I. Product Overview

The submersible linear motor (LMA) is a new type of core equipment for submersible pumping developed by Zhejiang Jikun Power Technology Co., Ltd. It is primarily used in LESP (Linear Electric Submersible Pump) systems, designed specifically for the pumping needs of low-yield wells, deep wells, highly inclined wells, and horizontal wells in oil and gas fields. This technology features high efficiency, energy savings, reliability, and the ability to operate under harsh conditions. It has obtained national explosion-proof certification (number: CNV24.1100X) as well as quality management system certification.

II. Innovative Structure and Adaptability to Operating Conditions 

This motor features an innovative design with a long stator and a short rotor, breaking away from the traditional design concept of a long rotor and a short stator. The magnetic steel rotor operates at the center of the stator coils due to magnetic levitation, ensuring no wear between the rotor and stator and significantly extending the motor’s service life. The optimal distance between the stator and rotor magnetic fields is 10mm, resulting in smoother operation, reduced vibration, and thereby indirectly prolonging the service life of the accompanying piston pump. The motor stator and rotor are completely immersed in oil during operation. They can withstand high temperatures of 60–120°C and pressures of 10–30MPa. They are resistant to acid, alkali, and salt corrosion, enabling them to operate stably under various harsh industrial and mining conditions, including those with sand, gas, wax formation, or heavy oil. 

III. Characteristics of Core Components 

The mover assembly and the stator’s internal support guide sleeves form a friction pair. The motor stator generates a uniform magnetic pulling force around the mover, ensuring that the mover remains centered during operation and resulting in extremely low wear rates. The mover’s magnetic steel is made of high-temperature radial magnetized steel that can withstand temperatures up to 180°C. With the same motor diameter and length, this design provides twice the thrust compared to traditional designs, making it more suitable for deep-well operations. 

 The motor seal features a ring-shaped cascade-adjustable sliding seal structure, which provides superior sealing performance in harsh environments such as high altitudes. Its lifespan is 2-3 times longer than that of conventional seals. The breathing mechanism is made of PEEK material, and its unique elastic design enables automatic pressure balance inside the motor. 

IV. Technical Parameters

V. Working Principle

The submersible linear motor converts alternating current into mechanical energy, which is then transmitted downhole via cables. Under the effect of electromagnetic induction, the mover moves up and down reciprocally, in the same direction as the up-and-down motion of the plunger in a piston pump. The pump and motor are connected through oil pipes and submerged at the bottom of the oil layer within the well casing. The motor’s reciprocating motion directly drives the pump plunger to move up and down, thereby lifting the oil.

During upward movement, the plunger valve opens while the upper fixed valve closes, allowing the liquid inside the pump to flow towards the wellhead. During downward movement, the plunger valve closes and the upper fixed valve opens, enabling the liquid at the lower part of the pump to continuously be delivered to the wellhead. This results in efficient and stable operation.

VI. Application Scenarios

This motor is suitable for high-angle wells, horizontal wells, and vertical wells. It is compatible with various types of plunger pumps and is particularly ideal for deep-well production in low-permeability and small-bore wells. The daily oil production volume can be adjusted within the range of 0.1 to 10 m³/d (when the pump is installed at a depth of 1800 meters). This makes it an affordable solution for low-yield wells and the redevelopment of abandoned oil wells. 

It also possesses the function of jet flow unclogging and increasing production. Through the reciprocating motion of the actuator, a jet effect is generated in the balance chamber, which cleans the perforation openings of the casing. This enhances the oil well’s fluid delivery capacity. The technology has been successfully applied in numerous oil and gas field projects both domestically and internationally, significantly improving production efficiency and reducing operating costs.