V.N. Verjovkin, Dr. Sci. (Eng.), Chief Research Associate FGBU VNIIPO EMERCOM of Russia, Balashikha, Russia A.G. Markov, Cand. Sci. (Eng.), Senior Lector, markov01@yandex.ru Academy of GPS EMERCOM of Russia, Moscow, Russia
The method of protection of dielectric materials surfaces against electrostatic hazard is proposed. It allows for expanding the fields of application of the isolating materials and the products from them, ensuring implementation of their predominant qualities when using instead of metals, and eliminating dangerous shows of static electricity where they could be implemented unintentionally at application of earlier known methods. This decision is topical at reasonable replacement of the metal product (a wall of the vessel or tank) electrified by liquid (process medium), by the product from the isolating material with similar geometrical, technical and operational parameters keeping efficiency of protection by earthing means of the metal product. The up-to-date system of technical regulation provides for using criteria values of potential of the free isolating surfaces protected by cellular conducting structure or dissipative structures. However so far there was no model for their calculation considering dynamics of charging processes and the specified electrostatic loadings. The values are used which are related to current limit density as one of the electrostrength characteristics of mutually electrified objects, or as medium, in which electrization takes place. This method makes vitally important the area of technical regulation improvement, accumulation of data given about the values of density of electrization current of the vessels and equipment. Use of the specific electrical resistivity of the isolating material with the process medium is one of the important elements of the proposed methods. Effect of the methods of placement of the protective conducting contour coverings on electrostatic intrinsic safety of polymeric tanks and pipelines is considered. It is shown that protective efficiency of application of the grounded or dissipating electroconductive contours forming cellular structure depends also, on which side of the product wall they are placed.