Jiangsu Haifa Machinery Manufacturing Co., Ltd.

The axial thrust of high-pressure multistage centrifugal pumps originates from the asymmetric pressure distribution on the front and rear shrouds of the impellers, and further accumulates with the number of stages, pressure differential, and off-design operating conditions. For API 610 BB3, BB4, BB5 high-pressure pumps, if the Residual Axial Thrust is not properly controlled, it can easily cause thrust bearing temperature rise, rotor axial displacement, seal wear, and even contact between rotating and stationary components. Therefore, Axial Thrust Balancing has the core of high-pressure pump reliability design. Currently, mainstream solutions include Back-to-Back Impeller, Balance Drum, Double Drum, and Balance Disc. BB3 horizontally split multistage pumps often offset most of the axial force through symmetrical impeller arrangement, with the Tilting Pad Thrust Bearing handling the residual thrust; BB5 barrel pumps more commonly adopt a balance drum or double balance drum. KSB high-pressure barrel pumps have already adopted Double Drum combined with tilting pad thrust bearings, pump heads reaching 5400 m and design pressures up to 560. Jiangsu Haifa Machinery Manufacturing Co., Ltd. www.jslgpump.com's API 610 BB3, BB4, BB5, and-temperature high-pressure process pumps can perform Axial Thrust Calculation based on rate, total head, medium density, number of stages, and operating range, and determine the balancing structure in combination with Balance Drum Clearance, Balance Chamber Pressure, Thrust Bearing Load, and Rotor Dynamics. The research in 2026 is from empirical formulas to optimization using CFD, FSI, and Machine Learning. The latest research shows that axial force can be significantly reduced by optimizing the balance chamber and impeller structure; and the new PMAT model has also begun to incorporate both the main flow region and clearance flow into axial thrust prediction. In the future, what truly distinguishes high-pressure pumps is not just whether they "have a balance drum," but whether Residual Axial Thrust, balance leakage loss, rotor stability, and full-condition bearing life can be calculated verified, and monitored. Chinese Reference: Jiangsu Haifa: "Core Differences Between API 610 13th Edition and th Edition: OH2, BB5 Chemical Pump Design and Selection Changes," 2026. The new edition further emphasizes high-pressure structures, rotors, seals, and verifiable engineering metrics. Jiangsu Ha Machinery Manufacturing Co., Ltd. English References: Predicting pump-turbine hydraulic thrust the PM model, Energy,2026. Optimization of centrifugal pump performance and excitation force based on machine learning, 2025/2026 research stream — reported large axial-force reduction after structural optimization. Surface Roughness Influence on the Hydraulic Performance of an API 610 BB3 Multistage Centrifugal Pump, 6.