The Study About Behavior Test Of Three Types Of Mechanical Seal Rings With Different Face Structures

In order to improve sealing performance and the mechanical seal face friction pair lubricated conditions. People put surface modeling technology for mechanical seal mechanical seal to achieve zero-leakage and non-contact operation. The most widely researched ones are upstream pumping mechanical seal and seal with micro pores. However the two mechanical seals also have some shortcomings:Dynamic pressure of pumping groove mechanical seal is not strong. And leakage problem of cavity seal has not been solved; besides, serious wear and tear may generate under larger pressure condition. To solve these two problems, seal with micro pores and pumping grooves together on the ring face was developed to simultaneously achieve zero-leakage and non-contact. Study about it both on theory research and behavior test is under taken.Mathematical models of groove modeling and pore modeling were established based on hydrodynamic lubrication theory. Numerical solution method is introduced to solve this mathematical model. Refer to the optimized design results of parameters about groove and pore. Numerical simulations on groove modeling, pore modeling and groove-pore modeling were carried out separately by CFD software which named Fluent.Firstly, it is shown form the simulation result of upstream groove ring that a certain hydrodynamic pressure exists in groove area. And the distribution of the whole fluid pressure is more concentrated in the end of the groove which suggests the ability of keeping leakage out.Secondly, it is shown form the simulation result of pore ring that hydrodynamic pressure exists over and around the pore. And the distribution pressure at the bottom of pore is low which implies the risk of capitation effect.Thirdly, It is shown form the simulation result of groove-pore ring that the distribution of groove-pore ring is more equally than pure groove one.Behavior test was carried out so that advantages and shortages of every face modeling could be compared. Two typical types of laser surface texturing seals-seal with micro pores and seal with micro pores and pumping grooves together on the ring face were tested on seal ability and frictional behavior, contrasting with non-texturing seal. Conclusion could be drawn according to the result of the test as follows. On the one hand, it is shown that, the two types of texturing seals have excellent sealing and lubricating property. Specifically, seal with micro pores has comparatively better sealing and lubricating property than the non-texturing one in some conditions. And the seal with micro pores and macro pumping grooves performed better property in all test conditions.On the other hand, however, the micro-pores texturing type has some shortcomings. It leaked a lot in low-load condition while showed considerable friction in high-load and low rotates speed conditions. The shortcomings didn't occur during the test on seal with micro pores and macro pumping grooves.Detail reasons could be found after analysis:Firstly, the sealing behavior is improved because of the upstream effect. And it is reasonable that the dynamic effect of pores the can help to improve friction behavior. Both of which are belong to the conclusion of theory research. Secondly, besides pumping effect, the grooves of seal with pores and pumping grooves can hold liquid. When the liquid goes into interfaces.The faces were lubricated and the axial vibration was absorbed. Thirdly, friction coefficient of seal with pores may increase under high load and axial vibration conditions because of the cut and crash between pores and asperity peaks.