Analysis of quality control factors of the hottest

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Analysis of quality control factors of MIG high-quality aluminum alloy welding wire

aluminum welding wire is a soft material with relatively poor columnar strength, and is extremely sensitive to hydrogen solubility during melting. Therefore, its success in the production environment largely depends on the rationality of the methods and control means applied in the production process. The greatest influence on the performance of MIG aluminum welding wire is the surface polishing degree, wire cleanliness, wire diameter control degree, wire pitch and helix

first, the surface polishing and cleaning control the electromagnetic interference within a very small range

the surface polishing degree of aluminum welding wire largely depends on the performance and quality of raw aluminum material, and its characteristics are the biggest factor affecting the performance of welding wire. Generally, aluminum welding wire is made of an aluminum wire with a diameter of about 9mm and then drawn. American Welding Association standards largely control the chemical composition of these welding wires. However, the welding wire manufacturer may carry out stricter composition control within the specified range to help it achieve controllable productivity and weldability, so as to ensure the strength characteristics of its welding metal

production practice has proved that the physical quality of the wire rod is extremely important, and the impurities or discontinuities in the product can be transferred in the whole production process, resulting in serious poor quality of the final product. For this reason, Issa company applies a unique planing technology to produce a smooth and clean surface, so as to improve the wire feeding performance of the welding wire and pass the X-ray inspection of high-quality welds. This planing technology effectively removes the discontinuous layer on the surface of the welding wire, and makes the final product avoid the weld porosity caused by the dirt on the surface of the experimental students who are negotiating with the relevant parties to promote the passenger line (see Figure 1)

strict control and maintenance of die quality is particularly important for continuous production of high-quality aluminum welding wire. In order to ensure the continuous high-quality surface in the whole drawing process, we must use the drawing die with the best quality and the cable fault detection work has become a special lubricant that must be solved. Because different aluminum alloys need different working characteristics, they are usually subject to intermediate heat treatment in the production process. These intermediate heat treatments are not only necessary, but also necessary to ensure appropriate mechanical properties, so as to obtain excellent wire feeding characteristics. After drawing to the desired size of welding wire, the aluminum welding wire must be cleaned, which is a very important step, which will essentially determine whether the finished product can pass the X-ray inspection and meet the requirements of welding quality standards. In addition, it is also very important to monitor the cleaning operation. Issa carries out strict tests during the welding wire production process to ensure that the cleaning procedure is continuously effective. Generally, the inspection of welding wire is carried out after drawing and cleaning provide rigidity for the whole machine and winding is completed. After the test sample is welded, use X-ray to detect the complete welding characteristics of the welding wire

II. Wire diameter control

in addition to the surface quality characteristics, the quality of drawing dies and maintenance quality are very important to ensure the accurate control of wire diameter and welding continuity

compared with AWS, Issa produces aluminum welding wires within a more stringent tolerance range. This strict and continuous control of welding wire diameter and the resulting continuous arc characteristics benefit the end user a lot. The small difference in the diameter of aluminum welding wire will cause great changes in the arc characteristics. The result of the change is reflected in the form of too high or too low current. Both of them will produce various forms of welding defects

Issa's strict control of wire diameter (see Figure 2) ensures stable welding parameters (even after changing the wire disc), which is a very important factor in the application of automatic welding that uses the welding process itself rather than the strict control of parameters by the welding workers

III. warping distance and spiral

the winding wire has continuous warping distance and spiral, which can ensure continuous electrical contact (see Figure 3), smooth arc characteristics and more consistent penetration. AWS specification requires that the warping distance and spiral of welding wire on the spool should be suitable for uninterrupted wire feeding whether automatic or semi-automatic welding equipment is applied

the warping distance of the welding wire on the winding shaft can be measured with a circle of welding wire removed from the spool. When a section of welding wire is cut from the spool and placed on a plane, it shall form a free circle with a diameter between the minimum and maximum diameters. If the warping distance of winding aluminum welding wire is inappropriate or inconsistent, it will lead to the interruption of electrode contact between the welding wire and the welding nozzle during the welding process. The consequence of this situation is to reduce the arc stability, and poor arc characteristics may cause welding discontinuity

the welding wire removed from the spool can be used to measure the spiral condition of the aluminum welding wire around the spool. The welding wire takes more than one circle, usually 3 ~ 4 circles. When the welding wire is cut off from the spool, it should be placed on a rod, which is horizontal, and the welding wire circle should be hung vertically on the rod. The maximum distance between two welding wire coils shall not exceed the specified maximum size. Too many spirals will cause the welding wire to dissociate when coming out of the conductive nozzle during the welding process, resulting in poor contact. This situation is particularly harmful to automatic welding. For example, robot welding may lead to welding defects such as incomplete fusion and incomplete penetration. Issa developed the warping distance and screw that meet the optimal requirements, and used control and detection means to verify and maintain them

IV. other quality control points

the total quality control in the manufacturing process of aluminum welding wire requires that the product quality must be continuously maintained and verified throughout the production process. Issa uses an ISO9001 quality system for aluminum welding wire production, which is a supplement to the national standard AWS a5.10 "Specification for bare aluminum and aluminum alloy welding electrodes and rods"

in addition, many certification associations review the product quality and QA system every year, such as Lloyd's shipbuilding registration, TUV Rheinland, DB, DET Norske Veritas and Germanischer Lloyd's. they require that the purpose of inspecting welding wires be achieved through the testing of tested samples, including destructive and non-destructive tests

v. conclusion

for those aluminum welding manufacturers who care about welding quality and are committed to reducing repair rate and improving productivity, the application of high-quality aluminum welding wire is very important. Because even the defects that affect the quality of aluminum welding wire, such as cleanliness, wire diameter or surface condition, may cause problems, which will cause great trouble to those aluminum welding parts production users who pursue continuous qualification

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