Welding Technology and Problems of 1.2mm-3.2mm TIG Welding Wire
1.2mm-3.2mm TIG welding wire welding process there are many ways to learn, today 1.2mm-3.2mm TIG Welding Wire manufacturers for everyone to introduce the welding, surfacing is the surface of the workpiece or edge of a layer of welding Wear, corrosion resistance, heat resistance and other properties of the metal layer of the welding process. Surfacing to improve the service life of parts, the rational use of materials, improve product performance, reduce costs have significant economic benefits. Different parts and welding electrodes to use a different surfacing process, in order to obtain a satisfactory surfacing effect. The most common problem encountered in surfacing is cracking, the main method of preventing cracking is to preheat before welding, to control the inter-layer temperature, and to cool slowly after welding. After welding to eliminate stress heat treatment. To avoid multi-layer surfacing, the use of low-hydrogen surfacing electrode. If necessary, the surfacing layer and the base material between the surfacing transition layer.
At present in the field of industrial production, the technical requirements for surfacing and operation of workers is very high, in practice not only to avoid cracking, and after welding the workpiece hardness, strength and surface smoothness, etc. to meet the national requirements, This requires companies to have a good surfacing equipment, so as to maximize the quality of welding after welding.
1.2mm-3.2mm TIG welding wire has a stainless steel 1.2mm-3.2mm TIG Welding Wire, stainless steel 1.2mm-3.2mm TIG Welding Wire is also a wide range of applications, 1.2mm-3.2mm TIG Welding Wire manufacturers to focus on you about the stainless steel 1.2 mm-3.2mm TIG welding wire.
Since the 1970s, China's consumption of stainless steel 1.2mm-3.2mm TIG Welding Wire has grown rapidly, rising from 3% of the world's stainless steel consumption in 1990 to 10-15% in 2000. According to statistics, in 1998 China's apparent consumption of stainless steel reached 1.3 million tons, in 1999 the performance of consumption reached 1.5 million tons; 2000 apparent consumption reached 1.65 million tons or more. According to the growth rate and development trend of stainless steel consumption in the past two years, it is predicted that the total consumption of stainless steel 1.2mm-3.2mm TIG Welding Wire in China will reach 2.3 million tons in 2005, which is the first in the world.
After years of domestic welding technology staff efforts to introduce foreign technology digestion and absorption of some joint venture efforts, the level of domestic stainless steel welding consumables have been greatly improved, but compared with foreign advanced level, there is a certain gap.
1.2mm-3.2mm TIG Welding Wire types are many, in the 1.2mm-3.2mm TIG Welding Wire related to the introduction, today we focus on the introduction of 1.2mm-3.2mm TIG welding wire preheating:
High-strength or high thickness of the low-alloy steel structure should be preheated before welding. The preheating temperature is related to the hardenability, plate thickness, restraint degree and hydrogen content of the steel. The project should be determined after the test. The recommended preheating temperature can only be used as a reference. Multi-layer 1.2mm-3.2mm TIG welding wire should be maintained when the temperature is not lower than the preheating temperature, but also to avoid the interlayer temperature is too high caused by adverse effects, such as toughness and so on.
Workpiece preheat to prevent cracks, reduce 1.2mm-3.2mm TIG Welding Wire and heat affected zone cooling speed, reduce welding stress and other important role. However, preheating deteriorates working conditions and complicates production processes. Low-alloy steel structure before welding need to preheat, should be based on 1.2mm-3.2mm TIG Welding Wire production practice and welding test results to determine.
Generally, when the carbon equivalent of the 1.2mm-3.2mm TIG Welding Wire base material is not less than 0.35%, the preheating should be taken into account; when the carbon equivalent is not less than 0.45%, it should be preheated. From the thickness of the consideration, the tensile strength of 500-550MPa low alloy steel, when the thickness of more than 25mm, should be considered for more than 100 ℃ preheat before welding. From the ambient temperature when welding, plate temperature below 0 ℃, the welding should be preheated. At this point can be around the application of welding within 80mm to about 150 ℃.
Can be used oxygen - acetylene flame or other heating methods, but requires 1.2mm-3.2mm TIG Welding Wire heating method does not affect the performance of the base metal. Preheating can be divided into local preheating and overall preheating. Partial preheating, the heating range should ensure that the weld on both sides of not less than 80mm. Preheat temperature is generally 100-200 ℃, when the steel strength level is high, structural rigidity, may be appropriate to improve the preheating temperature.