The innovative development by Perm scientists will extend the lifespan of oil extraction equipment.

Easily extractable oil in Russia is rapidly declining, making it essential to develop new fields, including hard-to-reach reserves, to meet the demand in both export and domestic markets. Currently, these reserves are estimated at around 3.4 billion tons. However, the extraction of such resources requires significant investment and the implementation of advanced technologies. One promising type of equipment for extracting oil from deviated and side-drilled wells is rod pumping units with cable rods. These units are positioned at points of high curvature to connect the pumping unit with the pump. While the equipment is highly efficient, it can fail due to unacceptable bending caused by sagging in the rod string, leading to a complete breakdown of the system. Researchers at Perm Polytechnic University have proposed a new method for securing the cable rod in the curved section of the well, ensuring it remains straight and enhancing the operational reliability of the equipment.

2025-01-17 10:00:21https://naked-science.ru/article/column/oborudovaniya-po-vykachke

The article has been published in the journal "Current Issues in Improving the Efficiency and Safety of Mining and Oilfield Equipment Operations." The research was conducted as part of the strategic academic leadership program "Priority 2030."

To extract oil from inclined wells and wells with side branches, a pumping unit with a cable rod is actively used. This system serves as an insert within a standard column of pump rods and is installed at points of significant curvature. It can be envisioned as a flexible, inextensible heavy thread that hangs in the well's space between the pumping unit and the downhole pump. The primary function of this component is to transmit reciprocating motion to facilitate oil extraction.

When operating wells under complicated geological and technical conditions, it is possible to relieve the load on the pump rod column. The cable rod used in this context experiences compression, which can lead to cable failure, malfunction, breakdowns, downtime, and ultimately, equipment repairs. On average, this reduces the operational performance of pumping units by half, necessitating equipment shutdown and the costly replacement of the pump rod.

Scientists at Perm Polytechnic University have discovered a solution to this problem by securing the cable rod in the correct position using specialized devices known as centralizers.

"Their design should consist of a banded sleeve with external end stops, which are attached to the cable rod and ensure its straight alignment. They are installed in locations where stability of the rod is critical under maximum compressive loads," comments Anna Ivanchikova, senior lecturer at the Department of Mining Electromechanics at PNIU.

"According to our methodology, centralizers are placed at the point of maximum deviation of the cable rod from the well trajectory. The required point is calculated using mathematical equations. The next installation point is determined along the segment from the already installed centralizer to the bottom point of the rod, and so on," explains Valery Zverev, associate professor at the Department of Mining Electromechanics at PNIU and candidate of technical sciences.

With the installation of centralizers, the cable does not adopt a curved position within the column.

The method proposed by the scientists at Perm Polytechnic ensures the stability of the cable rod during suspension, preserves its operability, and extends the lifespan of well equipment. This significantly reduces costs associated with extracting hard-to-reach oil in Russia. The polytechnic researchers have already filed a patent application for the invention, which is currently under review.