A mechanical seal controls leakage where a rotating shaft passes through a stationary casing. Its faces, secondary seals, springs and metal parts must work as a system under the actual pressure, temperature, speed and fluid properties.
Define the fluid conditions
Record vapour pressure, solids, crystallisation, lubricity, toxicity and temperature at the seal chamber. Conditions there may differ from the pump suction or discharge. Transients during startup, cleaning and standby can be more demanding than steady operation.
Choose faces and arrangement
Face materials balance wear, heat transfer, chemical resistance and dry-running tolerance. A single seal may suit clean non-hazardous service. Dual arrangements can isolate the process or control emissions but require a correctly designed buffer or barrier system.
Support reliable operation
Check chamber geometry, flush plan, venting, shaft runout and bearing condition. Installation cleanliness matters because small face damage or contamination can create a persistent leak. Keep the specified setting dimensions and test procedure with the equipment record.
