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 function of the sizing is to acquire a more accurate diameter of the tube, because the diameter control is the main quality index of the steel tube. An appropriate match between pre-bending and sizing is required to obtain HDPE pipe fittings.
This is a short 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 not any coating, submerged arc welding is definitely pre-paved welding flux to become welded The submerged arc welding wire extends to the flux, and the arc is actually created underneath the flux. The formation process of the submerged arc welding is really that this welding wire is in contact with the workpiece.
Right after the start button is pressed, the welding wire and 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 lose beneath the flux layer, as well as the welding pool is created beneath the arc. Across the arc, the flux melts to form a cavity. The cavity and also the pool still advance, as well as the metal behind the pool solidifies to create a continuous weld. This method is conducted underneath the flux, so that we can’t see it with the naked eye. It may be seen with X-ray photography.
Since the spiral steel pipe adopts the welding technology of submerged arc automatic welding, besides this kind 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, as well as the cleaning time is saved; the quality of the welding seam is high. In addition, it offers the necessary conditions for the delivery in the spiral welded pipe plant, in order that the production duration of the larger spiral steel pipe is guaranteed, so it is still popular.
1. The stress-bearing fluid is mainly used for the HDPE pipe fittings as the tube blank, and is also often spirally formed in temperature. It really is utilized 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 and the welding performance is also very good. After a number of rigorous scientific inspections and tests, the utilization situation is relatively safe and reliable. The solid diameter of the steel pipe is large, 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 natural gas.
2. General low-pressure fluid transport is principally 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 since 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 is 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 way of water, gas, air and steam along with other general low-pressure fluid transport Submerged arc welded steel pipe.
5. The pressure fluid transport is situated 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 selection of strict and scientific inspections and tests, the use of safe and reliable, PEX-AL-PEX pipe, transmission efficiency is also high, and will effectively save the laying pipeline investment. It really is mainly employed for the laying of pipelines connecting petroleum, natural gas, etc.