Analysis of the Possibility of Import Substitution in the Production of Sucker Rod Pump Cylinders at JSC “Neftemash”

Abstract

Chemical-thermal treatment is aimed at saturating the surface layer with elements that change the microstructure and properties of the surface layer of the part. The most common chemical-thermal treatment processes are carburization, nitriding and nitrocarburization. However, the use of these processes, despite increasing surface hardness, fatigue strength and wear resistance, also has disadvantages leading to loss of productivity. These include the duration of the chemical-thermal treatment process and, most importantly, the need for subsequent mechanical processing to eliminate possible deformations and warping when obtaining high-precision surfaces. For cylinders of sucker rod pumps operating under conditions of contact friction, dimensional accuracy after chemical-thermal treatment without subsequent mechanical treatment is of great importance. The article presents the results of experimental studies to test the effectiveness of the carbonitration process of rod pump cylinders, in order to ensure the longevity of the tubular parts of rod pumps at the Izhevsk enterprise Neftemash JSC and to search for possible ways of import substitution of German technology. As a result of experimental studies, it was found that in order to achieve the hardness required by the design documentation, it is necessary to either significantly increase the exposure time during gas carbonitration, or, to increase productivity and efficiency, conduct experimental studies using the process of liquid carbonitration in a molten salts of cyanates and carbonates; and also, the carbonitration process is certainly more effective than ion nitriding, which is currently carried out for 26 hours for cylinders of sucker rod pumps, since even with a holding time of 1.5 hours, the hardness results obtained are somewhat better than those of Chinese samples.