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US4114657A Expired / Lapsed US ⏱️ 0.0 years remaining

Large-diameter insulated pipe

Assignee: Pont a Mousson SA
•
Filing: 1977-09-27
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Granted: 1978-09-19
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Expires: 1997-09-27
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Abstract

Abstract The insulated pipe comprises an inner pipe and a foam of thermally insulating plastics material which adheres to the inner pipe and to an outer protective layer. The foam material covers the major part of the inner pipe but terminates at a distance from each end thereof in a portion having an inclined surface of frustoconical shape. The outer protective layer comprises a cover which is relatively rigid and terminates before reaching each frustoconical surface and a protective case for each frustoconical surface of the foam material. The case is at one end fixed to the cover and at the other end integral with the inner pipe. The case has sufficient elasticity to allow the foam to follow the expansion of the inner pipe while the cover remains immobilized.

Inventors

  • 👤 Michel Langenfeld

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 23:48
CPC Classifications
F; F16; F16L; F16L59/00; F16L59/14; F16L59/16; F16L59/18; F16L59/182; F16L59/143

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 154 words
A large-diameter insulated pipe for conveying fluids at high temperature comprising an inner pipe, an outer protective layer, a foam of thermally insulating plastics material which is interposed between the inner pipe and outer layer and adheres to the inner pipe and to the outer layer and which covers a major part of the inner pipe but terminates at a distance from each of the ends of the inner pipe in a portion having an inclined surface of substantially frustoconical shape, said outer layer comprising a cover which is relatively rigid and terminates before reaching each frustoconical surface and a protective case for each of the frustoconical surfaces of the foam which case is at one end fixed to the cover and at the other end directly integral with the inner pipe, said case having sufficient elasticity to allow the foam to follow the expansion of the inner pipe while the cover remains immobilized.
Claim 2
Dependent Claim 154 words
A large-diameter insulated pipe for conveying fluids at high temperature comprising an inner pipe, an outer protective layer, a foam of thermally insulating plastics material which is interposed between the inner pipe and outer layer and adheres to the inner pipe and to the outer layer and which covers a major part of the inner pipe but terminates at a distance from each of the ends of the inner pipe in a portion having an inclined surface of substantially frustoconical shape, said outer layer comprising a cover which is relatively rigid and terminates before reaching each frustoconical surface and a protective case for each of the frustoconical surfaces of the foam which case is at one end fixed to the cover and at the other end directly integral with the inner pipe, said case having sufficient elasticity to allow the foam to follow the expansion of the inner pipe while the cover remains immobilized.
Claim 3
Dependent Claim 36 words
A pipe as claimed in claim 1, wherein the foam has a density which is higher at the interfaces between the foam and the inner pipe and the cover than within the mass of the foam.
Claim 4
Dependent Claim 20 words
A pipe as claimed in claim 1, comprising a fixing collar which renders the case integral with the inner pipe.
Claim 5
Dependent Claim 44 words
A pipe as claimed in claim 1, comprising a male end constituted by a smooth end portion and a coating of a heat-resistant plastics material which covers the male end and is capable of having a sealed and sliding contact with a sealing element.
Claim 6
Dependent Claim 32 words
A pipe as claimed in claim 1, comprising a female end portion defining a cavity which is for housing a sealing element, a coating of a heat-resistant plastics material covering said cavity.
Claim 7
Dependent Claim 25 words
A pipe as claimed in claim 1, wherein the protective case for the ends of the insulating foam is constituted by a sheet of rubber.
Claim 8
Dependent Claim 24 words
A pipe as claimed in claim 1, wherein the insulating foam material is a material which has been cold sprayed onto the inner pipe.
Claim 9
Dependent Claim 25 words
A pipe as claimed in claim 7, wherein said foam material is polyurethane and has a density of the order of 80 to 120 kg/cu.meter.
Claim 10
Dependent Claim 17 words
A pipe as claimed in claim 1, wherein the cover is helically wound around the foam material.
Claim 11
Dependent Claim 21 words
A pipe as claimed in claim 1, wherein the cover comprises projections on the outer surface thereof for anchoring the cover.
Claim 12
Dependent Claim 39 words
A pipe as claimed in claim 10, wherein the anchoring projections of the cover are formed by gravel embedded in the outer surface of the cover which ensure that the cover is immobilized axially with respect to the ground.
Claim 13
Dependent Claim 23 words
A pipe as claimed in claim 1, wherein the outer cover is formed by a band of bitumen provided with a non-woven reinforcement.
Claim 14
Dependent Claim 23 words
A pipe as claimed in claim 1, wherein the outer cover is formed by a band of a mixture of bitumen and elastomer.
Claim 15
Dependent Claim 39 words
A pipe as claimed in claim 5, wherein the cavity for housing the sealing element comprises a bored inner end the diameter of which bored end is capable of ensuring a maximum compression of the sealing element of 25%.
Claim 16
Dependent Claim 35 words
A pipe as claimed in claim 5, wherein the female end portion of the pipe comprises an entrance abutment the diameter of which abutment is a function of the desired compression of the sealing element.
Claim 17
Dependent Claim 18 words
A pipe as claimed in claim 1, wherein the cover is constituted by a layer of non-cellular polyurethane.
Claim 18
Dependent Claim 23 words
A pipe as claimed in claim 16, wherein the cover is disposed around the layer of foam by a spraying of the cover.
Claim 19
Dependent Claim 20 words
A pipe as claimed in claim 1, wherein the cover extends and overlaps an adjacent end portion of each case.

References Cited (Backward Citations)

US3508768A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-09-18 1982-03-20 1982-09-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-09-18 1986-03-20 1986-09-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-09-18 1990-03-20 1990-09-19 $7700.00 Window Closed / Lapsed

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