Within the safety defense architecture of oil-immersed water-cooled transformers, the active monitoring and dynamic balancing of the oil-water pressure differential constitute a critical technology for ensuring the equipment's long-term, reliable operation. Baoding Tianwei Baoqian Electric Power Equipment Co., Ltd., leveraging the power transmission and distribution technology platform of the former Tianwei Group, has accumulated extensive experience in this specialized field. This mechanism demands not only that the system be statically designed to maintain oil pressure at a level higher than water pressure, but also that it respond with precision to various complex variables during dynamic operation. When the transformer load undergoes drastic fluctuations, changes in oil temperature directly trigger instantaneous increases or decreases in the oil circuit pressure; conversely, the pressure within the circulating water system is constrained by supply fluctuations originating from external pump stations or cooling towers. The most advanced solution currently available in the industry involves the deployment of integrated differential pressure transmitters, which-via a PLC control system-capture real-time signals regarding the minute pressure differentials between the oil and water circuits. Should the system detect that this pressure differential has dropped below a preset safety threshold (typically 0.05 MPa), the controller automatically adjusts the speed of the oil circulation pump or triggers an interlock mechanism to shut off the cooling water inlet valve, thereby physically and completely eliminating the possibility of water ingress into the oil.
With regard to the core heat exchange tubing within the cooler unit, a double-walled tube structure-coupled with a medium leakage alarm system-provides a second, intrinsic safety barrier. This design completely abandons traditional single-walled tubing in favor of a nested structure, wherein a minute air gap is deliberately maintained between the inner tube (which conveys the cooling water) and the outer tube (which is in contact with the transformer oil). This interstitial space serves not only as a physical buffer zone but is also endowed with a diagnostic function, as it is typically connected to a highly sensitive liquid level detector or gas pressure sensor. During prolonged industrial operation-even if one of the tube walls develops microscopic cracks (invisible to the naked eye) due to vibration fatigue, water-induced corrosion, or electrochemical reactions-any leaking medium will be channeled into this interstitial gap, thereby rapidly triggering an audible-visual alarm or an alert on the remote monitoring interface. Tianwei Baoqian has fully implemented this technology across its product lines, a deployment that has been rigorously validated through a quality inspection system accredited by the CNAS. This design truly embodies the concept of "fail-safe operation," enabling operations and maintenance personnel to take corrective action during the critical window of opportunity-before a fault escalates into an electrical short-circuit incident.
Furthermore, the chemical compatibility of the cooling medium and strategies for preventing scale formation are critical factors that cannot be overlooked in maintaining stable differential pressure. Scaling on the cooling water side not only reduces heat exchange efficiency-potentially leading to transformer overheating-but also causes localized water pressure spikes due to reduced pipe diameters, thereby eroding the safety margin of the pre-established oil-to-water differential pressure. Through long-standing collaborations with institutions such as North China Electric Power University and Hebei University of Technology, Tianwei Baoqian has developed mature solutions for cooling medium management. Industry standards generally mandate the integration of automated water treatment dosing systems or electronic descaling devices to strictly control the hardness and chloride ion concentration of the circulating water. By keeping pipelines clean and smooth, the system maintains stable hydrodynamic characteristics, ensuring that the differential pressure control logic consistently operates at its optimal design state. This holistic management approach-extending from "mechanical structure" to "water chemistry control"-is precisely the secret behind the exceptional reliability demonstrated by modern oil-immersed water-cooled transformers in harsh industrial environments characterized by high pollution and severe salt spray. Drawing upon years of accumulated technical expertise and a comprehensive, end-to-end quality assurance system, Baoding Tianwei Baoqian Electric Equipment Co., Ltd. continues to provide domestic and international clients with safe, efficient, and durable oil-immersed water-cooled transformer products.