First, the welding stretch
On the sink market, the overall stamping (also known as the overall stretch or conjoined stretch), seam welding (also known as the end of welding) and butt welding three, both welding and butt welding are welded pots.
More common on the market is the production of welding technology, this process is mainly stretching two single-slot tank, and then press a panel, the two tanks welded to the panel, and then grinding process. Process requirements of the tank body stretching equipment is low, generally less than 500 tons of hydraulic equipment can be produced. But its welding and grinding process requirements are relatively high, the general domestic brands usually adopt manual seam welding, artificial grinding, tank and the panel at the junction is more rough, often Weld. Imported brands are CNC welding and CNC grinding, put an end to Weld, polish the seam is very smooth and beautiful.
The advantages of the seam welding process are as follows: 1. The shape of the sink panel can be diversified. The cost of the molds produced by the factory is small (the molds of the tank can be shared). 2. The sink panel can be made of brushed raw materials or embossed materials, which is beautiful and elegant. 3, can make a small angle R tank, close to square, with greater use of space.
The disadvantages of the seam welding lie in: 1. The welding process damages the stainless steel and easily breaks the austenitic molecular structure of the stainless steel to reduce the corrosion resistance. 2, welding and grinding process demanding, difficult to handle ordinary equipment. 3, material waste, high cost.
The whole drawing process (some also called one-piece drawing) is a process of directly drawing and forming two grooves on a piece of material through a combination mold. The process steps are relatively simple, but the equipment and mold requirements are high, stretching equipment needs more than 600 tons, or even up to 1,000 tons. Whether single slot or double slot, the processing of the tensile is generally divided into two tensile, but the overall stretch in the middle of the two stretching need to be a high-temperature solution treatment. Solution treatment (also known as annealing) is an important process of stainless steel processing, it is through the austenitic stainless steel (commonly known as 304 or 316) to 1050 degrees -1100 degrees, and then a rapid cooling process.
Stainless steel material in the processing or high temperature welding will cause changes in the molecular structure of austenite, increased stress (too rigid), corrosion resistance decreases. The solution treatment can be a good solution to this problem, the material restored to its original performance, restore its ductility and corrosion resistance. In fact, after the cold-rolled stainless steel from the mill must be carried out this process. (Some people say that "after this treatment of the sink, the natural weakened rigidity, sink hardness certainly reduced," the idea is wrong!).
The overall advantages of the drawing process are: 1, save material, cost savings. 2, from the design modeling can produce a shaped sink, beautiful and generous. 3, no welding, and the use of solution treatment to enhance the performance of stainless steel. The disadvantage is that: 1, sink mold into the high cost; 2, surface treatment difficult, not easy to make embossed, drawing and other surfaces. 3, R corner angle by the process can not be too small.
Butt welding process is to stretch two single slot, the cut flat two sides, and then welded together, and then the overall shape of the panel. Stretching equipment with the same requirements of welding sink, welding equipment selection of argon arc welding. The process of welding and grinding requirements are high, the domestic manufacturers use less equipment, thin material, the weld can not be handled very well, so you can often see the middle of the two grooves on the beam weld marks. Do a good brand crown Canada, the surface is also difficult to see the mirror to the weld. Domestic mainly for low-end market, low prices. The advantage is that the price is low, the process is simple; the disadvantage is the lack of aesthetics.
Three complementary processes, the mainstream of the two have their own unique strengths and weaknesses, in fact, in the design of the sink, some are suitable for seam welding process, some are suitable for the overall production process for stretching, in fact, suitable for consumers Is the best.