Pre-bending and sizing are the main steps in the spiral tube forming process. The key function of pre-bending is to solve the rebound problem of the tube blank, because the size of the rebound directly affects the intrinsic quality of the steel tube; the main reason for the sizing is to obtain a more accurate diameter of the tube, because the diameter control is the main quality index of the steel tube. The right match between pre-bending and sizing is needed to obtain HDPE pipe.
The following is a quick discussion on the formation process and characteristics of submerged arc welding of galvanized spiral steel pipes with 630*3 ribs. The principle of submerged arc welding: Submerged arc welding is using arc thermal energy welding, and manual welding rod arc welding is different: the submerged arc welding of the welding wire is exposed, there is no coating, submerged arc welding is definitely pre-paved welding flux to be welded The submerged arc welding wire extends into the flux, and also the arc is created under the flux. The development procedure of the submerged arc welding is really that the welding wire is in contact with the workpiece.
Right after the start button is pressed, the welding wire and also the workpiece are energized, as well as the welding wire is returned. Withdrawing, the arc ignites, the welding carriage advances, the welding wire is continuously conveyed downwards, the arc is maintained to shed underneath the flux layer, and the welding pool is actually created underneath the arc. Around the arc, the flux melts to create a cavity. The cavity and the pool continue to advance, and also the metal behind the pool solidifies to form a continuous weld. This process is performed under the flux, therefore we can’t look at it using the human eye alone. It could be seen with X-ray photography.
Because the spiral steel pipe adopts the welding technology of submerged arc automatic welding, besides this sort of high production efficiency; the development auxiliary time is less, time for changing the welding rod is saved; the welding conditions are clean and no spatter, as well as the cleaning time is saved; the quality of the welding seam is high. It also offers the necessary conditions for the delivery of the spiral welded pipe plant, in order that the production duration of the big spiral steel pipe is guaranteed, so it is still widely used.
1. The stress-bearing fluid is primarily employed for the HDPE pipe fittings since the tube blank, and it is often spirally formed in temperature. It really is used for welding with double-sided submerged arc welding and it is mainly employed for spiral seam welded steel pipe devices for pressure fluid transportation. The ability of the steel pipe to withstand pressure is strong as well as the welding performance is also great. After a variety of rigorous scientific inspections and tests, making use situation is comparatively safe and reliable. The solid diameter in the steel pipe is big, the transmission efficiency is additionally high, also it can effectively save the investment of laying pipelines. It is mainly used for pipelines that transport oil and natural gas.
2. General low-pressure fluid transport is mainly hot-rolled steel coiled tube blanks, often temperature spiral molding, using high-frequency lap welding way of general low-pressure fluid conveying spiral seam high-frequency welded steel pipe. Welding steel with spiral welds.
3. The new rolled steel strip is utilized as the tube blank, that is often formed by spiral molding and is made from double-sided submerged arc welding or high-frequency welded steel pipe. It is actually used for the building blocks pile steel pipe for civil building structures, wharves, and bridges.
4. The overall low-pressure fluid transport is hot rolled steel strip coiled tube, regular temperature spiral molding, using double-sided automatic submerged arc welding or single-sided welding method for water, gas, air and steam as well as other general low-pressure fluid transport Submerged arc welded steel pipe.
5. The pressure fluid transport is based on the hot-rolled steel strip for tube blanks, regular temperature spiral molding, high-frequency lap welding method employed for pressure fluid transmission spiral seam high-frequency welding steel pipe device. The steel tube has strong pressure bearing capacity and good plasticity, which facilitates welding and processing. After qfsnvy number of strict and scientific inspections and tests, using safe and reliable, PEX-AL-PEX pipe, transmission efficiency is additionally high, and may effectively save the laying pipeline investment. It is actually mainly utilized for the laying of pipelines connecting petroleum, gas, etc.