According to the algorithm of a developed comprehensive analytical solution method (CASM), a new cast high-temperature corrosion-resistant nickel alloy ZhS3LS-М has been developed for manufacture of all-cast nozzle appliances. The developed alloy is characterized by the high-temperature strength 975 40 s = 180-200 MPa at the level of the industrial non-corrosion-resistant alloy VZhL12E as well as technological weldability and corrosion resistance at the level of commercial weldable corrosion-resistant alloy ZhS3LS. 24 Ref., 11 Tables, 1 Figure.

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It is established that at application of earlier developed procedure of calculation of explosion treatment modes for pipe circumferential joints the extent of residual stress lowering depends on their initial level. In particular, at explosion treatment of pipes without the circumferential weld the induced compressive stresses are essentially lower than welding stresses, whereas the latter are practically completely relieved at treatment of welds of similar pipes by the same modes. Scatter of induced compressive stresses in pipes of different typesizes did not exceed the measurement error. Dependence of explosion treatment effectiveness on the magnitude of initial welding stresses was determined, which is of a nonlinear nature. Presence of such a dependence allows prediction of treatment results and correction of modes depending on requirements made of treatment results. Fundamental difference of the mechanisms of residual stress lowering at heat treatment and explosion treatment is shown. Reaching a zero stress level in the weld, being, as a rule, the weakest point of the structure, can be regarded as the optimum result of lowering residual stresses (RS) by postweld treatment. As shown in [1], application of calculation method to determine the modes of explosion treatment (ET) allows sufficiently effective lowering of RS in pipes of various typesizes. It is of interest to find out how close the calculated modes are to optimum ones, and to assess the possibilities of their correction when solving various practical problems. With this purpose additional verification of the calculation method was conducted on one-piece seamless pipes with the following typesize: 115 × 4 (steel 20), 115 × 10 (steel 17G1S), 160 × 6 (steel 17G1S), 216 × 7 mm (steel 20). This allowed eliminating experimental error introduced by making the weld.Explosive charges were mounted on pipe samples symmetrically relative to a certain diametral section plane, simulating the geometry of ET of pipes with finished circumferential welds. Calculation of experimental modes was conducted as it was done before for pipes with a weld, the center of which was conditionally located in the above section plane. Circumferential stresses after ET were measured in the same plane on the pipe outer surface.

hief ) , S. I . K u c h u k -Y a t s e n k o ( Deputy Editor-in-C hief ) , V . M . L i p o d a e v ( Deputy Editor-in-C hief ) , O. M . B e r d n i k o v a , Y u . S. B o r i s o v , V . V . K n y s h , V . M . K o r z h y k , I . V . K r i v t s u n , Y u . M . L a n k i n , L . M . L o b a n o v , S. Y u . M a k s i m o v , M . O. P a s h c h i n , V . D . P o z n y a k o v , I . O. R y a b t s e v , K . A . Y u s h c h e n k o ; V . V . D m i t r i k , NTUU

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