Pre-bending and sizing are the main steps within the spiral tube forming process. The key 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 reason for 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. An appropriate match between pre-bending and sizing must obtain HDPE pipe.
The following is a short 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 using arc thermal energy welding, and manual welding rod arc welding is unique: the submerged arc welding from the welding wire is exposed, there is not any coating, submerged arc welding is indeed pre-paved welding flux to be welded The submerged arc welding wire extends into the flux, and also the arc is actually created underneath the flux. The formation procedure for the submerged arc welding is really 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 also 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 beneath the flux layer, and the welding pool is created below the arc. Round the arc, the flux melts to form a cavity. The cavity and the pool carry on and advance, and the metal behind the pool solidifies to form a continuous weld. This procedure is conducted beneath the flux, therefore we can’t look at it with all the human eye alone. It may be seen with X-ray photography.
Considering that the spiral steel pipe adopts the welding technology of submerged arc automatic welding, besides this type of high production efficiency; the development auxiliary time is less, the 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. Additionally, it offers the necessary conditions for that delivery from the spiral welded pipe plant, so that the production duration of the big spiral steel pipe is guaranteed, so it is still commonly used.
1. The stress-bearing fluid is principally employed for the HDPE pipe fittings since the tube blank, and is also often spirally formed in temperature. It is used for welding with double-sided submerged arc welding and is mainly employed for spiral seam welded steel pipe devices for pressure fluid transportation. The ability from the steel pipe to withstand pressure is strong and also the welding performance is also excellent. After a number of rigorous scientific inspections and tests, making use situation is comparatively safe and reliable. The solid diameter from the steel pipe is big, the transmission efficiency is additionally high, and it can effectively save the investment of laying pipelines. It is mainly used 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 way of general low-pressure fluid conveying spiral seam high-frequency welded steel pipe. Welding steel with spiral welds.
3. The hot rolled steel strip is utilized because the tube blank, which can be often formed by spiral molding and consists of double-sided submerged arc welding or high-frequency welded steel pipe. It is utilized for the cornerstone 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 technique for water, gas, air and steam and other general low-pressure fluid transport Submerged arc welded steel pipe.
5. The pressure fluid transport relies on the hot-rolled steel strip for tube blanks, regular temperature spiral molding, high-frequency lap welding method utilized 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, the usage of safe and reliable, PEX-AL-PEX pipe, transmission efficiency can also be high, and can effectively save the laying pipeline investment. It is actually mainly used for the laying of pipelines connecting petroleum, natural gas, etc.