Pre-bending and sizing are the main steps within the spiral tube forming process. The main purpose 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 primary reason for the sizing is to have a better diameter of the tube, as the diameter control is the main quality index of the steel tube. An appropriate match between pre-bending and sizing must obtain PEX-AL-PEX pipe.
This is a brief discussion on the formation process and characteristics of submerged arc welding of galvanized spiral steel pipes with 630*3 ribs. The key of submerged arc welding: Submerged arc welding is the use of arc thermal energy welding, and manual welding rod arc welding is different: the submerged arc welding from the welding wire is exposed, there is absolutely no coating, submerged arc welding is actually pre-paved welding flux to get welded The submerged arc welding wire extends to the flux, as well as the arc is actually created underneath the flux. The formation procedure of the submerged arc welding is certainly that the welding wire is in touch with the workpiece.
Right after the start button is pressed, the welding wire as well as 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 lose underneath the flux layer, as well as the welding pool is formed below the arc. Round the arc, the flux melts to form a cavity. The cavity and also the pool carry on and advance, and also the metal behind the pool solidifies to create a continuous weld. This process is carried out beneath the flux, so we can’t see it using the human eye alone. It could be seen with X-ray photography.
Since the spiral steel pipe adopts the welding technology of submerged arc automatic welding, besides this type of high production efficiency; the production auxiliary time is less, time for changing the welding rod is saved; the welding conditions are neat and no spatter, and the cleaning time is saved; the standard of the welding seam is high. It also provides the necessary conditions for that delivery from the spiral welded pipe plant, so the production period of the large spiral steel pipe is guaranteed, so it is still popular.
1. The pressure-bearing fluid is primarily used for the HDPE pipe fittings as the tube blank, and is also often spirally formed in temperature. It is employed for welding with double-sided submerged arc welding and is also mainly utilized for spiral seam welded steel pipe devices for pressure fluid transportation. The capability from the steel pipe to resist pressure is strong and also the welding performance can also be excellent. After a variety of rigorous scientific inspections and tests, the use situation is fairly safe and reliable. The solid diameter of the steel pipe is big, the transmission efficiency is also high, also it can effectively save your time and money of laying pipelines. It really is mainly utilized for pipelines that transport oil and gas.
2. General low-pressure fluid transport is mainly hot-rolled steel coiled tube blanks, often temperature spiral molding, using high-frequency lap welding method for general low-pressure fluid conveying spiral seam high-frequency welded steel pipe. Welding steel with spiral welds.
3. The new rolled steel strip is used as the tube blank, which can be often formed by spiral molding and is made from double-sided submerged arc welding or high-frequency welded steel pipe. It is used for the foundation pile steel pipe for civil building structures, wharves, and bridges.
4. The general 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 way of water, gas, air and steam as well as other general low-pressure fluid transport Submerged arc welded steel pipe.
5. The stress fluid transport is based on the hot-rolled steel strip for tube blanks, regular temperature spiral molding, high-frequency lap welding method used 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 variety of strict and scientific inspections and tests, using safe and reliable, PERT-AL-PERT pipe, transmission efficiency can also be high, and will effectively save the laying pipeline investment. It is mainly employed for the laying of pipelines connecting petroleum, gas, etc.