The steel plate or strip is bent and then welded to form a thick wall coil. According to the welding form, it is divided into straight seam welded pipe and spiral welded pipe. According to the purpose, it is divided into ordinary welded pipe, galvanized welded pipe, oxygen blowing welded pipe, wire sleeve, metric welded pipe, rolling pipe, deep well pump pipe, automobile pipe, transformer pipe, welded thin-wall pipe, welded pipe and spiral welded pipe. Coil pipe is dedicated to the production of, longitudinal ring coil pipe and steel pressure pipe, Q345, 20, 16 manganese, 16 manganese capacity, etc. Product executive standards include: GB / t50205-2001, GB / t3092-2001, etc. The products are widely used in petroleum chemicals, natural gas transportation, urban water supply, heating, gas supply and other projects. When the coiled pipe is greater than 600mm, two longitudinal welds are allowed, and the spacing shall be greater than 200mm.
The main problem of thick wall coiled pipe is welding. As long as flaw detection can be carried out, the requirements related to delivery are wider than other products. The detection of thick wall coiled pipe is mainly ultrasonic flaw detector.
.The butt joint of strip steel head and tail adopts single wire or double wire submerged arc welding, and automatic submerged arc welding is adopted for repair welding after rolled into steel plate and pipe.
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, roller, etc.
.The convex hull on the surface of the crimp roll shall be treated. Before repeated processing, the equipment surface shall be treated to prevent the convex hull steel plate with abnormal roll surface from causing pits.
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.
High. Hot rolled thick wall coiled pipe is widely used: oil cylinder, hydraulic pressure, bridge, roller, etc.
The pipeline installation sequence is based on the principle of sub area and sub system, with small diameter, from the lower layer to the upper layer, from difficult to easy, from the pipe gallery to the equipment. In principle, the pipeline connected with the machine is configured from the inside to the outside to reduce the impact of welding stress on the installation accuracy of the machine. The interface between indoor and outdoor pipelines shall be left outdoors. Q345B thick wall coiled pipe is a kind of material in carbon steel and is widely used. The thickness of Q345B thick wall coiled pipe is generally more than 10mm, which is widely used in drainage engineering, sewage pipeline, dredging pipeline, construction pipeline, etc. Q345B thick wall coiled pipe is a welded pipe product, and the process in the welded pipe is relatively simple and flexible. This type of steel pipe usually has no inventory and is processed by user. If the quantity is small, the raw materials are not good. The main problem of Q345B thick wall coiled pipe is welding. As long as it is possible, the delivery related requirements can be compared with other products.
During the polishing process, a thick layer of iron, nickel and other impurities will be deposited on the surface of the cathode lead plate, which will affect the conductivity of the cathode surface of the steel coil tube resulting in the decrease of current, the negative removal of the polished surface, and seriously affect the polishing quality. Therefore, the deposits on the cathode plate shall be removed in time. Sometimes a hard thick film is formed, which can only be removed by knocking, and then washed clean, so as to ensure why there are two longitudinal welds in the same pipe section?
With the development of domestic economic situation and the acceleration of welding and casting trend, the advantages of NC cutting are gradually recognized. It has long provided various brand products such as hot-rolled steel pipe, large-diameter thick wall rolling pipe, thick wall straight seam rolling pipe, steel casing and rolling pipe factory. The designated products are complete and the quality is guaranteed. NC cutting not only greatly improves the rate of plate and product quality, the NC cutting machines used in the thick wall coil processing industry are mainly flame and ordinary plasma cutting machines but pure flame cutting can not meet the needs of modern production. At present, most NC cutting machines are NC 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, which is mainly reflected in: 90% of the developed thick wall coiled pipe processing industry is digital control cutting machine, and only 10% is manual cutting; The CNC cutting machine only accounts for part of the total blanking. 10% of which the proportion of NC plasma cutting is small. In industrial production, the thermal cutting of thick wall coiled pipe generally includes gas cutting, plasma cutting, laser cutting and so on. Among them, plasma cutting has a wider cutting range than gas cutting More efficient. Fine plasma cutting technology is close to laser cutting in material cutting surface quality, but the cost is much lower than laser cutting. Therefore, since the successful development of the United States in the mid-1950s plasma cutting has developed rapidly. With the rapid development of computer and digital technology, NC cutting is also developing, which improves the machining accuracy. It shows great advantages in saving materials and improving labor productivity. This leads to the development of plasma cutting technology from manual or semi-automatic to NC, which has become one of the main directions of NC cutting technology. NC plasma cutting technology is a set of high-tech technologies such as NC technology, plasma cutting technology and inverter power supply technology. Its development is based on the common progress of computer, plasma arc characteristic research, power electronics and other disciplines. The CNC cutting technology began in the 1980s, and the CNC plasma cutting technology was later. However, recently, some domestic universities, research institutes and manufacturers have studied NC plasma cutting technology and gradually developed and produced various specifications of NC plasma cutting equipment, narrowing the gap of foreign advanced technology.
