Swinging Water Injection Targets SWIT

With increasing wells connected to central facilities, it is hard to manage water flood using traditional technique. Therefore, a novel control concept named Swinging Water Injection Targets (SWIT) was developed in PDO to manage the challenges and satisfies both surface/subsurface requirements. The objectives of SWIT are: Maximize water injection well compliance. Minimize oil deferment due to water disposal restriction. Automated system that manages the variations in produced water flow with minimum interventions. SWIT concept is using the tolerance of ± 20% of desired injection target (Compliance limit) for each water injection (WI) well. So rather than having a fixed target, a minimum and maximum injection flow are giving to each WI well flow controller. Those range are provided by subsurface to ensure minimal impact for the rate fluctuation. The injection flows are driven by WI header pressure controller. When the produced water, the WI header pressure increases then the pressure controller to control the pressure asks all WI wells simultaneously increasing their injection flow at the same relative portion (Optimized distribution). Also, when the produced water decreases all WI flow starts reducing in the same way. SWIT concept proved success in PDO and it became a standard. It was first introduced in small field. Later, it was replicated across the company fields. The biggest scale implementation was in a cluster with more than 500 WI wells. Previously, in that cluster the WI header pressure was fluctuating indicating issues with water balance. Many manual adjustments were required to manage the situations when the produced water is more than the injection demand by closing oil producers leading to a considerable deferment due to water disposal restriction. Also, when the supply water is less than injection demand many WI wells start under injecting leading to low injection compliance. After SWIT was introduced in the cluster and all injectors started swinging in harmony via automatic control, it managed to balance the water system (controlled WI header pressure) regardless of the variation in produced water production. This resulted in increase of WI compliance by 5% after implementation. As SWIT optimized the water distribution to the injectors, roughly around 50 m3/d of additional oil production was achieved. It also minimized deferment from disposal restriction to a minimum level. All of this without the hustle of manual interventions.

Implementation of Fuzzy Logic Controller for Pressure Sensor Calibration Chamber

Atmospheric pressure is a weather element that must be observed in the field of meteorology. Electronic barometers, aneroid barometers, mercury barometers are generally instruments for atmospheric pressure measurement. The barometer must be calibrated periodically to ensure the performance of the instrument. To achieve the best target uncertainty during calibration, besides using an accurate primary standard barometer, a stable pressure controller is also needed. Pressure calibration media using a pressurised test chamber is more beneficial due to its capability to accommodate all types of pressure sensors. However, pressurise test chamber still requires an operator to control and stabilise pressure inside the test chamber. In this study, fuzzy logic has been programmed into a microcontroller to control the solenoid valve and vacuum pump for regulating air pressure inside a pressurised test chamber automatically. Fuzzy logic changes the solenoid valve states periodically by varying the opening and closing times. The final result of this study is a comparison between the calibration results using pressure controller with fuzzy logic and without fuzzy logic with the same primary standard and unit under test. The result of expanded uncertainty without a fuzzy logic controller is 13.06 hectopascal. Meanwhile, the pressure calibration process using fuzzy logic to control pressure in pressurised test chamber achieve 0.09 hectopascal of expanded uncertainty in 1000 hectopascal pressure value with coverage factor, k=2, and confidence level of no less than 95 %.

Design of Manifold with Pressure Controller for Automatic Exchange of Oxygen Gas Cylinders in Hospital

The regulation and supply of oxygen as one of the medical gases in the hospital is important to ensure the availability of these gases for the survival of patients. The regulation of oxygen gas in hospitals usually uses a piping system with manifolds. The manifold will monitor the oxygen gas pressure on each tube. Manifold systems that are widely used in general can only monitor pressure but cannot perform an automatic exchange on gas cylinders if the pressure is under the permissible conditions. The manifold system design developed is equipped with pressure monitoring for automatic exchange of oxygen gas cylinders using pressure sensors and microprocessors. The test results of the system using regulator and barometer comparisons showed the percentage value of sensor pressure accuracy of 96.92 percent and 97.16 percent. At pressure below the limit of 285 KPa manifold can perform the exchange of active gas cylinders automatically. These results show the manifold design built can work quite well.

The optimization of pressure controller for deep earth drilling

Obtaining samples of deep in-situ conditions is first step to explore the mysteries of the earth requires. In view of the current problems of insufficient pressure maintaining capacity of the existing equipment, we independently developed the in-situ fidelity coring system and designed the osmotic pressure controller based on the geometry of square cover. The finite element method is used to analyze the pressure maintaining capacity of the pressure controller. It is found that it would produce large deformation and stress concentration when the pressure was applied on, resulting in low pressure maintaining capacity. Then the structural optimization schemes of conical sealing contact surfaces with 25?, 35?, 40?, and 45? apex angles and spherical sealing contact surface are proposed, and the spherical contact surface structure is found to be optimal. Finally, the material is optimized, and a higher strength material such as 45CrNiMoVA alloy is used. Based on the pressure controller with spherical contact surface, the pressure maintaining capacity increased to nearly 70 MPa. The research results obtained in this paper provide the basis for the development of the coring system, the deep exploration of the earth and the establishment of rock mechanics theory.