Speed of metal deformation of welded pipe sections in the process of natural tests

Abstract

It is clear that testing on Menage Charpey samples and other materials, which may not match the durability of pipe walls, does not reflect the real picture of visco-plastic failures, which does not allow the development of a methodology or model for predicting the residual life (failure-free) gas pipelines have a three-year term of operation. At the same time, theoretical and laboratory studies do not always provide sufficient evidence for nutrition, directly related to the reliability and trouble-free operation of pipelines. It is likely that in the laboratory minds of enterprises and scientific foundations, it is important to create and identify all the factors that characterize the growing and widespread use of metal in gas pipelines to represent nature. and testing of cutting gas pipelines with a length of 150-250 m. However, due to the technical complexity of their implementation, in the field Our minds will never again be faced with the need to identify a new set of registration parameters. In addition, the testing of highly labor-intensive procedures, including ensuring the safety of their implementation, requires large material and hourly costs. Serial testing of enclosed pipes in the drains of a specially lined landfill and cutting on this basis is quite consistent with the results of field testing of gas pipelines. Field testing of pipes allows for consistently inexpensive research when testing new types of steel and pipe designs. Therefore, laboratory data need to be verified and necessarily clarified based on the results of pneumatic testing of long-life pipe sections, so that at the present time there is an urgent need to combine laboratory and field tests pipes of the gas pipeline. Such testing is not widespread, but as a result of their experimentation, important information is taken away from the behavior and power of metal in the minds of vantagement and exploitation, those closest to exploitation. Full-scale testing was carried out at a specially trained test site for cutting pipes intended for the construction of main gas pipelines, which made it possible to determine the kinematic and dynamic parameters of the alignment of the model gas pipeline under operating conditions. importance and in minds as close as possible to the operational ones. Analysis of the results of the field (natural) tests is to confirm that from the moment of initiation of the collapse in the central pipe, the fluidity of the main crack (on both sides of the initiator) increases and increases distance approximately 2-3 diameters from the cut, reaching a maximum. Changing the fluidity after tightening the central pipe can be either symmetrical or asymmetrical to the cut in the middle pipe. This is due to the technique of carrying out the experiment and the formation of cracks, including displacements of the cutting edge in the middle of the pipe and various influences on the metal of the pipes in the zone of local tearing. The underlying regularity is that the maximum fluidity is not evident at the crack acceleration stage. It is necessary to note that in order to carry out the experiment, so that the achieved high fluidity of the structure is preserved when the top of the crack enters the final plot. This is ensured by consistent selection of the viscosity of the metal of the central pipe.