Interpretation and observation.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, 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.
Weight per meter of steel plate coil = (outer diameter wall thickness) * wall thickness * 0.0246615 steel plate coil is made of steel plate. Thick wall t-welded coil can be divided into coil and hot rolled thick wall coil.
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.
Cold rolled thick wall continuous pipe is similar to cold rolled thick wall continuous pipe, welded, formed, butted and reinforced. Cold rolled thick wall pipe has the characteristics of short processing time, fast delivery and low cost. Cold rolled thick wall pipe is mainly used for: pipe, billboard, column, etc.
ranking.The steel plate or strip is bent and then welded to form a thick wall coil. According to the welding form, it is divided into straight seam welded pipe and spiral welded pipe. It is divided into ordinary welded pipe, galvanized welded pipe, oxygen blowing welded pipe, wire sleeve, metric welded pipe rolling pipe, deep well pump pipe,45# thick wall welded pipe, automobile pipe, transformer pipe, welded thin-wall pipe, welded pipe and spiral welded pipe. Coil pipe is dedicated to the production of, longitudinal ring coil pipe and steel pressure pipe, and is modified according to similar specifications of traditional rolling equipment. The function of increasing the parameters of spiral steel pipe equipment by 30% fills the gap that the original traditional rolling equipment can not produce. It can produce steel pipes with a diameter of 400 or more and a wall thickness of 8-100mm. The material mainly includes q23 q34 20#, 16 manganese, 16 manganese capacity,Q345B large diameter reel, etc. Product executive standards include: GB / t50205-2001, GB / t3092-2001, etc. The products are widely used in petroleum, pile driving natural gas transportation, urban water supply heating, superheated steam pipes gas supply and other projects.
Basic purpose of steel plate rolling: it is used for all kinds of low and medium pressure boilers, boiling water pipes, water wall pipes and superheated steam pipes, and cold rolling (pulling) shall be delivered in heat treatment state.
Main technical measures for low hardening trend
.Generally, the wall thickness of the coiled pipe is 20mm and the outer diameter is 450-3000mm. It is directly welded,45# welded pipe, formed, rolled, butted, removed and reinforced from the steel plate. The coil pipe has the advantages of short processing time, fast delivery and low cost. The rolling pipe is mainly used for pipes, billboards, etc.
The main materials are q23q3420, 435cimo and 42cimo, 16 manganese and 16 manganese capacity. Generally, cold rolled sheet can be used for pipe rolling, and the product standards are GB / t50205-200, GB / t3092-2001, etc. Continuous pipe is widely used in petroleum, chemical industry, natural gas transmission, pile driving, urban water supply, heat supply, gas supply and other projects.
In order to make you better understand the installation method of coiled pipe, the following coiled pipe factory will introduce the installation method of coiled pipe: pipe hoop is used, and raw silk belt, white hemp wire, pipe expander, handle and other tools are used to connect coiled pipe and pipe fittings. This method may need repeated debugging due to the great influence of human factors. In addition, when the materials of coiled pipes and pipe fittings are different, due to their different thermal coefficients, leakage may occur when cold and hot water are used alternately.?