刷式封严磨损特性及其对泄漏影响的试验研究

Experimental Investigation on Wearing Characteristics and Effects on Leakage of Brush Seal

为了获得刷式封严磨损特性及其对泄漏影响,对间隙、过渡、过盈3种配合状态的低前挡板型小尺寸刷式封严进行了试验研究,试验测量了磨损量、泄漏量和转子轴心轨迹等。根据测量结果对各配合刷式封严的磨损特性和磨损对泄漏影响进行了研究。分析结果显示,在磨损特性方面:间隙配合状态下,磨损是局部磨损;过盈配合状态下,磨损发生在整个试验阶段,在试验初始阶段磨损较严重,且磨损较为均匀地发生在整个圆周;过渡配合的磨损发生在整个圆周上,且其磨损不均匀。在磨损对泄漏影响方面:间隙配合状态下,试验初始阶段小压差下磨损对泄漏的影响不明显,在中等压差0.2~0.3MPa时较为明显;过渡配合,磨损对泄漏的影响在小压差和中等压差下较为明显,大压差下不明显;过盈配合下,磨损对泄漏的影响发生在整个试验阶段且磨损对泄漏的影响随磨损量变化的减小而逐渐减小,试验的初始阶段磨损对泄漏的影响最为明显;试验的初始阶段,过盈配合时磨损对泄漏影响最大,过盈配合时次之,间隙配合时最小。

In order to get wearing characteristics and effects on leakage of brush seal, experimental investi- gation on small size of brush seal at clearance, transition and interference fit was made. Experiment tested the wear, the leakage of brush seal and the rotor＇s axis locus. The wearing characteristics and effects on leakage of wear were analyzed according to the test results. The results show conclusion of wearing characteristics as follows： the wear is concentrated wear when brush seal at clearance fit. The wear appears in whole test stage and severe wear appear at the initial stage of test and uniformly appears on whole circumference of brush seal when brush seal at interference fit. The wear appears on whole circumference of brush seal and is non-uniform when brush seal at transition fit. The effects on leakage of wear are not obvious at small pressure drop of initial stage of test and are most obvious at middle pressure drop which is 0.2 - 0.3MPa when brush seal at clearance fit. The effects on leakage of wear are obvious at small and middle pressure drop and are not obvious at high pressure drop when brush seal at transition fit. The effects on leakage of wear appear in whole test stage and become smaller with re- ducing of variation of wear and appear at initial stage of test when brush seal at interference fit. The wear of brush seal has the greatest effect on leakage when brush seal at interference fit, and middle effect on leakage when at transition fit, and the smallest effect on leakage when at clearance fit at initial stage of test.