PPC Mechanical Seals
Description: Plan 65A is a liquid leakage detection system measured by a level transmitter, arranged to set off an alarm when EXCESSIVE leakage occurs. Normally for Arrangement 1 single seals. The orifice downstream of the level transmitter is typically 1/4” located in a vertical piping leg. Includes a bypass around the orifice to prevent pressure […]
Description: Plan 62 is an external source supplying quench (nitrogen, water, steam, etc.) on the atmosphere side of the seal. Typically used with a throttle bushing or auxiliary sealing device for containment. Objective: To reduce oxidation, coking or crystallization of process accumulating on the atmospheric side of the seal. Advantages: Utilizes miniscule flow rate of […]
Description: Plan 54 is an external system supplying clean BARRIER fluid to an Arrangement 3 dual seal at greater pressure than the process pressure being sealed. Pressure and circulation are provided for by an external pump or pressure system. Objective: Same as Plan 53A and will provide constant pressure and flow through circulation system. Advantages: […]
Description: Plan 53C utilizes a reference line from the process in the seal chamber as a pressure source to a PISTON ACCUMULATOR. Provides a PRESSURIZED system greater than the process pressure being sealed, providing clean BARRIER fluid to an Arrangement 3 dual seal. Circulation provided by an internal pumping ring. Objective: Same as Plan 53A, […]
Description: Plan 53A is an external reservoir, PRESSURIZED greater than the seal chamber pressure. Provides clean BARRIER fluid to an Arrangement 3 dual seal. Typically pressure is provided by nitrogen gas below 200 psig. Circulation provided by an internal pumping ring. Objective: Provide favorable environment for long seal life. Ensure zero process emissions to environment. […]
Description: Plan 52 is an external reservoir, typically NON‐PRESSURIZED or maintained at a pressure less than the pressure in the seal chamber. Provides BUFFER fluid for the outer seal of an Arrangement 2 dual seal. Circulation provided by an internal pumping ring. Objective: To reduce human and environmental contact in the event of a primary […]
Description: Plan 41 is recirculation from pump discharge through a CYCLONE SEPARATOR, sending clean flush through a seal flush cooler, then into the seal chamber. Heavy particles are sent back to pump suction. Objective: Cool and clean process being sent to the seal chamber, improving lubricity and increasing the vapor margin in the seal chamber. […]
Description: Plan 32 is injection of a cleaner or cooler fluid to the seal chamber from an external source, mixing into the process stream. Objective: Isolate fluid in the seal chamber from process. Using a close‐clearance throat bushing, the injected fluid can isolate the seal from a process with poor lubricity, high temperature, abrasive, dirty, […]
Description: Plan 31 is recirculation from pump discharge through a CYCLONE SEPARATOR, sending clean flush into the seal chamber and heavy particles back to pump suction. Objective: Dissipate seal generated heat and vent the seal chamber at start‐up. Remove solids from the seal flush and seal chamber. Advantages: Raises the pressure in the stuffing box […]
Description: Plan 23 is recirculation of process fluid from the seal chamber, through a seal flush cooler, back into the seal chamber utilizing a pumping ring. Objective: Cool process, improving lubricity and increasing the vapor margin in the seal chamber. Reduce coking. Advantages: Has greater cooling efficiency than Plan 21 because it continuously recirculates the […]