The impact of negative temperatures on the condition of polyethylene pipes in bending
Abstract
The impact of negative temperatures on the condition of polyethylene pipes in bending
Incoming article date: 25.09.2015in modern conditions become widespread trenchless methods for the construction of pipelines. The positive features of their use include increased speed pipeline installation, reducing the volume of excavation, etc. Existing regulatory documents limit the bending of the pipe at low temperatures need to be tested in terms of their applicability to new grades of polyethylene. The aim of this study was to determine the minimum permissible bending radius of the track, the passage of which in the conditions of negative temperatures polyethylene pipes PE80 would maintain its strength characteristics. By using a mathematical model dependency of the elastic modulus and yield point are calculated from the temperature stresses in the walls of pipes of different diameters in bending under different temperatures. In order to establish empirical relationships voltage on the pipe diameter and the radius of its bend procedure is carried out function approximation method of least squares. Presented obtained graphic dependences. Using the values of the yield strength of the material at different temperatures were calculated bending radius of all dimensions. If the production of the track plow trenchless pipe-layer will be considered given the conditions, you will be provided with the necessary conditions for installation.
Keywords: plastic pipe, trenchless pipe layer, the stress-strain state, trenchless techniques, pipelining