← Back to Patent Explorer
US3810491A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of insulating conduit

Assignee: Linde GmbH
•
Filing: 1972-10-26
•
Granted: 1974-05-14
•
Expires: 1992-10-26
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method of insulating conduit of the double-wall type in which an inner pipe is coaxially surrounded by an outer pipe and the intervening space contains insulating materials as well as some means for positioning the two pipes coaxially. The inter-pipe space is evacuated and the inner tube may be employed for conducting low-temperature fluids and/or for receiving a lowtemperature electrical cable, e.g., a superconductor. The insulating material is applied in generally helical bands while spacers are distributed in a helical pattern along the inner pipe and are subsequently removed to permit tension means to be provided between the inner and outer pipes so that the system for relatively positioning the two pipes is not under compression but exclusively under tension.

Inventors

  • 👤 U Hildebrandt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 04:11
CPC Classifications
F; F16; F16L; F16L59/00; F16L59/14; F16L59/16; F16L59/141; Y; Y10; Y10S; Y10S138/00; Y10S138/05; Y10T; Y10T29/00; Y10T29/49; Y10T29/49826; Y10T29/49863; Y10T29/49879

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 81 words
A method of making an insulated conduit comprising the steps of: mounting a plurality of general radial spacer elements at spaced locations along an inner pipe; wrapping said inner pipe with insulating material around said spacer elements and in a plurality of layers to substantially the tops of said elements; removing said elements; and enclosing the insulating-wrapped inner pipe with an outer pipe while suspending said inner pipe within said outer pipe under tension at locations vacated by said spacer elements.
Claim 2
Independent Claim 81 words
A method of making an insulated conduit comprising the steps of: mounting a plurality of general radial spacer elements at spaced locations along an inner pipe; wrapping said inner pipe with insulating material around said spacer elements and in a plurality of layers to substantially the tops of said elements; removing said elements; and enclosing the insulating-wrapped inner pipe with an outer pipe while suspending said inner pipe within said outer pipe under tension at locations vacated by said spacer elements.
Claim 3
Dependent Claim 35 words
The method defined in claim 1 wherein said spacer elements are mounted on said inner pipe by helically wrapping a band containing said elements at spaced locations around the outer wall of said inner pipe.
Claim 4
Dependent Claim 23 words
The method defined in claim 2 wherein said band carrying said spacer elements is composed of metal and said elements are metal tubes.
Claim 5
Dependent Claim 28 words
The method defined in claim 3 wherein said insulating material is wrapped around said inner pipe in a plurality of layers in helical bands wound in opposite directions.
Claim 6
Dependent Claim 44 words
The method defined in claim 4, further comprising applying a retaining band around the insulation on said inner pipe and anchoring said retaining band to the band originally carrying said spacer elements with tension members, said outer pipe being applied over said retaining band.
Claim 7
Dependent Claim 17 words
The method defined in claim 5, further comprising the step of evacuating the space between said pipes.
Claim 8
Dependent Claim 113 words
An insulated conduit assembly comprising: an inner pipe, a metal band wound around the outer wall of said inner pipe generally helically and provided with anchoring formations at equispaced locations along said band; a plurality of layers of thermal insulation formed in oppositely helically wrapped bands surrounding said pipe and having spaced turns whereby the spaces between turns of said layers cross in radial alignment with said formations; a retaining band overlying said insulation and provided with formations at the crossing locations of the insulating bands; respective tension elements interconnecting the formations of said metal band and the formations of said retaining band under tension; and an outerpipe fitted over said retaining band.
Claim 9
Dependent Claim 113 words
An insulated conduit assembly comprising: an inner pipe, a metal band wound around the outer wall of said inner pipe generally helically and provided with anchoring formations at equispaced locations along said band; a plurality of layers of thermal insulation formed in oppositely helically wrapped bands surrounding said pipe and having spaced turns whereby the spaces between turns of said layers cross in radial alignment with said formations; a retaining band overlying said insulation and provided with formations at the crossing locations of the insulating bands; respective tension elements interconnecting the formations of said metal band and the formations of said retaining band under tension; and an outerpipe fitted over said retaining band.
Claim 10
Dependent Claim 44 words
The assembly defined in claim 7 wherein said formations of said metal band are adapted to releasably accommodate tubular spacer pins for maintaining access to said formations upon the wrapping of said insulating bands around said inner pipe, said pins having inwardly tapering extremities.
Claim 11
Dependent Claim 30 words
The assembly defined in claim 8 wherein said bands of insulation each consist of at least one reflective metal-foil layer and a cellular layer bonded to said metal foil layer.
Claim 12
Dependent Claim 13 words
The assembly defined in claim 9 wherein said elements are thin metal wires.

References Cited (Backward Citations)

US3126918A Cited
GB372745A Cited
US2707493A Cited
FR1060740A Cited
DE947583C Cited
US2933917A Cited
US2962051A Cited
US3369826A Cited
US3397720A Cited
US3439885A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-05-13 1977-11-12 1978-05-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-05-13 1981-11-12 1982-05-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-05-13 1985-11-12 1986-05-14 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag