Patent US3749411A successfully refreshed from Google Patents.
US3749411A
Expired / Lapsed
US
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Shaft sealing system
Assignee: NETTCO CORP
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Filing: 1971-07-19
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Granted: 1973-07-31
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Expires: 1991-07-19
Abstract
Abstract A shaft sealing system employs a conventional liquid barrier unit to prevent leakage of gases between the shaft and its support. The system also includes a chamber positioned above the unit and communicating with it. When the unit is filled with barrier liquid, the liquid level in the chamber is at an upper location thereon. However, when the liquid supply in the unit is depleted, the level in the chamber drops appreciably indicating a gas leak in the sealing system.
Inventors
- 👤 J Lennon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:17
CPC Classifications
F; F16; F16J; F16J15/00; F16J15/16; F16J15/40; Y; Y10; Y10S; Y10S277/00; Y10S277/93
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
125 words
In a fluid shaft seal system employing a liquid barrier unit to carry pressurized barrier liquid forming a gastight seal between the shaft and its support, the improvement comprising an indicator positioned above the highest gravitational point of a fluid loop reentrant on said barrier unit and in fluid communication between an elevated portion of said loop and a normally closed valve which vents the indicator when the valve is open, said indicator being thereby positioned to receive barrier fluid from said loop when said valve is opened and to receive gas traveling through said loop from said barrier unit when said valve is closed, said gas displacing fluid from said indicator into said loop to thereby indicate a gas leak in said barrier unit.
Claim 2
Dependent Claim
125 words
In a fluid shaft seal system employing a liquid barrier unit to carry pressurized barrier liquid forming a gastight seal between the shaft and its support, the improvement comprising an indicator positioned above the highest gravitational point of a fluid loop reentrant on said barrier unit and in fluid communication between an elevated portion of said loop and a normally closed valve which vents the indicator when the valve is open, said indicator being thereby positioned to receive barrier fluid from said loop when said valve is opened and to receive gas traveling through said loop from said barrier unit when said valve is closed, said gas displacing fluid from said indicator into said loop to thereby indicate a gas leak in said barrier unit.
Claim 3
Dependent Claim
36 words
The system defined in claim 10 wherein the unit is part of a closed loop including a heat exchanger and a pump so that the barrier liquid can be circulated around the loop for cooling purposes.
Claim 4
Dependent Claim
57 words
The system defined in claim 2 and further including means for connecting the unit to a barrier liquid supply so that additional liquid can be introduced into the unit when the indicating means indicates the existence of a leak and means for venting the system so as to remove any gas from the loop and indicating mEans.
Claim 5
Dependent Claim
47 words
The system defined in claim 3 wherein the connecting and venting means include remotely controlled valves and the indicating means is responsive to said drop of the barrier liquid level so as to automatically control the valves to maintain the proper amount of liquid in the unit.
Claim 6
Dependent Claim
26 words
The assembly defined in claim 10 wherein the indicator includes a sight glass by which the level of liquid in the chamber may be observed directly.
References Cited (Backward Citations)
GB687120A
Cited
US3106099A
Cited
US3115347A
Cited
US3392983A
Cited
US3441048A
Cited
US3489419A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |