METHOD OF LONG-TERM CORROSION-MECHANICAL TESTS OF METAL OF GAS INDUSTRY PIPES.

The resistance of the metal of gas industry pipes to hydrogen-sulfide (sulfide) cracking is usually evaluated on the basis of the results of long-term corrosion-mechanical tests on cylindrical specimens (diameter 6 mm) in the conditions of uniaxial tensile loading generated by the force constant with time. This paper proposes that it is more advantageous to evaluate this on semicircular specimens compressed or tensile-loaded at the ends with force P. Depending on the direction of applied force, tensile stresses can be generated on the outer or inner surface of the specimens. Consequently, application of the semicircular specimens instead of cylindrical ones makes it possible to reduce the deformation force, required for developing the given stress, by an order of magnitude or greater. Another advantage of the semicircular specimens is the fact that the magnitude of stresses can be controlled on the basis of the displacement of the end sections of the specimen, DELTA .