How to make logging work more convenient after the pump is lifted?

When the pressure of a reservoir is such that it is insufficient to lift produced fluids to the surface, an artificial means is necessary to lift the fluids. “Artificial lift” is the general term for any means used to help lift production to the surface and can include methods such as injection of lift gas and downhole pumping.

artificial lift

Alternatively, the artificial lift can be viewed as a means of lowering the back pressure on the reservoir such that overall production volume can be increased. From this viewpoint, other technologies that may not necessarily help lift the fluids to the surface can also be considered to achieve the same goal of increased production volume due to the lowering of the pressure at the wellhead.

Logging operations are the use of geophysical methods and various logging equipment to collect acoustic, nuclear, thermal, and mechanical information of downhole rocks through sensors, and comprehensive evaluation and analysis of various information to evaluate oil and gas reservoirs and divide oil and gas.

The existing bottom mechanical fixation and top soft seal, bottom mechanical fixation rod-type pump, because the locking member in the fixing device is a claw structure, the screen tube is connected to the lower end of the outer tube.

When the logging operation is performed after the pump is lifted, the logging tool cannot pass through the screen connected to the outer tube. To complete the logging, the tubing must be lifted out, the outer tube should be lifted out, and the screen tube should be taken out. This not only increases operating costs but also wastes manpower.

logging operations

In order to make the logging operation easier after lifting the pump, Sanjack Group has developed a lock ring type mechanical fixed rod type sucker pump. The screen can be easily connected to the joint of the sealing and fixing parts at the lower end of the pump barrel.

When the pump is lifted, the screen and the pump are raised together, which facilitates the logging operation. This pump consists of an outer tube assembly, barrel assembly, plunger assembly, and lock ring bottom mechanical fixing device. The structure diagram is as follows:

downhole pumping

1 Out tube 6 Lower Joint
2 Barrel assembly 7 Lock Ring
3 Plunger assembly 8 Screen Tube
4 Lock ring-type bottom mechanical fixing device
5 Seat joint 9 Lock Sleeve


The working principle of the pump is: An annular groove is provided at the direct connection between the valve seat joint of the fixed part at the lower end of the pump barrel assembly and the lower joint. A lock ring is installed in the groove, and the lock ring and the lock sleeve on the outer tube form a lock ring type bottom mechanical fixing device, and the screen tube is connected to the lower joint.

Therefore, the screen tube and the pump barrel are connected together without connecting to the outer tube. This not only ensures the reliability of the sealing device but also facilitates logging operations.

This new type of pump has a compact structure, simple manufacture, reliable sealing and fixing, and convenient use and maintenance. It can realize logging operations when there is no lifting tubing string and greatly improves work efficiency.

The relevant information:

Well logging, also called geophysical logging, is a method of measuring geophysical parameters by using the electrochemical, conductive, acoustic, radioactive, and other geophysical properties of rock formations.

It is one of the applied geophysical methods. During oil drilling, well logging must be performed after drilling to the designed well depth, also known as completion electrical logging, to obtain various petroleum geological and engineering technical data as the original data for well completion and development of the oil field. Logging is traditionally called open-hole logging.

The second series of logging performed after the casing is run in the oil well is customarily called production logging or development logging. The development of production logging has generally experienced analog logging, digital logging, numerical control logging, and imaging. Four stages of logging.

well logging

According to the geological conditions, the comprehensive logging method can be selected reasonably, which can study the geological section of the borehole in detail, detect useful minerals, and provide in detail the data necessary to calculate the reserves, such as the effective thickness of the oil layer, porosity, oil and gas saturation, and permeability, etc. And research tasks such as drilling technology.

In addition, methods such as in-well magnetic surveying, in-well excitation intensification, in-well radio wave perspective and gravity logging can also discover and study blind ore bodies near boreholes.

Logging methods are widely used in the drilling of petroleum, coal, metal and non-metallic minerals, hydrogeology, and engineering geology. Especially in oil and gas fields, coal fields, and hydrogeological exploration work, it has become one of the indispensable exploration methods.

well logging operations

As an important method and technology for the exploration and development of oil and gas fields, logging has a history of nearly 80 years. With the advancement of science and technology and the development of logging technology itself, it plays a greater role in the entire process of oil and gas exploration, development and production, bringing higher economic benefits to the oil and gas industry.

Significant progress has been made in logging technology in the past ten years, especially after the 1990s. According to the traditional view, in oil and gas exploration and development, logging technology only does some quantitative or Semi-quantitative evaluation work has fallen far short of the needs of the rapid development of the oil and gas industry.

In today’s logging work, the theory, method, and technology for evaluating oil and gas reservoirs have been greatly developed, and the field of solving geological problems is gradually expanding.