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The most widely used mechanical oil extraction method worldwide is screw pump pumping, and the most common operational problem is that the pump does not fill up completely, resulting in low productivity. This incomplete filling occurs when the pump’s capacity exceeds the well’s production rate, or due to poor gas separation at the pump’s inlet; as a result, part of the pump’s discharge volume is lost due to gas interference. By eliminating this gas interference within the pump and controlling its operating time so that the pump’s discharge volume matches the amount of fluid flowing into the well bottom, efficiency can be improved and costs reduced. The specific methods to maintain a high production rate in screw pump oil extraction are as follows: 1. Acoustic level measurement should be carried out to determine the relative depth between the liquid production level and the pump’s suction inlet. If the liquid level is above the pump inlet, the well cannot be operated at maximum production. If gas interference affects the yield, the liquid level is above the pump inlet ； If low yield is caused by excessive pumping volume, the liquid level should be at or near the pump inlet. 2. The indicator gauge is used to determine the percentage of pump filling factor, and a comprehensive data acquisition system can simultaneously provide motor power and indicator gauge data. One of the main uses of a power diagram is to diagnose how a pump is operating and to analyze problems downhole. By using production fluid level measurement in combination with a P-V diagram, it is possible to determine whether the well is producing at its maximum rate, whether the fluid column height is greater than the pump suction depth, whether the pump is not fully filled, and whether free gas is migrating upward through the annulus around the casing. 3. Diagnose low-efficiency wells. The diagnostic method involves determining the overall efficiency of the pumping system, and this can be done by measuring the power input to the prime mover, determining the production pressure at the bottom of the well, and using accurate production test data. The overall efficiency of a conventional beam pumping system should be around 50%; if it is lower than this, its performance needs to be improved. Techniques to improve overall efficiency include maintaining high volumetric efficiency (matching the pump specifications to the injection volume in the wellbore, eliminating gas interference, and controlling pumping with a pumping controller or timer), as well as replacing oversized motors. 4. Downhole gas separation. Invalid pump operation is often caused by air interference, and can be diagnosed through acoustic level measurement and indicator diagrams. It is best to place the pump inlet below the fluid entry section; if it is placed above, a gas separator should be used. If the valve seat stub is located at least 10 ft below the bottom of the fluid inlet zone, effective gas separation can occur in the annulus, with the casing serving as the outer cylinder of the separator. However, the conditions in wells often do not allow the pump to be placed below the fluid entry zone, so an underground gas separator is considered. A conventional gas separator consists of a fluid inlet section (such as a perforated sub), an outer cylinder (such as a length of tubing with a plug at the bottom), and a liquid seal tube at the bottom of the pump. 5. Controlling the pump displacement can be achieved by adjusting four parameters: plunger size, stroke length, number of pump strokes, and daily operating time. Due to the high cost of removing the equipment, pumps that are not of the appropriate size are usually not replaced. The simplest approach is to change the configuration of the surface equipment, such as moving the traveling beam tie rod, in order to adjust the stroke length of both the surface unit and the pump ； Next is to replace the motor pulley in order to control the number of pump strokes. The issue of matching pump capacity to well production can be addressed by changing the daily operating time; the following devices can be used to control this operating time: dry run controllers, interval timers, and percentage timers. The air-pumping controller stops the pump if it detects that the pump is not fully filled. A timer controls the operating time of the pump; it is inexpensive and easy to operate. The duration of pump shutdown should be short enough so that the production pressure at the bottom of the well does not rise by more than 10% of the reservoir pressure. The operator can use 45 minutes per well to conduct the aforementioned measurements using sound waves, dynamometers, etc., in order to determine the well’s production capacity, the performance of downhole pumps, the operation of downhole gas separators, the load on sucker rods and beam pumping units, as well as the performance of motors. Through 45 minutes of analysis, operators can maximize well production while reducing operating costs.