China Sealcon Company

Stationary Seats

A mechanical seal is a device that helps join systems or mechanisms together by preventing leakage.

Rotary and stationary rings are the main components of a mechanical seal.
Stationary Seats (Mating Rings) are the non-rotating primary seal ring mounted
in the gland plate or other motionless structural parts of the rotating equipment.


The mechanical seal stationary or mechanical seal seat is made of stationary ring /mating ring and Secondary sealing components, such as PTFE, Viton, NBR etc.

The static seal ring (also known as the stationary ring)  work with the rotary sealing surface to prevent media leakage.

Stationary Seats Material combination:

Pump mechanical seal work at high-speed rotation, withstand a certain pressure to prevent the media corrosion, temperature changes. Therefore, the requirements of the material in the following areas: 
1. with the high modulus of elasticity, lower strength and coefficient of linear thermal expansion coefficient, excellent wear resistance and self-lubrication and good impermeability. 
2. prevent damage from medium corrosion, abrasion, dissolution, and swelling caused. 
3. good thermal conductivity, heat resistance, cold resistance and temperature mutation adaptability.

Stationary face:

tungsten carbide, silicon carbide, ceramic, carbon etc.
Secondary sealing components:
NBR, EPDM, VITON, Aflas, FEP, FFKM etc.

Stationary Seat Classification:

Mechanical seal seat has many different shapes, Generally can be divided into 2 groups:

1. Boot Mounted/Cut mounted stationary 
For example,
  • Bergmann mechanical seal G60, G24, G50, G55 seat,
  • john crane mechanical seal M, N stationary.

2. O-ring mounted Stationary
For example:
  • Burgmann Mechanical Seals G6,G606,G4,G13 ,G9 ,G16 ,G46 ,G9,G9A seat,
  • John Crane Mechanical Seals BO,BS,BP,BD,PG,A,V,W,WG Stationary Seat ,
  • Vulcan 12DIN seat etc.

Difference between Rotary and stationary:

  • The Rotary ring rotates with the rotation of the main shaft, and the stationary ring is a sealing ring which is fixed on the mechanical seal sleeve and does not rotate with the shaft.
  • The end of the spring is usually a rotary ring. But There are some exceptions. For high temperature and high-speed conditions, some seal products are designed to rotate in a stationary ring. The moving ring is stationary. The moving ring only moves axially under the force of the spring.
  • Mechanical seal sealing surface usually has a wider face and a narrower face .the one with the narrow face is usually the rotary ring, the one with the wider face is the stationary ring.

Stationary Seats Installation notice:

  • Before installation, it is necessary to check whether the sealing parts are enough and whether the components are damaged or not. Especially, there are no defects such as bumps, cracks, and deformation on the moving and static rings. If there is a problem, repair or replacement of new spare parts is required.
  • the gland should be corrected after the coupling. The bolt should be tightened evenly, to prevent the gland section deflection, with the feeler or special tools to check the points, the error should be not greater than 0.05 mm.
  • The rotary ring should maintain flexible mobility, the rotary ring should be able to automatically spring back after the pressure to the spring.
  • the installation process must not be allowed to use the tool directly tap the sealing element, you must use special tools to beat to prevent the sealing element damage.
  • mechanical seal components and their assembly contact surface must be cleaned with acetone or anhydrous alcohol before installation. During the installation process should be kept clean, especially rotary, stationary ring and auxiliary sealing elements should be free of impurities, dust. Dynamic and static ring surface should be coated with a layer of clean oil or turbine oil.
  • TEL:+86-571-86959751
  • FAX:+86-571-86959791
  • EMAIL:sales@china-sealcon.com
  • ADDRESS:A1-3-603 Xixi center, Wenyi west road, Xihu district, 310012, Hangzhou, China