The static pressure kettle dissolution mechanism and influencing factors were described . In detail elaborated the mechanisms of five procedares of static method dissolving,hydration,first dissolution, hydrolysis, secondary dissolution, ionization.It was pointed out the influnces of a few main factors modulus, temperature and pressure, water ratio and the solid partical on the dissolution of sodium silicate were discussed, and the problems in the melting process were solved optimization, operations of the static dissolving sodium silicate process were improved.