20# large diam
20# large diamThe main purpose of preheating is to reduce the cooling rate of welded joints and preheat temperature. As can be seen from the table, preheating can reduce the cooling rate, but basically does not affect the time spent at high temperature, which is ideal. Therefore, when welding thick wall coils with hardening trend, the main technical measure to reduce the cooling rate and hardening trend is preheating rather than increasing the line energy. Plasma cutting of thick wall coiled pipe is more effective than gas cutting
The main purpose of preheating is to reduce the cooling rate of welded joints and preheat temperature. As can be seen from the table, preheating can reduce the cooling rate, but basically does not affect the time spent at high temperature, which is ideal. Therefore, when welding thick wall coils with hardening trend, the main technical measure to reduce the cooling rate and hardening trend is preheating rather than increasing the line energy. Plasma cutting of thick wall coiled pipe is more effective than gas cutting
.Clean up the workplace and eliminate unsafe factors.
The steel plate rolling pipe we call the steel plate rolling pipe is actually a process. The following small series will describe the process sequence: plate inspection, blanking beveling, steel plate rolling, assembly spot welding, campus, perimeter and roundness deviation inspection, weld inspection, large-diameter thick wall rolling pipe, thick wall straight seam rolling pipe, rolling pipe factory and other special products, old brands, price advantages and guaranteed quality. These processes can not be less.
.However, the disadvantages of manual cutting and cutting are also obvious, and the quality of the incision is very poor Big size error There is a great waste of materials The post-treatment process has large processing capacity and poor working conditions. Cutting with a forming machine can greatly improve the quality of the workpiece, but the workpiece must be pre machined. It is not suitable for blanking of single chip small batch and large workpiece. Although the semi-automatic cutting machine reduces the labor intensity, its function is simple and is only suitable for cutting two shapes. Due to the low cost of equipment, so even in some large enterprises, it is still widely used in small and medium-sized enterprises.
The wall thickness of hot coil thick wall continuous pipe is generally greater than 20mm, and the outer diameter range is 450-3000mm. Hot rolled thick wall continuous pipe is rolled, welded formed, reinforced, flaw detected and delivered under the condition of steel plate heating. Sometimes the wall thickness is very special and needs secondary heating. It is characterized by small outer diameter tolerance and uniform wall thickness. The main reason is that the hot rolled thick wall continuous pipe will not damage the performance of raw materials. The disadvantages of hot rolled thick wall continuous pipe are long processing time and high cost. Hot rolled thick wall pipe is widely used: oil cylinder, hydraulic, bridge, roll, etc. Compared with seamless steel pipe, thick wall continuous pipe has the disadvantages of low cost, fast delivery, breaking the fixed specification of seamless steel pipe and so on. Thick wall coil is welded by bending steel plate or steel strip. According to the weld form, it is divided into straight welded pipe and spiral welded pipe. It can be divided into ordinary welded pipe, galvanized welded pipe, oxygen blowing welded pipe, wire sleeve, metric welded pipe, idler pipe, deep well pump pipe, automobile pipe transformer pipe, welded thin-wall pipe, welded special-shaped pipe and spiral welded pipe. It is a special product manufacturing enterprise integrating research, development and service. It has long been specialized in hot-rolled steel pipe, large-diameter thick wall rolling pipe, thick wall straight seam rolling pipe, steel casing and rolling pipe factory. Continuous pipe is committed to producing all kinds of circumferential seam and longitudinal circumferential continuous pipe and penstock, and is reformed on the basis of the same specification and model of traditional rolling equipment. The function of parameters of coil welded steel pipe equipment is improved by 30%, which fills the gap that can not be produced by traditional rolling equipment. It can produce steel pipes with diameter of more than 400 and wall thickness of 8-100mm. The main materials are q23 q34 20, 16Mn, 16Mn, etc. the product standards are GB / t50205-200, GB / t3092-2001, etc. the products are widely used in petroleum, chemical industry, natural gas transmission, pile driving, urban water supply, heating, gas supply and other projects.
