Pre-bending and sizing are the main steps in the spiral tube forming process. The primary 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 key function of the sizing is to acquire a more accurate diameter of the tube, as the diameter control is the main quality index of the steel tube. The right match between pre-bending and sizing is needed to obtain PEX-AL-PEX 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 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 of the welding wire is exposed, there is no coating, submerged arc welding is indeed pre-paved welding flux to be welded The submerged arc welding wire extends to the flux, as well as the arc is formed beneath the flux. The development procedure of the submerged arc welding is such that the welding wire is in contact with the workpiece.
After the start button is pressed, the welding wire and also the workpiece are energized, and 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, as well as the welding pool is actually created below the arc. Across the arc, the flux melts to create a cavity. The cavity and also the pool carry on and advance, and the metal behind the pool solidifies to form a continuous weld. This method is conducted under the flux, so that we can’t see it using the naked eye. It may 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, the 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 caliber of the welding seam is high. Additionally, it offers the necessary conditions for that delivery of the spiral welded pipe plant, in order that the production period of the larger spiral steel pipe is guaranteed, therefore it is still popular.
1. Pressure-bearing fluid is primarily utilized for the HDPE Pipe fittings since the tube blank, and is also often spirally formed in temperature. It really is employed for welding with double-sided submerged arc welding and is mainly utilized for spiral seam welded steel pipe devices for pressure fluid transportation. The ability of the steel pipe to resist 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 of the steel pipe is large, the transmission efficiency is additionally high, also it can effectively save an investment of laying pipelines. It really is mainly utilized for pipelines that transport oil and gas.
2. General low-pressure fluid transport is primarily 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 rolled steel strip can be used as the tube blank, which is often formed by spiral molding and is made of double-sided submerged arc welding or high-frequency welded steel pipe. It really is used for the building blocks 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 along with 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 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 variety of strict and scientific inspections and tests, the usage of safe and reliable, PERT-AL-PERT pipe, transmission efficiency is additionally high, and can effectively save the laying pipeline investment. It really is mainly utilized for the laying of pipelines connecting petroleum, gas, etc.