Shaft Seal Forms of Mud Pumps
The mud pump can adopt two types of shaft seals: a twin-seal consisted of auxiliary impeller sealing combined with packing sealing, and a mechanical seal.
(1) Auxiliary Impeller Sealing of mud pump: The salve blade seal utilizes the pressure seal generated by the impeller and the auxiliary impeller connected in series, and the packing or lip sealing ring serves as a parking seal. When the positive pressure value at the pump inlet is not greater than 10% of the outlet pressure value of single-stage pumps or fist stage pump of multi-stage pumps connected in series, this seal form is adopted. It can run without shaft sealing water, without diluting the slurry, and has good sealing performance. But it will increase power consumption (generally requiring an increase of about 5% on shaft power)
(2) Packing sealof mud pump: which is a common form of shaft seal, suitable for kinds of working conditions, and can be made of special materials such as PTFE polytetrafluoroethylene and graphite, which can be used in corrosive or high-temperature medium. It has simple structure and is convenient to do maintenance.
(3) Mechanical seal of mud pump: This uses leading sealing technology, the sealing performance is good. The Cartridge Mechanical Sea structure makes installation and replacement convenient, and different structural forms adapt to different working conditions. The friction pairs are made of high hardness ceramics and alloy. The mechanical seal and sealing box are designed and matched in accordance with the flow state of the medium, so they have high wear resistance and seismic resistance, ensuring smooth working in various harsh conditions.
