US1769350A - Device for expanding collapsed casings - Google Patents

Description

7 "ff-" 1930. c. LANGSTAFF DEVICE FOR EXPANDING -COLLAPSED CASINGS Filed Aug. 15, 1928 Patented July 1, 1930 mnrsn "STATE-s;

PATENT QFFICE crmro'na. LANGSTAFE, or HAWTHORNE, oamronmn, ASSIGNQR or oxen-minim To FRED A. rommn Ann ONE-THIRD. T0 wr LrAM e. WHALEX, BOTH or: nos AN- GELES, CALIFORNIA;

DEVICE .ron EXPANDING. ooLLArsnn oAsINes.

Application filed August 15, 1928. Serial No. 299,692;

This inventionrelates to an expander tool for expanding casing in a deep well which has collapsed due to a' high externalpr'essure. The general object of the invention is to provide a device of simple construction. for effecting this operation.

A further object of the invention is to provide a device of this kind which will operate in such a way that the rotary move ment of the. tool string carrying the expander tool will operate to effect the expanding of the casing.

Further objects of the invention will appear hereinafter.

The invention consists in the novel parts P and combinations of parts tobe described hereinafter, all of which contribute to produce an eflicient device for expanding col lapsed casing. y

A preferred embodiment of the invention is described in the following specification, while the broad scope of the invention is pointed out inthe appended claims.

In the drawings:

Figure 1 is a side elevation of the expanding device embodying my invention, and showing a short portion of a collapsed casing in cross-section to indicate how the device operates in practice.

Figure 2 is a vertical section through the expander device shown in Figure 1, and in dicating the expander tools or arms in their collapsed or folded condition in full lines, and illustrating the expander tools or arms in dotted lines in their expanded condition.

Figure 3: is a cross-section taken through the device on the line 3'3 of Figure 2.

' Figure 4- is a cross-section on the line 44; of Figure 2.

Figure 5 is a cross-section on the line 5--5 of; Figure 2.

The device includes in its construction a head 1 which isprovided with means, such as a tapered pin 2", for attaching the same at the lower end of the tool string. Below the head I provide a swivel collar 3 to which is attached a plurality of movable expander tools or dogs- 4. These dogs are attached in any suitable manner to enable them to move outwardly in a substantially radial plane. In the present instance, each dog is in'the form of an arm, preferablyar-ranged in pairs and mounted te exten-dl longitudinally with the longitudinal axis of the head 1 and each dog is'attached at its upper end to the under side of the collar by a pivot pin 5. In order to attach these dogs 4, the under side of the collar 3 is provided with a slot 6 corresponding toeach dog, and the dog is formed with atongue 7 that projects up into this slot so that the attaching pins 5 can be driven through the wall ofthe collar in a horizontal plane, being received in drilled openings 8- forthis purose.

In the operation of the tool, the dogs 4 engage the inner wall of a collapsed, casing, such as the casing 9 illustrated in Figure. 1. When the dogs engage the wall of the casing, the casing operates to hold the dogs and the collar 3 against rotation; The tool is constructed so that when this occurs, the

- continued rotation of the head 1 onits longitudinal axis will cause the dogs 4 to-mQve outwardly in succession and expand the collapsed part IO of the casing,

in order to accomplish this, I prefer to provide the lower ends of the dogs; with tapered noses 11 respectively, thatis to say,

each'dog presents an inclined face- 12,, which Ian 3- in place, at the same time permitting it:

to swivel freelyon thelongitudinal'faxils'iof the head. i

The lower portion of the mandrel. provided with cain means for engaging the inner sides of? the expander tools; 4; to expand them. This cam means is preferably the form of two sets of cams, located in different planes of rotation, and includingan upper set consisting of two oppositely-disposed cams 17 (see Figure 4:), and a lower set consisting of two oppositely-disposed cams 18 (see Figure 5). The dogs a are operated in opposite pairs by these cams. The cams 17 will not operate the dogs l (see Figure 4:), but will actuate the dogs 49. This mode of operation is accomplished by providing the dogs 45 with a clearance slot 19 on their inner faces, and by also providing the dogs 4: with a clearance slot 20 on their inner faces. With this construction it will be evident'that when the cams 17 strike the inner faces 21 of the dogs 4: they will force the same outwardly. Likewise, when the cams l8 engage the inner faces of the dogs P these dogs will be moved outwardly.

It will be evident that in the operation of the tool there is'a position of rest, as illustrated in Figures 4 and 5, in which none of the dogs are in their expanded position. This is the position in which the device is lowered down into the casing 9 which is to be expanded. It will be evident that when the noses 11 of the dogs strike the collapsed portion 10 of the casing, they will be held against rotation. By rotating the tool string carrying the head 1, the dogs will be swung outwardly in unison, thereby expanding the casing. As this occurs the tool is gradually lowered.

If the dogs happen to slip around on the inside of the casing, this simply assists in the manipulation of the inner face of the wall, which will eventually expand the collapsed zone 10 back to its normal or proper diameter.

The pins 5 are constructed so that some of the pins overlap the others so as to hold them in place, the last pin driven into place operating as a general key to hold all of the other pins against dislodgment in use. The head and mandrel, and the inner faces of the dogs, are provided with a water bore 22 for carrying circulating water down through the tool if desired. 7

Although I have described this invention as applied to an expander for collapsed casing, it is obvious that the expanding feature of the device may be employed in other tools for example, under-reamers and back-off tools.

It is understood that the embodiment of the invention described herein is only one of the many embodiments this invention may take, and I do not wish to be limited in the practice of the invention, nor in the claims,

to the particular embodiment set forth.

What I claim is:

V 1. In an expanding device for expanding a collapsed casing in a well, the combination of a head having means for attaching the same to the lower end of a tool string, a

collar having a swivel connection on the longitudinal axis of said head, a plurality of expander dogs attached to the collar toward one end so as to swing out at their other ends in a substantially radial direction, and having tapered noses for engaging the wall of the casing at the collapsed point, and means carried by the head for moving the expanding dogs outwardly to expand the collapsed casing.

2. In an expanding device for expanding a collapsed casing in a well, the combination of a head having means for attaching the same to the lower end of a tool string, a collar having a swivel connection on the longitudinal axis of saidhead, a plurality of expander dogs attached to the collar to ward one end so as to swing outwardly at their other ends, and in substantially radial planes to engage the wall of the collapsed casing, and operating so that the engagement with the wall of the casing holds the expander dogs and the collar against rotation on the axis of the head, and means carried by the head and operating by the rotary movement of the head relative to the collar to move theexpander dogs outwardly to expand the collapsed casing;

3. In an expanding device for expanding a collapsed casing in a well, the combination of a head having means for attaching the same to the lower end of a tool string, a collar having a swivel connection on the longitudinal axis of said head, a plurality of expander dogs pivotally attached to the collar adjacent their upper end-sand capable of swinging outwardly in substantially radial planes, said expander dogs having tapered noses for engaging the Wall of the easing at the collapsed point and operating to hold the expander dogs and the collar against rotation, and a mandrel attached to the head extending down on the axis of the head with cam means for engaging the said expander tools when a relative rotary movemtizpt of thehead occurs with regard-s to the co ar.

4:. In an expanding device for expanding a collapsed casing in a well, the combination of a head having means for attaching the same to the lower end of a tool string, a collar having a swivel. connection on the longitudinal axis of said head, a plurality of expander dogs pivotally attached to the collar adjacent their upper ends and capable of swinging outwardly in substantially radial planes with respect to the longitudinal axis of the head, a mandrel attached to the head and extending downwardly from the same on the axis of the head, said expander dogs having tapered noses at their lower ends for engaging the wall of the casing at the collapsed point to hold the expander dogs and the collar against rotation, said mandrel having cams for engaging the inner sides of the expander tools to move the same outwardly when the said head is rotated on its axis relatively to the collar and expander dogs.

5. In an expanding device for expanding a collapsed casing in a well the combination of a head having means for attaching the same to the lower end of a tool spring, a collar having a swivel connection on the longitudinal axis of said head, a plurality i of dogs disposed in oppositely-located pairs,

' pivotally attached at their upper ends to the day of July under side of the collar, a mandrel attached to the under side of the head and extending downwardly on the axis of the head, said mandrel having a pair of oppositely-disposed cams for expanding a pair of oppositely-disposed dogs, and having another pair of oppositely-disposed cams for expanding another pair of oppositely-disposed dog-s, said last-named cams being located in a different plane of rotation from the first-' named cams.

6. In an expanding device for expanding a collapsed casing in a well, the combination of a head having means for attaching the same to the lower end of a tool string, acollar having a swivel connection on the longitudinal axis of said head, a plurality of expander dogs attached to the collar toward one end so as to swing out at their other ends in a substantially radial direction, and having tapered noses for engaging the wall of the casing at the collapsed point, said tapered noses operating when engaging the wall 01": the collapsed casing to. prevent rotation of the collar, and means carried by the head for moving the expanding dogs outwardly to expand the collapsed casing. Signed at Los Angeles, Calif., this 31st 1928. LINTON A. LANGSTAFF.

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