US3661670A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming fiber glass pipe with integral joint thread
Assignee: Smith Fiberglass Products Inc
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Filing: 1969-09-15
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Granted: 1972-05-09
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Expires: 1989-09-15
Abstract
Abstract Glass reinforced plastic pipe having preformed threads integrally disposed therein formed by: (1) molding threaded portions wherein the outer surface is preferably corrugated or irregular and which tapers down to the inside diameter of the pipe to which the thread is to be attached; (2) mounting said molded thread on the end of a mandrel; and (3) forming a pipe on said mandrel by providing pretensioned filamentous reinforcements longitudinally and helically disposed thereon and imbedded in a cured resin. The described tapered portion and corrugated portion of the thread is overwound with the above-mentioned helical and longitudinal filamentous material.
Inventors
- 👤 William H Pierpont Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:43
CPC Classifications
B; B29; B29D; B29D23/00; B29D23/001; B29C; B29C53/00; B29C53/56; B29C53/58; B29C53/583; B29C53/585; B29C53/80; B29C53/8008; B29C53/805; B29C70/00; B29C70/68; B29C70/86; B29D1/00; B29D1/005; F; F16; F16L; F16L47/00; F16L47/16; F16L9/00; F16L9/16; B29K; B29K2309/00; B29K2309/08
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
151 words
A method for forming a glass reinforced resin pipe having a first threaded end poRtion which comprises: a. premolding a threaded end portion, the outer surface of which tapers inwardly in a rearward direction toward the center axis of the pipe to be formed; b. applying a plurality of layers of glass roving imbedded in a resin to a rotatable mandrel to form partially a pipe; c. placing the premolded threaded end portion adjacent to the end of the wall of the premolded pipe, the premolded portion and partially formed pipe having a common center line; d. applying concurrently the roving to the mandrel and the premolded portion, i. completing the formation of the pipe while ii. bonding integrally to the pipe by applying said roving to the premolded threaded end portion; e. curing said resin; and f. removing the thus formed pipe with the threaded end portion from the mandrel.
Claim 2
Dependent Claim
19 words
The method of claim 1 which includes applying said layers as alternate layers of longitudinal and helical glass roving.
Claim 3
Dependent Claim
25 words
The method as defined in claim 1 wherein said premolded threaded end portion carries irregularities in at least a portion of the outer wall thereof.
Claim 4
Dependent Claim
28 words
The method as defined in claim 1 wherein said premolded threaded end portion contains a tapered portion in the outer wall adjacent to the body of said pipe.
Claim 5
Dependent Claim
21 words
The method as defined in claim 2 which includes applying said layers as alternate layers of longitudinal and helical glass roving.
Claim 6
Dependent Claim
25 words
The method as defined in claim 2 wherein said premolded threaded end portion carries irregularities in at least a portion of the outer wall thereof.
Claim 7
Dependent Claim
28 words
The method as defined in claim 2 wherein said premolded threaded end portion contains a tapered portion in the outer wall adjacent to the body of said pipe.
References Cited (Backward Citations)
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US3381716A
Cited
US3293860A
Cited
US3412891A
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US3462175A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-09 | 1975-11-08 | 1976-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-09 | 1979-11-08 | 1980-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-09 | 1983-11-08 | 1984-05-09 | $7700.00 | Window Closed / Lapsed |