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Structural design and sealing performance optimization of hose clamps: from finite element analysis to multi physics field coupling researchKeywords: hose clamp structure design, sealing performance, finite element analysis, multi physics field coupling abstract The sealing failure of clamps is one of the main causes of pipeline leakage. This article takes a certain type of automotive engine cooling pipe clamp as an example to analyze the key technologies for optimizing its structure and improving its sealing performance. 2.1 Sealing defects of traditional clamps Unreasonable toothed structure: Excessive tooth angle (>60 °) can cause local crushing of the hose, while insufficient tooth angle (<30 °) can lead to slipping and leakage. Insufficient screw locking force: When manually tightened, the torque fluctuates greatly (± 30%), making it difficult to ensure consistent sealing pressure (e.g. target value 5N · m, actual value 3.5-6.5N · m). 2.2 Structural Optimization Design Biomimetic tooth design: Drawing on the microstructure of lizard foot pads, the clamp tooth shape is changed to a "trapezoidal+serrated" composite structure, increasing the contact area by 40% and the friction coefficient from 0.3 to 0.5. Self locking screw mechanism: adopts a double nut+spring washer structure to eliminate thread clearance, and can still maintain a torque attenuation rate of<5% under vibration conditions (10g acceleration). 2.3 Sealing Performance Simulation and Experiment Finite Element Analysis (FEA): Simulate the deformation of the clamp under a pressure of 0.5MPa using ANSYS Workbench, optimize the toothed height (from 1.2mm to 1.0mm) to reduce plastic deformation of the hose. Multi physics field coupling experiment: The leakage rate was tested under high temperature (120 ℃), high pressure (2MPa), and medium (ethylene glycol) environment. After optimization, the clamp leakage rate was reduced from 0.1mL/min to 0.01mL/min. 2.4 Standardized Testing and Certification SAE J2064 standard: Simulate cold and hot cycles from -40 ℃ to 150 ℃ (1000 times), with a clamp torque attenuation rate of less than 10%, and leak detection through helium mass spectrometry (leak rate<1 × 10 ⁻⁹ Pa · m 3/s) for sealing. DIN 73378 certification: Passed 100000 dynamic fatigue tests (frequency 5Hz, amplitude ± 2mm), with no breakage or looseness of the clamp. conclusion Structural optimization requires a combination of simulation and experimental verification. By designing biomimetic tooth profiles and self-locking mechanisms, the sealing reliability and durability of hose clamps can be significantly improved. |