Industry News

Welcome to this issue's popular science column. When you think of oil, you probably think of gas stations, cars, and fluctuations in international oil prices. But have you ever wondered what form these oil and gas, often called the "blood of industry," actually take deep underground? And how are they extracted scientifically?

In the field of global oil extraction, lifting technology, as the key driving force of crude oil from underground to the ground, has always been the cornerstone of industrial development. Among them, the lifting technology of the beam-type pumping unit and the lifting technology of the electric submersible pump have become the mainstream choices for oilfield production due to their wide application and reliable performance. The evolution of these two lifting technologies has not only improved the mining efficiency, but also demonstrated the intelligent transformation of modern energy equipment.

Whenever an oil well is unable to lift crude oil to the ground autonomously like a tired old man, engineers activate artificial lift technology. Gas lifting is one of the most commonly used methods. Does it count as artificial lift technology? The answer is very clear: yes, gas lifting is not only an artificial lift, but also an efficient technical means recognized by the petroleum industry.

Imagine that an oil mine that has been mined for many years is like a well that is about to dry up. When it cannot “carry” crude oil from the depths of the ground to the ground on its own, engineers will activate artificial lift technology to help. This kind of technology is not magic, but the crystallization of human wisdom-it uses external equipment to “pump up” the oil well and let the crude oil flow obediently. Today, let's take a look at how artificial lift works step by step.

To understand the reasons for the size difference, we must understand the working principle of the gas lift. As the mainstream artificial lifting method, the core of gas lifting is to reduce the density of crude oil by injecting high-pressure gas into the oil well. However, the “thrust” required for different oil wells is very different: Shallow wells may only require small compressors, while ultra-deep wells require truck-like giant equipment. The gas lifting device used in a shallow oilfield in Karamay, Xinjiang, covers an area of less than 10 square meters; In the deep-sea oilfield in Bohai Bay, the volume of similar equipment is comparable to that of a container-the size difference is directly due to the precise adaptation of manual lifting to well conditions.

​Continuing from the previous article, click to jump to questions 1-50! This "100 Q&A on Oil Production Basics (Part 2)" continues in a Q&A format, covering questions 51-100. These questions primarily cover oil well performance analysis, oil well operation monitoring, water injection and flooding operations, pumping unit and electric pump well maintenance, and the basic concepts and operation of Christmas trees and oil and gas transmission systems.

We have compiled "100 Q&As on Oil Production Basics," which uses a question-and-answer format to organize and summarize key knowledge points about oil and gas fields. This is Part 1, covering questions 1-50. The content covers core knowledge such as the basic concepts of oil and gas fields, production wells and oil production methods, pumping unit and progressive cavity pump operation, water injection and flooding methods, and oil well operation and maintenance.

Definition of Shale Oil： Shale oil refers to petroleum stored in organic-rich, nanoscale pore-bearing shale formations. It is the abbreviation for mature organic shale oil. Shale is both a source rock and a reservoir rock for oil. Shale oil exists in adsorbed and free forms and is generally light in weight and low in viscosity. It is primarily stored in nanoscale pore throats and fracture systems, distributed along or parallel to lamellae. Organic-rich shales generally accumulate over large, continuous areas in the center of a basin, are generally oil-bearing, and have a large resource size. Key factors in evaluating the "core zone" of shale oil include reservoir space distribution, reservoir brittleness index, shale oil viscosity, formation energy, and the size of the organic-rich shale. The successful extraction of shale gas provides a technical reference for shale oil extraction. "Artificial permeability" stimulation technologies, such as horizontal well volume fracturing and refracturing, are key technologies for the effective development of shale oil. Among shale oil resources, condensate oil or light oil may be the primary types for industrial production [6,11]. Condensate and light oil molecules have a diameter of 0.5 to 0.9 nm. Theoretically, they are more easily flowable and recoverable within the nanoscale pore throats of shale under high temperature and high pressure underground.

After exploration, drilling, and completion, the well begins normal production, and the oil field enters the production phase. Based on the needs of the oil field, the goal is to maximize the extraction of underground crude oil to the surface, increase well production and oil recovery, and rationally develop the reservoir to achieve high and stable production. This is called oil recovery.

During the operation of a pumping unit system, leakage is a common problem that affects production efficiency and equipment life. While "tubing leakage" and "pump leakage" are often mentioned, many people tend to confuse them. This article will systematically explain the differences between the two from four perspectives: definition, causes, impacts, and solutions, to help users quickly understand and diagnose the problem.