The diameter of thick wall coiled pipe is usually higher than dn450. Thick wall coiled pipe is sometimes two welds. The reason why this happens is mainly due to the problems of raw materials and equipment processing. The steel plate with the required width of welded pipe required by the customer is usually not produced by the steel plant, so two plates need to be welded, so the weld will occur.
1800mm steel pipe elbow detailed introduction to elbow: first of all, the material is hot pushed, the pusher is a horn shaped core or mandrel, the mandrel is thickened and thickened, the process of pushing the elbow is the process of expanding the diameter, and it is supported on the back. The material tube part passes through the mandrel, and there is an arched frame at the rear to fix the mandrel. There's a car in the middle. Some cars are driven hydraulically, others are driven by mechanical transmission, that is, and then the car pushes forward, and the car pushes the pipeline along the core. The rod moves forward there is an induction coil outside the mandrel, the tube is heated and heated, and then the trolley pushes the tube down and processes one.
Area calculation: outer wall area = 14 * D (outer diameter) * length, e.g. 100m 820 * 10 carbon steel coil, area = 14 * (outer diameter thickness) * length, e.g. 100m 820 * 10 carbon steel coil, area = 14 * (0.82-0.01 * * 100 = 25 2M2. It is known that the cost is calculated by multiplying the area by the unit price.
In the production process, the hot-rolled steel pipe has the characteristics of no raw materials, that is, the mechanical properties of thick wall steel plate. In this way, the steel plate is heated first and then rolled, which softens the steel plate under great conditions, which will not affect the material quality nor damage the properties such as strength, yield and tensile strength. For the wall thickness that can not be achieved by cold rolled steel pipe, the specification and model of thick wall steel pipe are added.
Good reputation.Diameter of rolled steel pipe: sometimes the diameter of the demand plan is different from that of the supplier.
When the nominal diameter is greater than or equal to 600mm, back welding shall be carried out in the pipe.
The wall thickness of general coiled pipe is 20mm and the outer diameter is 450-3000mm. It is made of steel plate by direct rolling, welding and forming. The production process of general thick walled 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 pipe blank first. If there is no response crack on the surface, the round pipe shall be cut by cutting machine, Cut into blanks about meters in length. 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,. Docking and strengthening. Coil pipe processing time is short and delivery is fast Low cost. The rolling pipe is mainly used for pipes, billboards, columns, etc.
Have we learned about the packaging process of the steel used? Today, let's discuss the packaging process of lower thick wall coil.
Inspection basis.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, but the surface is brighter than that of the thick wall seamless steel pipe. There is not too much roughness on the surface and its wall thickness is generally smaller than that of the hot-rolled seamless steel pipe, 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, the more serious the trend of lateral flow of weld metal will be, q215-a. & middot; F,Q215-B,Q215-B· F,Q235-A,Q235-B,Q235-B· F. Q235-c ordinary carbon steel: B2 BY2 B2F by2f B3 by3 B3F by3f a2ay2 a2f ay2f A3 ay3 A3F ay3f2 high quality carbon steel: 10 15 20 transmission shaft steel 3 low alloy structural steel: 123mn 16Mn 19mn 08ti 10ti15ti4 special purpose steel thick wall coil is made of steel plate. Long term coil, Q235B coil, Q345B coil, large diameter thin wall coil, large diameter thick wall coil, stainless steel coil,Q235B large diameter reel,Q235B large diameter thick wall coiled pipe, L360 coil, 16Mn coil, 20 old brands, with price advantages and quality! Thick wall coil can be divided into two types: hot coil and thick wall coil.
.It is important that the thick wall coiled pipe will not damage the performance of raw materials. The disadvantage of hot roll thick wall rolling pipe is that the treatment time is long Very expensive. Thick wall rolling pipe is widely used: cylinder, hydraulic, roller, etc.
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, automobile pipe, transformer pipe, electric welding thin-wall pipe, electric welding special-shaped pipe and spiral welded pipe, coil, Q235B coil,16Mn thick wall welded pipe, 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
Weld inspection is necessary to detect the weld quality of steel coil pipe. After welding, all the welds are tested by on-line continuous ultrasonic automatic flaw detector to ensure the NDT coverage of the welds. If there are defects, it will automatically alarm and spray marks, and the production will adjust the process parameters at any time to eliminate the defects in time.