Does the creep rate of PE pipes increase in high-temperature environments?

In high-temperature environments, the creep rate of PE pipes does indeed increase significantly. Creep rate refers to the rate at which a material undergoes reversible deformation under prolonged stress. The impact of high temperature on the creep rate of PE pipes is mainly manifested in several aspects:
Firstly, high temperature markedly increases the thermal movement capability of polyethylene molecules. This means molecules are more prone to move and rearrange at higher temperatures, making the material more susceptible to plastic deformation. This increased molecular mobility leads to greater deformation and creep in PE pipes under high temperatures.
Secondly, high temperature lowers the glass transition temperature of PE materials, making them softer and more prone to deformation in high-temperature environments. Even relatively low stresses can cause persistent deformation in such conditions.
Additionally, high temperatures accelerate the relaxation of internal stresses within the material, further promoting creep behavior. Thus, phenomena like stress relaxation, which may be subtle at room temperature, accumulate over time and exacerbate creep in PE pipes under prolonged high-temperature exposure.
Lastly, the factor of time is crucial in increasing the creep rate of PE pipes in high-temperature environments. Typically, creep rate accelerates with time under high temperatures, indicating that PE pipes used over extended periods in such conditions may experience more pronounced and rapid creep.
Therefore, engineering design must consider the influence of high temperatures on the creep rate of PE pipes. Selecting appropriate pipe materials, enhancing materials, and implementing effective temperature control measures can mitigate or delay the adverse effects of high-temperature environments on pipe system creep, ensuring long-term reliability and safety of the system.