US3789181A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of spirally winding strip metal about a pipe, and securing adjacent strips by welding
Assignee: SA SWEMAT NV CENTRE COMMERICAL DES DAUPHINS 26 AVENUE DES QUATRE SAISONS B-1410 WATERLOO BELGIUM
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Filing: 1972-08-10
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Granted: 1974-01-29
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Expires: 1992-08-10
Abstract
Abstract An annular carrier cage is placed around the pipe, which may be insulated. The carrier cage supports a holder for stainless steel strip, a flange forming apparatus, a flange extension apparatus, seam welding apparatus and a post-welding, flange stress relieving apparatus. To permit curling of the flanged strip about the circumference of the pipe, the flange extension apparatus reduces the diameter of the formed flange adjacent the edge thereof, for example by exerting pressure against the flange strip by a pair of conical rollers having their greater diameter adjacent the free edge of the flange. Adjacent flanges are welded together by roller electrodes, and a pair of conical rollers similar to the flange extension apparatus then bear against the welded joints to relieve stresses due to welding and provide for a tight wrap of the spiral, welded strip about the pipe.
Inventors
- 👤 S Netterstedt
- 👤 B Lindstrand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:07
CPC Classifications
B; B21; B21C; B21C37/00; B21C37/06; B21C37/12; B23; B23K; B23K11/00; B23K11/08; B23K11/082; B23K11/084
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
151 words
Method of spirally wrapping a strip of metal, having lateral edges, around a pipe and interconnecting adjacent strips comprising continuously uncoiling a flat strip of metal from a roll and orienting the strip over the pipe to form a sprial; forming a flange projecing away from the pipe at both lateral edges of the metal strip as it is being uncoiled; reducing the thickness of the flanges adjacent the edges of the flanges to permit curling of the flanges about their edges and, hence, wrapping of the strip about the pipe with the flanges projecting radially therefrom; spirally wrapping the flanged strip about the pipe; continuously pressing together adjacent projecting flanges of the uncoiling strip, and the turn previously wound about the pipe, as the coil unwinds; and continuously welding said pressed together adjacent flanges of the uncoiling strip, and the turn previously wound about the pipe along their adjacent surfaces.
Claim 2
Dependent Claim
151 words
Method of spirally wrapping a strip of metal, having lateral edges, around a pipe and interconnecting adjacent strips comprising continuously uncoiling a flat strip of metal from a roll and orienting the strip over the pipe to form a sprial; forming a flange projecing away from the pipe at both lateral edges of the metal strip as it is being uncoiled; reducing the thickness of the flanges adjacent the edges of the flanges to permit curling of the flanges about their edges and, hence, wrapping of the strip about the pipe with the flanges projecting radially therefrom; spirally wrapping the flanged strip about the pipe; continuously pressing together adjacent projecting flanges of the uncoiling strip, and the turn previously wound about the pipe, as the coil unwinds; and continuously welding said pressed together adjacent flanges of the uncoiling strip, and the turn previously wound about the pipe along their adjacent surfaces.
Claim 3
Dependent Claim
20 words
Method according to claim 1, including the step of cold working adjacent welded flanges to relieve stresses due to welding.
Claim 4
Dependent Claim
47 words
Method according to claim 2, including the step of rolling adjacent welded flanges between rollers exerting greater compressive forces adjacent the edges of the flanges than adjacent the junction of the flanges with the strip, to relieve stresses due to welding and to additionally curl the flanges.
Claim 5
Dependent Claim
66 words
Method according to claim 1, wherein the step of reducing the thickness of the flanges adjacent the edges of the flanges to permit curling of the flanges about its edges comprises rolling said flanges between a pair of rollers which exert greater compressive force against the flanges adjacent its edges than adjacent the region where the flanges are joined to the major plane of the strip.
Claim 6
Dependent Claim
87 words
Method according to claim 1, wherein the step of spirally wrapping the flanged strip comprises uncoiling said strip from a carrier by uncoiling the coil about an axis inclined with respect to the axis of the pipe being wrapped; and moving the coil about the circumference of the pipe, as well as moved longitudinally thereof, the angle of inclination being selected, with respect to the width of the strip less the hiehgt of the flanges, to obtain closely adjacent turns with the flanges located adjacent each other.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |