US4389461A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pipeline pig
Assignee: Shell USA Inc
•
Filing: 1982-03-08
•
Granted: 1983-06-21
•
Expires: 2002-03-08
Abstract
Abstract A polymeric foam pipeline pig, having its cells filled with a gel, is resistant to compression when subjected to pipeline pressure.
Inventors
- 👤 Paul R. Scott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:59
CPC Classifications
B; B08; B08B; B08B9/00; B08B9/02; B08B9/027; B08B9/04; B08B9/053; B08B9/055; B08B9/0553; B05; B05D; B05D7/00; B05D7/22; Y; Y10; Y10T; Y10T428/00; Y10T428/8305
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
17 words
A pipeline pig comprising a cylindrically shaped body of polymeric foam having cells filled with a gel.
Claim 2
Dependent Claim
17 words
A pipeline pig comprising a cylindrically shaped body of polymeric foam having cells filled with a gel.
Claim 3
Dependent Claim
15 words
The pig of claim 1 wherein the gel has high viscosity and high yield strength.
Claim 4
Dependent Claim
16 words
The pig of claim 2 wherein the gel is produced from a modified natural polysaccharide polymer.
Claim 5
Dependent Claim
20 words
The pig of claim 1 wherein the pig has a cone shaped nose section integral with the cylindrically shaped body.
Claim 6
Dependent Claim
19 words
The pig of claim 1 wherein the pig has a concave rear section integral with the cylindrically shaped body.
Claim 7
Dependent Claim
16 words
The pig of claim 1 wherein the rear section is coated with a relatively stiff material.
Claim 8
Dependent Claim
26 words
A process for making a pipeline pig comprising, preparing a cylindrically shaped body of polymeric foam and impregnating the cells of the foam with a gel.
Claim 9
Dependent Claim
26 words
A process for making a pipeline pig comprising, preparing a cylindrically shaped body of polymeric foam and impregnating the cells of the foam with a gel.
Claim 10
Dependent Claim
29 words
The process of claim 7 wherein the gel is formed by injecting dry polymeric powder into the foam and then saturating the pig with liquid to form the gel.
Claim 11
Dependent Claim
17 words
The process of claim 8 wherein holes are formed in the pig to facilitate injecting the polymer.
Claim 12
Dependent Claim
29 words
The process of claim 8 wherein the pig is subjected to a vacuum to remove gas from the cells of the foam and facilitate filling the cells with liquid.
References Cited (Backward Citations)
US4216026A
Cited
US4252465A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-06-20 | 1986-12-20 | 1987-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-06-20 | 1990-12-20 | 1991-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-06-20 | 1994-12-20 | 1995-06-21 | $7700.00 | Window Closed / Lapsed |