Theoretical Study Of Metal Bellows Mechanical Seal With Grading Ring And Optimal Design Of Groove Shape

The mechanical seal(or seal)is the indispensable parts of chemical machinery and power machinery,which plays an important role in the normal operation of the equipment,especially for the chemical equipment which works under the strong corrosive and combustible conditions.At the start-stationary-stop time of the machine,the dynamic and static rings can not be switched quickly from the contact state to the non contact state.If a long time in the sealing contact condition,will cause the sealing between the pump fluid can not be quickly lead to the dynamic and static ring a long time in the state of dry friction,extremely easy to cause the seal wear dry,thus affecting the normal operation of the whole equipment.Therefore,according to the mechanical seal in the start-stop-smooth shape,uniform dynamic and static ring can not be separated quickly,based on the grading ring sealing is to study,on the ring of multil field coupling simulation,comparison of different groove parameters were optimized design.Firstly,this paper establishes the three-dimensional model of the mechanical seal of the bellows,the static analysis results of A type B type corrugated pipe,corrugated pipe and inertia moment of film thickness of the optimization design,parameter selection of good for the next step of calculation.Secondly,on the side of the sealing friction dynamic simulation,calculation of grading ring face pressure rise is relatively flat,volatility is smaller,that the equalizing ring has a buffering effect;modeling of end face shape ring using two-dimensional software of dynamic ring fluid in the whole simulation by FLUENT software,through set different turbulence intensity and hydraulic diameter distribution trend chart back pressure,velocity and flow field of the tank,thereby indirectly calculate the transient end groove opening force.TThe results show that the acceleration of transient opening force changes with the increase of turbulence intensity.Finally,calculation of fluid in tank by using the RNG k-e model of turbulent kinetic energy and dissipation rate,the groove tip dissipation rate,turbulent kinetic energy is maximum in uniform ring diameter region,rapid pressurization effect verification notch tip and balance equalizing ring equalizing effect,provide the basis for future research.