卧式柱塞泵曲轴的磁性液体密封设计*

卧式柱塞泵曲轴密封的可靠运行是曲轴轴承实现润滑与液压支架稳定供液的重要基础。基于磁性液体密封理论，设计一种单磁源梯度齿宽磁性液体密封结构，采用数值模拟的方法研究磁性液体密封结构的磁场分布特征，并分析不同密封间隙和转速对密封耐压性能的影响。结果表明：与均匀极齿宽度磁性液体密封结构相比，梯度极齿宽度密封结构平均耐压能力约提高11%；梯度齿宽密封结构中，随着极齿与永磁体距离的增大，各极齿耐压能力逐渐增强；随着密封间隙的增大，离心力引起密封失效的极限转速逐渐减小。

Design of Magnetic Liquid Seal for Horizontal Plunger Pump Crankshaft

The reliable operation of the crankshaft seal used in the horizontal piston pump is an important part for the lubrication of the crankshaft bearing and the stable supply of the hydraulic support.A magnetic liquid sealing structure with single magnetic source and gradient tooth width was designed according to the magnetic liquid sealing theory.The numerical simulation method was employed to study the magnetic field distribution characteristics of the magnetic liquid sealing structure.The effects of different sealing gaps and rotational speeds on the pressure resistance of the seals were analyzed.The results show that the average pressure resistance of the gradient pole tooth width seal structure is increased by about 11% compared with the magnetic liquid seal structure with uniform pole tooth width.In the gradient tooth width sealing structure,the pressure resistance capacity of each pole tooth increases gradually with the increase of the distance between the pole tooth and the permanent magnet.The limit speed of the seal failure caused by centrifugal force gradually decreases with the increase of the seal gap.