Patent · US Expired

Dual seal with clean barrier fluid and dynamic pressure control

US5769427A · kind A · utility

28Cited by
1References
28Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 8, 1996
Grant dateJun 23, 1998
Priority date
Expiry dateOct 8, 2016

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16J15/3448
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A seal arrangement for a stuffing box, the stuffing box having an outboard seal an inboard seal exposed to process fluid, and a volume pressurized with barrier fluid in which the inboard seal and the outboard seal are disposed, has a container divided into at least two non-communicating chambers by a movable wall, with a first of the chambers being supplied with barrier fluid and communicating with the space in the stuffing box in which the outboard seal is disposed, and a second of the chambers communicating with the stuffing box so as to be at the stuffing box pressure. The movable wall constantly strives to assume an equilibrium position wherein substantially no pressure differential exists across the inboard seal. Due to the absence of such a pressure differential, substantially no contamination of the barrier fluid by the process fluid occurs, and vice versa. Additionally, due to the extremely small amount of clean barrier fluid which is lost during continued operation, barrier fluid replenishment is highly simplified and maintenance-free. The container may also house a barrier fluid reservoir.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.