During the long period, the problem on increasing strength of sucker rods used tor oil extraction in deep wells has been solved in a wide choice of new direction of alloyed steels. However, research in this direction could not give a significant effect due to the increased sensitivity of alloy steels to surface damage caused by corrosion and other possible causes. Sucker rods used in oil extraction operate in difficult conditions, sяubjected Io the simultaneous action of the corrosive medium an alternating voltage. Clippings sucker rods pose significant problems and as a consequence, leads to a decrease in oil production.
Furthermore, the use of such rods will significantly reduce the weight due to the reducing of the column diameter of sucker rods on one and sometimes two steps.
But previously developed single-brook machine had low productivity and increased the complexity of the quenching process of rods. The disadvantage of this installation is the impossibility of the simultaneous processing of multiple rods and low productivity of the heat treatment process.
Therefore, with the purpose to eliminate above-mentioned deficiencies. Institute has developed a new generation of thermal treatment installation of the finished rods – six-brook machine in the early of 80 years. Automation process of heat treatment of rocker bars, increasing of productivity and reducing of labor intensity has been provided in this machine compared to its analog.
Institution and met the requirements of GOST related to the rods and was installed on the territory of the “Ocherskoye Machine-building Plant” of Russia and in a plant named after “Lieutenant Schmidt” in Baku, Azerbaijan.
In order to eliminate the above-mentioned shortcomings a new type of heat treatment installation of rods was developed with fixed portals, on which inductors are fixed with sprayers and mobile platform In this apparatus, each spindle was connected to the threaded sleeve, which is moved along the spindle by means of springs and keys mounted on the spindle.
Installation Is made in the pilot plant of Machine-building and Technological Institution and met the requirements of GOST and has been installed in a plantnamed after “Lieutenant Schmidt” in Baku. Azerbaijan.
In the early of 90 years, by request of “Lanchzhousk” plant of general engineering (People Republic of China), Institute has developed and produced a more modem installation of rods heat treatment that meets the requirements of GOST. The Installation was made and accepted by the customer at a pilot plant of Machine-building Technological institution in Baku, Azerbaijan. In connection with the collapse of the USSR the installation was not completely delivered to the customer in China. The disadvantage of this setup was that it did not fulfill the technical requirements of the Specifications of the American Petroleum Institute on sucker rods. Furthermore, after passing the finished rods, the heat treatment process has been observed by a slight deviation of geometrical sizes of nipple threads and worsens its appearance.
Heat treatment of the rods allows a uniform over the entire length of the bar fine-grained structure and high-end properties. However, heat treatment (normalization, improvement, etc.) does not eliminate the sucker rod breakage during operation.
One of the most promising methods of hardening sucker rod is surface hardening rods with high-frequency (HDTV). Research of Machine-building Technological Institution has shown that during the surface hardening, corrosion - fatigue strength of sucker rods has Increased by more than 2-fold and significantly increased the strength of stainless steel rods. But induction surface hardening of sacker rods is a complex technological challenge in a production environment as the sucker rod with a length of 8 m has a diameter of 16-25 mm.
In order to address this problem, the Institute has created a special machine for surface hardening of sucker rods with the engine generator in the mid of the 70s year.
The machine is made by the experimental plant of Machine - bulling Technological Institution and met the requirements of GOST related to the rods and has been installed in a plant named after “Lieutenant Schmidt” in Baku, Azerbaijan.
The rod Is heated and quenched on this machine with a horizontal arrangement, the depth of the hardened layer is 1.8 ÷ 2.8 mm depending on the diameter of the rods.
Machine - budding Technological Institution has developed a new generation of thermal treatment installation rod blanks (without mechanical machining) In 2013, which meets not only the requirements of GOST but also demands of API Spec. 11B. The heat treatment process is fully automated. A source of high-frequency current is modern transistor controlled generators. Billet rods (without thread) were mounted on a movable platform, pass through the U-shaped inductors having vertical movement on the portal. As a result, quenching of head and body bars has happened in a continuous rod - sequential mode. The technical Indicators of the recently developed installation is much higher than their predecessors in the field of improvement of the cooling system and other devices and mechanisms. Unloading process is also automated, as its result manual labor has been reduced to a minimum.