US3747394A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pipe mandrel for use during bending
Assignee: CRC Evans Pipeline International Inc
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Filing: 1972-03-27
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Granted: 1973-07-24
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Expires: 1992-03-27
Abstract
Abstract A pipe bending mandrel for use inside the pipe embodies a flexible body suspended between spaced supports and made of a series of diametrically opposed, pipe-engaging shoes that are clamped tightly in place against the pipe by toggle joints in a manner to preclude displacement during bending so that pipe buckling and wrinkling at the bend are effectively eliminated. A reciprocable control common to the toggles and actuated by a single power device results in equalized forces imparted to the pipe by all of the shoe assemblies, assures complete lock-in of all of the assemblies prior to bending, and causes all of the assemblies to cooperate in preventing collapse of any one or more of the assemblies while bending takes place. The shoes are stragetically arranged only along those zones where buckling and wrinkling would normally occur, but at those zones the shoes are shaped, sized, spaced and adequate in number such as to accomplish optimum results.
Inventors
- 👤 J Cunningham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 01:44
CPC Classifications
B; B21; B21D; B21D9/00; B21D9/01; B21D9/03
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
202 words
A mandrel adapted for insertion into and use during bending of a pipe comprising: a pair of spaced supports; an elongated, bendable body suspended between the supports and provided with a series of side-by-side shoe assemblies, each assembly including: a pair of diametrically opposed shoes, each provided with an outermost, convex, pipe-engaging surface, and a toggle disposed between and pivotally connected with the shoes thereof, each toggle having an arrangement which includes a pair of opposed couplings connected together in end-to-end relationship, presenting a knee joint, each pair of couplings being normally out of alignment so that when a force is applied in one direction to said joint thereof to straighten the arrangement said shoes will receive endwise thrusts from the couplings radially outwardly in opposite directions to clamp said surfaces of the shoes with substantially equal pressure against the inner face of the pipe throughout the length of the body; and an elongated, flexible, push-pull device at said joints and common thereto, said device pivotally interconnecting the couplings, extending longitudinally of the body and the pipe, spanning the distance between the supports and being reciprocable with respect to the supports axially of the device for actuating all of the couplings simultaneously.
Claim 2
Dependent Claim
202 words
A mandrel adapted for insertion into and use during bending of a pipe comprising: a pair of spaced supports; an elongated, bendable body suspended between the supports and provided with a series of side-by-side shoe assemblies, each assembly including: a pair of diametrically opposed shoes, each provided with an outermost, convex, pipe-engaging surface, and a toggle disposed between and pivotally connected with the shoes thereof, each toggle having an arrangement which includes a pair of opposed couplings connected together in end-to-end relationship, presenting a knee joint, each pair of couplings being normally out of alignment so that when a force is applied in one direction to said joint thereof to straighten the arrangement said shoes will receive endwise thrusts from the couplings radially outwardly in opposite directions to clamp said surfaces of the shoes with substantially equal pressure against the inner face of the pipe throughout the length of the body; and an elongated, flexible, push-pull device at said joints and common thereto, said device pivotally interconnecting the couplings, extending longitudinally of the body and the pipe, spanning the distance between the supports and being reciprocable with respect to the supports axially of the device for actuating all of the couplings simultaneously.
Claim 3
Dependent Claim
26 words
A mandrel as claimed in claim 1, each support being provided with structure pivotally connecting the same with the couplings of the assembly next adjacent thereto.
Claim 4
Dependent Claim
31 words
A mandrel as claimed in claim 1; and a fluid pressure piston and cylinder unit carried by one of said supports and operably connected with said device for reciprocating the latter.
Claim 5
Dependent Claim
25 words
A mandrel as claimed in claim 1, certain of said assemblies having their couplings pivotally connected with the couplings of an assembly next adjacent thereto.
Claim 6
Dependent Claim
30 words
A mandrel as claimed in claim 1, each coupling including a pair of spaced links having plates at opposite ends thereof secured to said device and to corresponding shoes respectively.
Claim 7
Dependent Claim
25 words
A mandrel as claimed in claim 5, each plate being provided with a pair of lugs, each lug being pivotally attached to a corresponding link.
Claim 8
Dependent Claim
27 words
A mandrel as claimed in claim 6, certain of said assemblies having certain of their lugs pivotally connected with corresponding lugs of an assembly next adjacent thereto.
Claim 9
Dependent Claim
28 words
A mandrel as claimed in claim 1, each coupling having a plate pivotally attached thereto, said device including a pair of bars crossing the plates and joined thereto.
Claim 10
Dependent Claim
26 words
A mandrel as claimed in claim 8; and shim means for increasing the diameter of said body in the direction of radial movement of the shoes.
Claim 11
Dependent Claim
24 words
A mandrel as claimed in claim 9; and releasable fasteners clamping the shim means between the plates and clamping the plates between the bars.
Claim 12
Dependent Claim
46 words
A mandrel as claimed in claim 1 wherein each series of said assemblies is coextensive in length with said body and one of said series is circumferentially spaced from the other of said series throughout the length of the body at both ends of all shoes.
Claim 13
Dependent Claim
31 words
A mandrel as claimed in claim 11 wherein each shoe is continuous from end-to-end thereof along its said outermost surface for engagment with substantially one-fourth of the circumference of the pipe.
Claim 14
Dependent Claim
26 words
A mandrel as claimed in claim 12, each support being provided with structure pivotally connecting the same with the couplings of the assembly next adjacent thereto.
Claim 15
Dependent Claim
25 words
A mandrel as claimed in claim 13, certain of said assemblies having their couplings pivotally connected with the couplings of an assembly next adjacent thereto.
Claim 16
Dependent Claim
24 words
A mandrel as claimed in claim 14 wherein a majority of said assemblies are pivotally connected through their couplings in a plurality of pairs.
Claim 17
Dependent Claim
65 words
A mandrel as claimed in claim 15; and a fluid pressure piston and cylinder unit carried by one of said supports for reciprocating said device, the piston of said unit being aligned with said device, reciprocable within the one support and connected at one end thereof with one end of the device, the opposite end of the device being reciprocably carried by the other support.
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) | 1976-07-23 | 1977-01-22 | 1977-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-23 | 1981-01-22 | 1981-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-23 | 1985-01-22 | 1985-07-24 | $7700.00 | Window Closed / Lapsed |