into cold drawing and hot rolling. The production process of cold rolled seamless steel pipe is generally more complex than hot rolling. Roll sizing test shall be carried out for the pipe blank first. If the surface does not respond to the crack, the round pipe shall be cut by cutting machine to cut the blank with a length of about meters. However, when entering the annealing process, acid shall be used for annealing, and attention shall be paid to whether a large number of bubbles are generated on the surface. If a large number of bubbles are generated, it indicates that the quality of steel pipe can not meet the response standard. In appearance, the cold-rolled seamless steel pipe is shorter than the hot-rolled seamless steel pipe, and its wall thickness is generally smaller than that of the hot-rolled seamless steel pipe, but the surface is brighter than that of the thick wall seamless steel pipe. There is not too much roughness on the surface, and there are not too many burrs in the diameter. The thick wall coiled pipe is a powerful manufacturer, quotation, honest operation, genuine and of the same quality. The thick wall coiled pipe is available from stock, with complete specifications,. With the increase of welding voltage, the arc length increases, the moving range of arc spots expands, the weld pool widens, and a wider weld formation will be obtained. If welding is carried out in a horizontal position, it will only change the width of the weld without affecting the edge transition of the weld. However, the external welding of spiral welded pipe is carried out on the slope, and the molten weld metal will flow laterally under the action of gravity. We specialize in providing hot-rolled steel pipes, thick wall straight seam coils, steel casings and quality assurance of pipe rolling factory. New and old customers are welcome to consult during the preferential activities. It can be seen that the larger the welding voltage is, the wider the molten pool is,20# large diameter thick wall coiled pipe, * which will eventually lead to the bias flow of weld metal.

In short, the use standard of coiled steel pipe is very important, and the above points can be reasonably explained. For the information of our rolled steel pipe, let's simply say so much today. If you need it, you can directly consult our manufacturer.

Before starting up, wrapping, sealing and other processes, as well as related pre and post processes, such as cleaning, stacking and disassembly. Because it is used strictly, the process of thick wall rolling pipe shall be strict, and the production shall be carried out according to the correct methods and principles. In addition, the process of thick wall rolling pipe also includes stamping on the package. The use of mechanical packaging products can improve productivity, reduce labor intensity and meet the needs of large-scale production. Thick wall coiled pipe is developed with the emergence of new packaging materials and the continuous innovation of packaging technology. It can show important value in different industries and fields.

Quality improvement.The weld reinforcement is increased, the weld formation is deteriorated and the edge transition is poor.

Welding voltage because the welding arc is conical and the welding voltage directly affects the length of the arc. Therefore, the general production process of thick wall continuous pipe can be divided into cold drawing and hot rolling. The production process of cold rolled seamless steel pipe is generally more complex than that of hot rolled steel pipe. First, the pipe must be subject to winding diameter test. If there is no response crack on the surface, the round pipe will be cut and the growth of the blank is about M. However, during annealing, acid should be used for annealing, and attention should be paid to whether there are a large number of bubbles on the surface. If a large number of bubbles appear the quality of the steel pipe will not meet the response standard. The appearance of cold-rolled seamless steel pipe is shorter than that of hot-rolled seamless steel pipe, and the wall thickness is generally smaller than that of hot-rolled seamless steel pipe but the surface is brighter than that of thick wall seamless steel pipe, the diameter is not too prickly, and the strength is high. The manufacturer offers,20# reel, operates in good faith, and has a real price. The same specification, thick wall continuous pipe, spot supply, and complete specifications, the arc length increases, the weld width will be changed, but the edge transition of the weld will not be affected. However, the external welding of spiral welded pipe is carried out on the slope, and the molten weld metal will flow laterally under the action of gravity. We specialize in providing hot-rolled steel pipe, large-diameter thick wall continuous pipe, thick wall straight seam continuous pipe, steel casing and quality assurance of pipe rolling plant. During the preferential activities, new and old customers are welcome to consult. Therefore, the greater the welding voltage the wider the weld pool, the more serious the transverse flow of weld metal, and finally lead to the bias of weld metal.

In general, the process of expanding the diameter of coiled pipe products can be divided into three stages. It is the preliminary rounding stage: the sector blocks are opened until all the sector blocks reach the steel pipe. At this time, the radius of each point in the steel pipe is almost the same within the step range, and the steel pipe is preliminarily rounded. The second stage is the nominal inner diameter stage: the sector starts to reduce the movement speed from the front position until it reaches the required position, which is the inner circumference position of the finished pipe with quality requirements.

The thickness of thick wall coiled pipe is generally greater than 20mm, and the outer diameter range is 450-3000mm. The thick wall coiled pipe is rolled under the condition of steel plate heating Welding, forming, rib defect detection, factory. Sometimes the wall thickness is relatively thick and secondary heating is required. The feature is that the outer diameter tolerance is small Uniform wall thickness.

system.The process of heating the whole thick wall coil or welding area before welding is called preheating. For the steel with high welding strength grade, it has hardening trend, material, especially good thermal conductivity, weldment and large thickness. When the ambient temperature around the welding area is too low, it is necessary to preheat the weldment before welding.

In continuous pipe production, expanding and piercing method is widely used. Large diameter pipe rolling is drilled in the center of the blank φ 20 ~ 40mm guide hole, and then push the stamping rod from the guide hole to expand the guide hole to make the hollow blank extend reversely in the die. The capillary perforation precision is high, and the capillary wall thickness is large, so the perforation precision is high.

The thickness of hot-rolled thick wall coil is generally greater than 20mm, and the outer diameter range is 450-3000mm. The hot-rolled thick wall coil is rolled, welded, formed, ribbed and defect detection under the condition of steel plate heating. Sometimes the wall thickness is relatively thick and secondary heating is required. It is characterized by small outer diameter tolerance and uniform wall thickness. It is important that the hot rolled thick wall coil will not damage the properties of raw materials. The disadvantage of hot roll thick wall rolling pipe is that the treatment time is long. Hot rolled thick wall coiled pipe is widely used: cylinder, hydraulic, bridge, roller, etc.

.Gas and other projects.

The production process of thick wall welded pipe can be divided into cold rolling, cold rolling and hot rolling. The steel pipes are made of 10, 20, 35 and 45, which are referred to as ordinary steel pipes for short, and 16Mn is between ordinary steel pipes and alloy steel pipes. This material is called low alloy steel pipe the steel pipe materials are 27SiMn, 12Cr1MoV, 10crmo9, 15CrMo and 35CrMo, and the stainless steel pipe is collectively referred to as alloy steel pipe. According to the use, it is divided into structural seamless steel pipe; Seamless steel pipe transportation; Seamless steel pipe for boiler; High pressure seamless steel pipe for boiler; High pressure seamless steel pipe for fertilizer equipment; Seamless steel pipe for geological exploration; Jointed steel pipe; Seamless steel pipe for petroleum cracking; Marine seamless steel pipe; Cold drawn cold rolled precision seamless steel pipe; Various alloy pipes.

The diameter of large-diameter thick wall coiled pipe is generally above dn450. 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, old brand, price advantage and quality guarantee! Sometimes there are two welds for large-diameter thick wall coiled pipe. Why does this happen? It is mainly due to the problems of raw materials and equipment processing. The steel plate with the required width of large-diameter 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 large-diameter 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 large-diameter thick wall coiled pipe is mainly ultrasonic flaw detector, and the longitudinal weld on the same barrel section of the 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.