2022   03   en   p.53-57 A.M. Hashimov, A.O. Orujov, M.A. Jamalov,
Some theoretical issues of formation and development of gas voids in cross-linked polyethylene insulation


It is of great practical importance to study the mechanism of formation of gas bubbles during thermal treatment in the production of medium and high voltage XLPE insulated cables. Experiments show that polymer insulation of cables is very sensitive to these types of defects. Taking this into account, the article developed a mathematical model of the development of gas bubbles in the polymer based on the theory of high elasticity and large mechanical deformation. Based on the mathematical model, the conditions for the development of gas voids were determined, and it was possible to find the critical degree of swelling. It was noted that the values obtained as a result of the theoretical calculations are very important in choosing the optimal technological mode in terms of obtaining homogeneous insulation.

Keywords: polymers,XLPE,voids,elasticity module, thermal treatment, mathematical model.
PACS: 61.80.Az, 82.35.Lr

Received: 13.09.2022


1. Azerbaijan National Academy of Science H. Javid ave., Baku, Azerbaijan, Az1143, e-mail:arif@physics.ab.az
2. Azərbaycan Technical University H.Cavid av., 25 Baku, Azerbaijan AZ 1073, e-mail:mehticamal@aztu.edu.az

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