A weldment is a common metal structure suitable for fabrication by welding. Due to the variety of welded structural members, their classification methods are also different. For example, according to the manufacturing method of semi-finished products, it can be divided into plate welding structure, punching welding structure, etc; It can be divided into vehicle structure, hull structure, aircraft structure, etc. according to the structural use; According to the material thickness of weldment, it can be divided into thin-walled structure and back wall structure; According to the type of weldment material, it can be divided into steel structure, aluminum structure, titanium structure, etc.
There are many kinds of weldments, and their production processes and requirements are also different. The corresponding welding fixture and displacement machine are also very different in form, working principle and technical requirements. With the expansion of the application scope of welded structural parts and the improvement of the mechanization and automation level of welding production, the types of auxiliary mechanical equipment such as jigs and displacement machines used in the production of welded structural parts will also increase. According to the purpose of these auxiliary mechanical equipment or welding process equipment, they can be divided into four categories: welding fixture, welding displacement machinery, welding process combination machinery, and welding auxiliary equipment. The fixture used for assembling and positioning the workpiece is called the fixture; The fixture used for welding workpiece is called welding fixture, and the fixture used for assembly and welding is called assembly welding fixture.
They are collectively referred to as welding jigs. Welding jigs are divided into six categories according to power source: manual jigs, pneumatic jigs, hydraulic jigs, magnetic jigs, vacuum jigs and electric jigs.
