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Spiral groove liquid film non-contact mechanical seal ( liquid film sealing , also known as the upstream pumping mechanical seal ) and wear , long life, low energy consumption, stable working conditions and adaptability , etc. , you can achieve zero leakage or even zero escape, has been widely used in the petrochemical pumps, compressors and other rotating fluid machinery . Practical applications , it is inevitable there will be seal failure , severe cases can cause heavy casualties . The cause of the failure , the end face excessive temperature rise due to vaporization of the liquid , it may be the end deformation caused by excessive friction and wear , so it is necessary to study the sealed steady state characteristics of the spiral groove liquid film . Using consider the seal face radially tapered theoretical model by means of the finite element program for solving the steady-state correction Reynolds equation to obtain the end surface of the liquid film pressure distribution, the calculation of the opening force , the pumping rate , stable liquid film stiffness coefficient, the coefficient of friction parameters such as steady - state characteristics of the liquid viscosity , film thickness and radial taper sealing steady-state characteristic parameters . Secondly, according to the energy conservation equation , seal face temperature simplified formula , the preparation of the finite element program to solve the seal face temperature rise distribution and taking into account the coupling between viscosity and temperature , the temperature rise of the coupling relationship between the seal faces distribution. Again , according to the theory of shell of torque solving the deformation of the seal face taper . Finally , the viscosity , temperature, strain and pressure distribution of the mutual coupling between the calculation of the overall the coupled pressure distribution , distribution of temperature rise distribution and viscosity , speed and groove depth of the steady-state characteristics . The steady-state analysis shows that the radial seal faces the taper changed the face radial pressure distribution and pressure gradient , the steady-state characteristics have an important impact . The nature of the viscosity of the liquid decreases with increasing temperature , which can effectively reduce the temperature of the seal face , inhibiting the excessive temperature rise of the end surface . Taper deformation of the seal faces showing the type of convergence is conducive to increased hydrodynamic effect . The end face of the rise of the most significant changes in the overall coupling calculation .
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