All-welded plate beam welding of plate heat exchanger
In the manufacture of full and welded plate heat exchanger, plate beam welding is a key link to ensure the quality of equipment and its plate beam USES mostly less than 1 mm thickness austenitic stainless steel sheet stamping into plate of compound and into.
In the process of welding is easy to burn through, deformation and weld forming bad problems.
To the weld length in 2 000 mm above, is more difficult to eliminate such defects.
Main factors affecting the quality of plate beam welding plate, punching deformation, fault clearance between edge and the cutting burr, etc.
To eliminate these hidden danger, we must improve the positioning accuracy of the jig.
In this paper, a kind of precision positioning, convenient operation of the positioning fast loading fixture.
Structure and principle in using laser welding, TIG or MIG welding high degree of automation, such as welding way, as to the requirement of the automation of jig.
Most of the time control is realized by using pneumatic, hydraulic or electric elements to improve efficiency.
Long weld, when welding on the plate of the original size and demanding, for some special shape plate, the traditional jig is difficult to meet the requirements, such as flatness of dense ball bubble, due to the limitation of space position, pneumatic and hydraulic clamp in the direction of the weld length of precise complex operation, high technical requirements to the operation of the workers, weld repair rate is high.
Figure 1 is the author for all welding of medium plate beam and welded plate heat exchanger design of special fixture, the fixture is made up of top board, under the guide bush, conical guide pin, guide sleeve and the press table, etc.
This set of tooling with conical guide pin (
Implement a positioning, on the cone type guide pillar and guide sleeve inside the cavity is equipped with a small spring, spring can be achieved when the clamp down on positioning buffer, prevent the impact of plate damage, spring can make tooling flexible alignment, do the positioning.
In order to ensure the accuracy of positioning, in the middle of the upper and lower pressure plate also has three pairs of completely different plate pressure molding mould shape with the small module, to limit the relative displacement of plate.
So as long as make sure it is 4 conical guide pin positioning, plate can be precise positioning.
Its positioning accuracy for 6 000 mm in length on the wrong side of less than 0.
The card and replace panels, will be on board with the crane to lift, stay plate positioning, control crane down clamp in point move way, four conical guide pillar and guide bush cooperate can be completed under one card, each card takes less than 1 min, card process is simple, high efficiency.
When lifting with the light and protects the tooling quality strong nylon rope.
2 characteristics (
Protection plate beam, high welding when the welding seam quality parts outstretched jig 1.
5 mm, near the weld parts and tooling materials of different material QT42210, prevent welding welding slag splash in the beam and plate, at the same time also can heat spreading rapidly after welding, reducing heat affected zone, to prevent the overall deformation of plate beam.
Due to the high positioning precision tooling, in the case of welding specification to select appropriate welding seam without burning through, bite edge and molding bad phenomena, such as plate beam integral forming after deformation is very small.
Less investment, good compatibility with the fixture in the process of using do not carry too much load, so most manufactured Q2352A fixture, near the weld parts adopt strip and plate corrugated form the same cast iron.
Framework of different forms of corrugated plate, fixture, only according to replace the cast iron corrugated form small module of strip and the same as the pressure molding.
1 set of such investment framework, a variety of specifications plate welding can be completed.
Simple structure, good rigidity, good manufacturing technology of a complete set of jig no special structure, also does not have the big parts, simple structure, using truss in principle, in the middle of the two main layering with Angle steel welded on the structure of a triangle phase can increase the stiffness of the fixture, fixture deformation in the process of using.
Framework can overall or subsection welding, then processing as a whole.
3 the epilogue of this set of jig settled the whole beam and welded plate heat exchanger plate during the welding process positioning inaccurate, poor quality of weld, jig no compatibility and low production efficiency.
In a high degree of automation, the investment is small but it can realize accurate positioning, under the condition of improving the efficiency.