Basic principles and requirements for welding tool design

Welding tooling design is one of the important contents of welding production preparation tooling. The quality of tooling design has a direct impact on production efficiency, processing costs, product quality, and production safety. To this end, we must consider several basic principles and requirements when designing welding tools.

(1) Welding products are always composed of more than two parts. For reasons of convenient welding or easy to control deformation, assembly and welding of more than two passes may be completed after welding, or welding while mounting; assembly welding After it becomes a whole connected permanently, the volume and weight are greatly increased, the structure is more complicated, and the designed tooling is adapted to this situation. The welding sequence has a great influence on the deformation of the workpiece. When designing the welding tooling, the parts with low accuracy requirements and the parts with high accuracy should be welded first to ensure the main accuracy requirements of the workpiece.

(2) During the local heating process during welding, welding stress and deformation will inevitably occur. When setting the rotating type welding positioner and clamp, full consideration should be given to the direction of welding stress and deformation. Generally, the expansion and contraction deformation in the plane of the weldment is not limited, and it is allowed to shrink freely by leaving a shrinkage margin; angular deformation, bending deformation, or wave deformation are controlled by a fixture, and sometimes anti-deformation measures are also taken by the fixture. When the welded joint is in a hot state, the deformation of the weld due to its own gravity cannot be ignored. It is also necessary to ensure that the workpiece is easy to take out when the stress after welding is large. In order to facilitate assembly and retrieval, under the premise of ensuring the main accuracy requirements of welding, the individual joints participating in welding can be under-positioned, or can be positioned and not clamped. For some workpieces with low accuracy requirements and indirect positioning (such as Stiffeners) can be left unpositioned.

(3) Different welding methods have different requirements on the structure and performance of the tooling. The manual arc tooling generally does not require strict speed of movement, and even does not require the workpiece to be turned. The tooling for automatic welding generally positions the welding head. There are higher requirements for accuracy and smoothness of movement, and the welding speed can be adjusted in a wide range; welding methods using electricity as a heat source generally require the weldment itself to be an electrode in the welding circuit, which may require welding For the function of fixture or insulation, when the welding current is large, the conductive part also needs to take heat dissipation measures.

Heavy Duty Positioner

(4) For manual fixtures and mobile tooling, reduce weight as much as possible while ensuring sufficient rigidity.

(5) Try to keep the weld in the flat welding position, because flat welding is easier to obtain high quality welds than other positions, saving time and effort. Weld all welds or joints on the fixture as much as possible, and at the same time, the number of inversions of the workpiece to be welded is small.

(6) The functional design and modeling design of tooling must determine the welding equipment tooling suitable for the human body from the perspective of ergonomics and various human factors. For example: whether the designed tooling is suitable for the sitting or standing position of the welder, whether the arrangement of the fixture and the welding position are within the optimal operating range; whether the welding sequence of the assembly, in addition to meeting the requirements of the welding process, forms a flowing action track, The handle is comfortable to handle, easy to apply force, and the operating force does not exceed the limit of human force.