Mechanical Seal Performance Requirements

The performance requirements of mechanical seals include the following aspects:

Working parameters

Working pressure: 0-1.5691MPa (referring to the actual pressure in the sealing chamber)

Working temperature: -20℃-80℃ (referring to the actual temperature in the sealing chamber)

Shaft (or sleeve) outer diameter: 10-120mm

Speed: not more than 3000r/min

Technical requirements for parts

Flatness and roughness of the sealing end face:

Flatness deviation is not more than 0.0009mm

The maximum allowable value of the roughness R of the sealing end face of metal materials is 0.2μm

The maximum allowable value of the roughness R of the end face of non-metallic materials is 0.4μm

Installation technical requirements

Radial runout tolerance of the shaft (or sleeve): <0.04mm

Outer diameter size tolerance: h6

Surface roughness: Ra is not more than 3.2u m

‌Axial runout of the rotor‌: <0.1mm

‌Runout tolerance of the positioning end face of the sealing chamber and the sealing end cover on the shaft (or sleeve) surface‌: <0.04mm

‌Surface roughness of the contact part with the auxiliary sealing ring‌: Ra<3.2um

Performance parameters

‌Shaft diameter‌: Generally ranges from 6-200mm, and can reach 400mm in special cases

‌Speed‌: Generally the same as the pump speed, centrifugal pumps are generally less than or equal to 3000r/min, high-speed centrifugal pumps are less than or equal to 8000r/min, and special pumps are less than or equal to 4000r/min

‌Average circumferential speed of the sealing surface‌: Generally less than or equal to 30m/s, and can reach less than or equal to 150m/s in special cases

‌‌End face specific pressure‌: Generally 0.3-0.6MPa for internal mechanical seals and 0.15-0.4MPa for external mechanical seals