Welding
Over the two years of observation of the connections on high -strength bolts in railway bridges, it was found that the length of the tariff bolts used for the corresponding measurements decreased by 10%, and in the first three months – by 7%, it believes that most of the preliminary voltage drop occurred due to plastic deformations developing to a small depth; These deformations occur in the contact planes between the puck and the nut or between the puck and the bolt head.
Welding steels is lit in the reports of Pom Phalutus (Czech Republic), Neumann (Germany), Tanaki and Hasechava (Japan). They concerned the technological issues of automatic welding under a layer of flux and in the environment of carbon dioxide and practical issues of welding of structures. Fundamentally new, taking into account the high technical level of welding, these reports do not contain. Only data on welding of bridge structures in Japan with a total weight of 5900 tons are interesting, some of which are of high strength NT60, which has a turnover of more than 50 kgkm2, shock viscosity from 15 to 25 kgm1SM2 for thickness from 18 to 32 mm at 0 ° C. (according to Sharpi). About 50 ° 0 seams of this bridge is formed automatic, 40 – semi -automatic and only 10% – manual welding. Part of the welding is made in the medium of carbon dioxide. They also used heating the welded elements.
For the first time, reports were presented to Congress in a new type of connection in metal structures – gluing. This species differs favorably with the bolted rivet and welded joints of Tyumen used in metal tiles, primarily because it does not weaken the material of the connected elements and thereby increases the efficiency of using the strength of the material.
In the Aurnhammer report (Germany), the results of some experimental studies of adhesive compounds reported that the first experiments in establishing static tensile strength were carried out on samples made of boiling steel with a 35-40-kgm2 strength limit.