Welding precautions of manufacturing stainless steel tanks
For the application of stainless steel tanks, it is required to have high airtightness and strong corrosion resistance to ensure that the material in the tank will not leak or corrode the tank, which is proposed for its manufacturing skill and welding process. A higher requirement. Especially when welding, there are a few things that need special attention.
1. When manual arc welding is used for stainless steel tanks, the welding current should be selected within the current range specified in the specification of the welding rod. Due to the large resistance value of the stainless steel, a section of the electrode near the clamping end is easily reddened by the resistance heat. When the welding rod is welded to the second half, the melting speed is accelerated, and the weld penetration is reduced, but the melting speed is too fast. It constitutes a disadvantage such as un-fusion. From the perspective of ensuring the corrosion resistance of the joint, it is also required to select a smaller welding current, reduce the welding heat input, and prevent the welding affected zone from overheating.
2. In the operation skill specification, it is required to select the narrow-track and multi-layer multi-pass welding skills. When the tank is welded, the welding rod should not be swayed as much as possible. This not only reduces the heat input, but also facilitates the precipitation of gas, and is also beneficial to improve the intergranular resistance of the welded joint. The ability to corrode.
3. The bottom plate may be deformed during the lifting process and must be corrected before laying. When laying the bottom plate, the bottom plate should be close to the backing plate, and the touched point should be firmly fixed, so that the backing plate and the bottom plate are deformed together.
4, the bottom plate of the floor should be welded once under the same temperature conditions. According to experience, due to the different temperature between day and night, shortening the deformation may be very fierce, which will affect the ovality of the bottom plate. Therefore, we must grasp the moment and the control of the temperature.
In addition, in order to prevent the hot crack phenomenon caused by welding during welding, it is also necessary to select a high-quality hydrogen electrode with a low carbon content, and it is necessary to have a slow arc collection to form a crescent-shaped arc-shaped shape. The distance of the arc extinguishing is better to grasp, and the next welding is to be performed before the last arc point becomes dark red. Generally, grasping these precautions can produce high quality stainless steel cans.