A mechanical seal is a device that helps join systems and mechanisms together by preventing leakage (e.g. in a pumping system), containing pressure, or excluding contamination. The effectiveness of a seal is dependent on adhesion in the case of sealants and compression in the case of gaskets. The seals are installed in pumps in a wide range of industries including chemicals, water supply, paper production, food processing and many other applications.
A stationary seal may also be referred to as 'packing'.
- Induction sealing or cap sealing
- Adhesive, sealant
- Bodok seal, a specialized gas sealing washer for medical applications
- Bonded seal, also known as Dowty seal or Dowty washer. A type of washer with integral gasket, widely used to provide a seal at the entry point of a screw or bolt 
- Bridgman seal, a piston sealing mechanism that creates a high pressure reservoir from a lower pressure source
- Split seals are innovative sealing solutions designed to enhance efficiency and convenience in various mechanical systems. These seals are specifically engineered to address the challenges associated with traditional seals, offering improved installation, maintenance, and operational benefits.
- Compression seal fitting
- Diaphragm seal
- Ferrofluidic seal
- Gasket or Mechanical packing
- Glass-to-metal seal
- Glass-ceramic-to-metal seals
- Heat seal
- Hose coupling, various types of hose couplings
- Hermetic seal
- Hydrostatic seal
- Hydrodynamic seal
- Inflatable seal Seals that inflate and deflate in three basic directions of operation: the axial direction, the radial-in direction, and the radial-out direction. Each of these inflation directions has their own set of performance parameters for measurements such as the height of inflation and the center-line bend radius that the seal can negotiate. Inflatable seals can be used for numerous applications with difficult sealing issues.
- Labyrinth seal A seal which creates a tortuous path for the liquid to flow through
- Lid (container)
- Rotating face mechanical seal
- Face seal
- Radial shaft seal
- Trap (plumbing) (siphon trap)
- Stuffing box (mechanical packing)
- Wiper seal
- Dry gas seal
- ^ "GFS Mechanical Seals". Gallagher Seals. Retrieved 5 August 2021.
- ^ "The Dowty Bonded Seal" (PDF). Retrieved 12 August 2016.
- ^ "Bonded Seals". Retrieved 12 August 2016.
- ^ "Information about Split Seals". Mechanical Seals. Retrieved 2023-06-02.