In the later stages of hydrocarbon field development in the western region of Turkmenistan, due to declining reservoir pressure and increased water saturation, the number of oil wells employing mechanized recovery methods has been increasing year by year. A significant portion of these wells utilizes rod pumps.
At the Goturdepe and Barsagelmez fields, the number of wells operating with this method amounts to 155 and 136, respectively, with their share in total oil production at these major fields being 3.7% and 4.3%. Characterizing the operation of rod pumps, it is noteworthy that, unlike gas lift and plunger pumps, they function under more complex conditions. Considering their maintenance, installation, and energy consumption for both subsurface and surface systems, the primary objective is to enhance oil recovery efficiency and reduce production costs.
To ensure the reliability of equipment used in such wells (rods, pumps, pipelines, rod lifting mechanisms, and auxiliary structures), a key aspect is the proper selection and installation of these systems according to reservoir conditions, as well as monitoring the technological process at all stages of operation. Timely correction of malfunctions allows for adjusting oil production and preventing breakdowns.
Analysis of the performance of active rod pumps shows that 75% of such wells have an oil recovery coefficient that is 0.5–0.6 below the norm. The reasons why these wells produce no more than 3–4 tons of oil per day (with the exception of some highly productive ones) include the deterioration of reservoir permeability and filtration properties, as well as the presence of paraffin, soot, and other defects that hinder normal production.
It is important to note that measures to mitigate the impact of harmful gases and paraffin on pump performance are critical. For instance, gas entering from the reservoir fills a significant portion of the pump cylinder, disrupting its normal operation. When the gas content in oil exceeds 50 m³/m³, it has a negative impact on production.
As noted by Veyis AMANTAGANOV, a senior research associate at the “Nebitgazylmytaslama” Institute of the State Concern “Türkmennebit,” there are two main approaches to reducing the adverse effects of gas on pumps:
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Separating gas from oil at the lower part of the pump and diverting it into the annular space.
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Lowering the pump approximately 100–200 meters deeper into the oil column.
The challenge of addressing paraffin and soot in reservoirs composed of weakly cemented, soft formations remains relevant. There are mechanical and chemical methods available, but the task of retaining these substances at the bottom of the well has not yet been fully resolved. Nevertheless, some innovative devices developed for this purpose have shown partial success.
In addition, regular well performance inspections are essential. According to the results of such inspections, normal operation is maintained in 41.7% of wells, while in 7.3% of cases it is found that pumps are not filled with oil due to the presence of gas, in 11% of cases valve malfunctions in pumps are observed, in 5.4% the impact of paraffin is noted, and in 0.6% mechanical damage occurs.
To address these problems, appropriate measures have been proposed. Specifically, research aimed at improving well efficiency is being conducted by oil and gas enterprises such as “Galkynyshnebit” and other divisions.
In recent years, research and development activities in Turkmenistan and the implementation of new technologies have significantly improved oil recovery efficiency. The application of advanced practices and the optimization of equipment usage are opening new opportunities for increasing production volumes.
