Welding

Ways of Welding

There are different ways of joint for types of material in different thickness, shape and ways, normally, we will have mechanical joint, chemical joint, metallurgical joint, but for metal material, mechanical joint and mechanical joint are the most common methods.

According to the joint method, welding can be roughly divided into three categories.

The fusion of base metal and base metal or the fusion and bonding of welding rod (welding material) and base metal; The use of mechanical friction, pressure, electric current, etc., so that the base metal melting and joint "crimping"; The "brazing" of a joint by using the material (brazing) required for the joint.
At the same time, for a variety of joint methods, there are a variety of welding methods, according to the base metal to be engaged and conditions and other factors, the use of appropriate welding methods.

The quality of "Welded product" are as follows.

● Complete correctly according to design dimensions.

● Has the required function and strength (or safety).

● The appearance of the welding part meets the requirements of the grade.

● The basic "weld quality" requirements required to produce such a high quality product are shown in the following items.

● No cracks or holes in weld bead.

● Weld bead waveform, width, height and so on uniform.

● The surface basically has no deformation, accord with the design size.

● Welding can achieve the specified strength.

● Distinguish between the use of "full penetration welding" or "weld joint" including "partial penetration welding" to obtain the required rigidity.

Inspection of Welding

In order to reduce welding defects and improve welding quality, it is very important to select materials and processes that match the purpose in welding design stage. However, even if the design is reasonable, if the defect occurs in the welding process, it will have a great impact on the quality. For example, bead defects can have a significant impact not only on appearance, but also on strength. In other words, the appearance defects such as dents, bite edges, overlaps, insufficient height, cracking (surface), bead bending, groove residue, arc abrasion are defects of welding quality.

In addition to visual inspection, there are also "magnetic particle detection (MT)", "penetration detection (PT)", visual system or laser displacement sensor detection and other methods.

Internal inspection of bead or base metal using ultrasonic or radiation.

Reasons to cause defect of welding

Airball, Impure compound, welding spatter, Less full melting of welding material, Cracking

YSY will provide high quality level of welding technology to control the quality, come to contact with YSY.