Q460b large diameter thick wall coiled pipeDiscussion on Inspection and Maintenance Methods

announcer:hp709HP180518493 release time:2022-02-28 09:05:01

Electric fusion connection: when the pipe fittings leave the factory, the resistance wire is buried in the pipe fittings to make electric fusion pipe fittings. At the construction site, only the plug of the special welding instrument and the socket of the pipe fittings need to be connected. The inner body of the pipe fittings melts the outer plastic of the pipe fittings and the inner plastic of the pipe fittings to form a reliable connection, and combines the timing methods such as special digital timekeeper and installation indicator hole.

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.

.997 technical standard for fusion bonded epoxy powder coating of steel pipeline

This measurement method overcomes the problem of steel

.Generally,Q355b welded steel pipe, the wall thickness of the coiled pipe is 20mm and the outer diameter is 450-3000mm. It is directly welded, 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 rolled pipe shall meet the specified arc degree, end face deviation, straightness, etc.

The butt joint of coiled pipe (with the same wall thickness) shall not exceed 10% of the wall thickness and not more than 2mm.


Q460b large diameter thick wall coiled pipeDiscussion on Inspection and Maintenance Methods



Generally, the wall thickness of coiled pipe is 20mm and the outer diameter is 450-

In order to realize the welding process of high frequency welding of steel plate, the charge induction between welding wire and welding coil is used to heat the weld to the edge of the weld. High frequency welding is a kind of induction welding (or pressure welding). It does not need welding filler and welding. It has narrow welding heat affected zone, beautiful welding shape and good welding mechanical properties. Therefore, it is widely used in steel pipe production. The pressure test of continuous pipe is carried out according to its specification and thickness, and its pressure bearing is also different. This thickness of welded pipe can withstand about 4kg to 10kg. I have been engaged in all kinds of hot-rolled steel pipes, thick wall straight seam coiled pipes, steel casing, coiled pipe factory and other materials all year round. I operate in good faith. Welcome to call! The following are the pressure test results of various pipes: specification working pressure (MPA) hydrostatic test pressure (MPA) ordinary steel pipe 00 thickened steel pipe 60 ductile iron socket straight pipe allowable pressure socket straight pipe dn40-dn250 allowable working pressure (PFA) 5-4mpa 4-4mpa large allowable working pressure (PMA) 0-7mpa 5-7mpa allowable test pressure (pea) 5-6mpa prepared according to standard metallography, Make the cut sample into metallographic sample. After 4% corrosion was removed from the ultrasonic generator, metallographic analysis was carried out on JSM-5610LV scanning electron microscope.

The products are widely used in petroleum, chemical industry, natural gas transportation, pile driving and urban water supply, heating, gas supply and other projects. The wall thickness of the hot-rolled thick wall coil of retailers generally exceeds 20mm, and the outer diameter range is 450-3000mm. The hot-rolled thick wall coil is rolled, welded, formed, de reinforced, flaw detected and delivered under the state of steel plate heating. Sometimes the wall with special thickness needs secondary heating. It is characterized by small outer diameter tolerance and uniform wall thickness. The main thing is that the hot-rolled thick wall quality management coil will not damage the performance of raw materials. The disadvantages of hot-rolled thick wall coil are long processing time and the diameter of thick wall coil is generally above dn450.

packing.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 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, large-diameter thick wall 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, * which will eventually lead to the bias flow of weld metal.

The influence of welding process parameters mainly includes two aspects: according to the production characteristics of spiral steel pipe, the welding current is usually smaller for internal welding and larger for external welding. However, under the condition of large welding current the stirring effect of molten pool is intensified, and the melting amount of welding wire is also the same

, low cost. The rolling pipe is mainly used for pipes, billboards, columns, etc.


Q460b large diameter thick wall coiled pipeDiscussion on Inspection and Maintenance Methods



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, bridge, roller, etc.

Inspection items.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, 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 Q235, Q345, 20, 16 manganese, 16 manganese capacity,20# large diameter thick wall coiled pipe, etc. Product executive standards include: GB / t50205-2001, GB / t3092-2001, etc. The products are widely used in petroleum, chemicals, natural gas transportation, pile driving, urban water supply, heating, gas supply and other projects. When the coiled pipe is greater than 600mm two longitudinal welds are allowed, superheated steam pipes, water wall pipes and superheated steam pipes, large smoke pipes and small smoke pipe carbon structural steel hot-rolled or cold-rolled (drawn) seamless steel pipes for locomotive boilers. No. 20 and 45 steel are mainly used for steel plate rolling. In addition to ensuring chemical composition and mechanical properties, and cold rolling (pulling) shall be delivered in heat treatment state.

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,Q460b welded pipe, 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.

.The latter stage is called unloading regression. At this time, the sector continues to retract from the circumferential position of the rewind pipe before rewinding, and will eventually reach the initial expanding position, which is the small shrinking diameter of the sector required by the expanding process. In practical application, in the process simplification, the three steps can be combined and simplified, which has no impact on the expanding quality of steel pipe. How to calculate the weight per meter of steel coil? Steel coil belongs to steel pipe, so it is combined with general formula when carrying out theoretical weight.

Weld size has a great influence on the quality of rolled steel pipe. Weld size mainly includes welding process parameters, welding wire shape and position parameters, flux flow, then the upper level, and then the difficulty. In principle, the pipes connected to the machine are arranged from inside to outside to reduce the impact of welding stress on the installation accuracy of the machine. The joints of indoor and outdoor pipes shall be left outdoors. Q345B thick wall continuous pipe is a widely used carbon steel material. Q345B thick wall continuous pipe with thickness greater than 10mm is widely used in drainage engineering, sewage pipeline, dredging pipeline construction pipeline, etc. Q345B thick wall continuous pipe is a welded steel pipe product with relatively simple and flexible process. This kind of steel pipe is usually not in stock and is customized. If the quantity is small, the raw materials are not good. The main problem of Q345B thick wall continuous pipe is welding. As long as possible, delivery related requirements can be compared with other products.