Oil production is accompanied by the impact of the oil-water liquid and the gas phase with the simultaneous effect of temperature and aggressive substances on the oilfield equipment. Changes in the physical and chemical properties of parts made of elastomers during the operation of progressing cavity pumps (PCP) affect the amount of tension and the adhesion of the elastomer to the pump body – the main operating parameters. Available in the scientific literature the results of precision and laboratory studies of rubber compounds show that the issues of the influence of operating conditions on the physical and chemical properties of elastomers are not sufficiently studied. A new approach to the research of the effect of butadiene-nitrile elastomers on the effects of various factors is proposed, using modern physical and chemical methods and modeling their effect under operating conditions. The elastomer research methodology includes tests: fluid resistance, static tension and compression, elastomer-to-core adhesion, friction and wear, dynamic thermogravimetric analysis, elastomer fracture kinetics, and surface micrographs. The methodology was tested by conducting test experiments. A significant quantitative change in the geometric dimensions, strength and adhesive properties was found when changing the influencing factors. For example, at an overpressure of 3.0 MPa, the swelling of the elastomer and the swelling stress on the depressions are 1.6 times greater than on the protrusions. At an excess pressure of 3.0 MPa, compared to 0.1 MPa, for example, on the protrusions, the swelling of the elastomer and the swelling stress are reduced by 2.6 and 2.1 times, respectively. It is shown that dynamic thermogravimetric analysis makes it possible to determine changes in the structure of the elastomer for different operating conditions. Conducting studies of elastomers according to the proposed method will allow us to assess the compliance of the elastomer with the conditions of its use, classify the causes of low operating times, minimize risks when choosing equipment and ensure high operating times for РСР for oil production, by predicting changes in the properties of the elastomer under operating conditions.
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