Selection of Mechanical Seal of Fluoroplastic Centrifugal Pump

In IHF, FSB, GD centrifugal pumps, mechanical seals are easily damaged parts in assembly parts. Why is the motor speed selected at 1450r/min instead of 2900r/min in the selection of large diameter centrifugal pumps because of the wear caused by linear speed . We chooses the WB2 external singleend face grinding seal, which has a simple structure and is easy to watch. Main materials: silicon nitride against grinding silicon nitride; silicon carbide against grinding silicon carbide; ceramic against grinding ceramics; pressureless sintering against grinding and pressureless sintering. Different materials are suitable for different working conditions.

Hydrofluoric acid medium:

React with silicon carbide: SiC+4HF=SiF4+CH4

React with silicon nitride: Si3N4+12HF═3SiF4+4NH3↑

React with silicon dioxide in ceramics: SiO2+4HF=2H2O+SiF4

Sodium hydroxide medium (caustic soda):

React with silicon carbide, reaction equation: SiC+2NaOH+H2O==Na2SiO3+C+2H2

The main components of ceramics are SiO2, 2NaOH + SiO2 = Na2SiO3+H2O

Hydrochloric acid medium: When selecting mechanical seals, it is necessary to choose a relatively strong grinding material, such as: silicon carbide, pressureless sintering;