Generally speaking, all these welding innovations are given at the rubrics standart-unique of www.pogrebis-temp.com/unique.html. Here we repeat them, but with the accent, given to practical results of our achievements.

The unique welding repair of a crankshaft (it had the length 1,5 m and the main diameter 350 mm) was made on the big guillotine shears which could cut steel sheets with thicknesses up to 24mm. The matter was that this crankshaft had been broken at two parts, indeed in the zone of the mentioned large diameter, and its material was steel with nearly 0,35% of carbon. So, we prepared a special, able to be particular, device which had been made with high accuracy but did not prevent welding and other operations. Among them, of course, was pre-heating and very slow cooling of the crankshaft after its welding, with possibilities for using such welding methods as by stick electrodes and under flux. The repairing welding was conducted during 16 hours without interruption (because it was made many layers with careful cleaning of each weld before making the next one). Welding was made from different sides - by many turns.

When we discuss about problems - necessities and possibilities of welding without the filler material usage - when edge or corner seams are assembled with essential gaps between edges, some persons may ask: "What are the problems"? And these persons can bring such reasonable, at first sight, arguments against the mentioned problems:

  1. the modern computerized equipment (like punching) permits to make the majority of industrial goods with very high accuracy without errors of thin-walled parts assembling before their welding.
  2. there are a lot of different filler materials which may be used for the mentioned errors compensation.

We can object: punching and other accurate equipment are usually used in the mass production; not every thin-walled structure permits using a filler material. And our main counter-argument is that the gaps between edges can not be injurious for some structures, but - on the contrary - they may permit to produce some new original constructions (please, see the picture of our Chemical and petroleum industries) or to increase essentially the working properties of several specific goods. Let us see the edge weld of thin sheets made in the usual way and according to our invention (25). The top picture shows the usual (left) and the proposed (right) edge weld configurations. It is clear that in the case of usual configuration the plain of two edges contact has a role as a sharp knife which is provocative of the weld destruction while the stretch loads action.

Usual(left) and proposed(right) edge welds.

A radius shape of the weld root - in the proposed configuration case - improved such weld working properties. And the proposed weld configuration may be recommended for different thin-walled structures, especially if they work under inner pressure (some their examples are shown below). Of course, it may be extremely effective for constructions that work under cyclic and dynamic loads.

Some structures made with the proposed weld usage.

With our active participation the first sets - which permit to manufacture the above mentioned goods, edge welded bellows, filters, etc.- were designed and built They gave us possibilities, for instance, to produce:

The fragment of heat exchangers plates assambled with big gaps and shifts.


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