Selection of positive pressure pipes and pipe wall thickness.

When selecting the wall thickness of a pressurized pipe, tensile strength rather than yield strength is taken into account for the design pressure, because there is usually high-pressure gas or liquid inside such pipes, and these fluids possess elasticity which causes the pipes to expand. At this time, the stress acting on the pipe wall is mainly tensile stress; therefore, it is necessary to consider the tensile strength of the pipe material to ensure its safety. The yield strength of pipe materials refers to the maximum stress that the material can withstand before it begins to deform plastically. In pressurized pipes, however, the material generally does not undergo much plastic deformation; therefore, its yield strength is not a critical factor in determining the wall thickness of the pipe. Therefore, when designing pressurized pipes, more attention is paid to tensile strength rather than yield strength. .