US1234041A - Sectional slip. - Google Patents

Description

W. G. KNAPP.

SECTIONAL SLIP.

APPLICATION FILED JAN. 9. I913.

Patented Jul 17, 1917.

WILLIAM a. KNAPP, or ALHAMBRA, CALIFORZNIA.

SECTIOINAL SLIP.

Application filed January 9, 1913. Serial'No. 741,109.

To all whom it may concern:

Be it known thatI, WILLIAM G. KNlAPP,

Y a citizen of the United States, residing at Alhambra, in the county of Los Angeles and State of California, have invented new and useful-Improvements in Sectional Slips, of

fwhich the following is a specification.

In oil well construction is-necessary to provide means for supporting the casing of the well during the operation of drill ng the well. It is also necessary at times during the drilling operation to raise and lower the casing. Ordinarily there is provided for this purpose a supportlng member, commonly termed a. spider, which rests upon the floor of the derrick, or, where the derrick is provided with a cellar, upon the floor of the cellar. -.}.This' spider is provided with a central opening through which the cas ng extends vertically, and between the casing and the wall of the central opening of the spider are provided a series of segments each having an inner gripping face adapted to engage the casing and a beveled outer face adapted to engage the wall of the opening in the spider. The angle of the beveled 1nner face of the opening of the spider and the outer face of each slip has been determined by experience to be about three inches to a foot. Should this angle be too great, the weight of the casing would cause the slips to back away from the caslng, thereby permitting the casing to slidedownwardly through the slips. If the angle 1s made too small, the binding of the slips about the casing is. so great that the casing is plnched. When a great length of casing is supported by the usual form of slips, the slips become wedged so tightly in the spider that the casing when lifted, as is necessary at times during the drilling operation, raises the slips and the spider. It then becomes necessary to use a sledge or other heavy object to disengage the spider and slips, which operation places a great strain upon the casing and lifting devices and causes liability of damage to some portion of the mechanism.

One of the main objects of my invention is to provide slips made. in sectional form which will immediately release upon raising the casing, without raising the spider or supporting n'iember.

Another object of my invention is to provide slips in which the casing gripping face may be made of maximumlength.

I Referring to the drawings, which are for illustrative purposes only:

ligure 1 1s a perspective View of a supporting member or spider provided with slips embodying a form of my invention.

Fig. 2 is a sectional view on line-a2 m Fig. 1. f

Fig. 3 is a perspective view of one of the slips showing the casing gripping face thereof.

F1g.4 is a perspective view of one of the sllps showing the outer face of the slip.

Fig. 5 is a diagrammatic view illustrating the manner of using the spider and slips for supporting the well casing.

My invention resides in general terms in producing an improved slip. of sectional -form,'be1ng constructed of two or more parts, one of WhlCh' is an inner memberadapted: to engage the casing and another being an outer member having a tapered outer face adapted to engage the spider or supporting member, the contacting faces of the two parts being tapered at "a greater angle' than the spider engaging face of the outer member.

l designates a supporting member or spider consisting of a heavy metal, casting having a circular body portion 2 provided with extensions or arms 3, each arm 3 being provided with a ring 4 which extends through an opening 5 in the respective arms, the rings a being provided to facilitate the lifting or moving of the spider. The spider is provided with a round central opening 6, the wall 7 of which tapers downwardly and inwardly, as clearly illustrated in Fig. 2 of the drawing. .lVithi-n the central opening 6 of the spider is arranged, in the form shown, three segmental sectional slips 10, each consistingof an inner or casing gripping mem ber 11 and an outer or spider gripping member 12. The outer. face 13 of the spider gripping member 12 is beveled at the same angle as the wall of the opening 6 in the spider. The angle shown, being about three inches to one foot, has been determined to Specification of Letters Patent. P t t July m, 19.1%

ably g ater angle than the outer face 13 of the spi er gripping member -12. The inner face '14 of each member 12 is staggered, as indicated in Figs. 2and 3, and provlded -.with a shoulder 15. Each casing gripping member 11- is of greater length than the re spective spider gripping members 12, be ng provided with an upper flange 17 whichrests upon the upper end of its associated outer member 12, and-a lower flange 16 which extends under the lower end of the respective outer members 12, there being a space between the lower end of the mem-- bers 12 and the respective flanges 16 when the upper flange 17 is resting'upon the upper end of the respective outer members 12.

The casing gripping members 11 are each" -provided with an outerstaggered beveled face 18 of the same angle as the inner face of the members 12, the face 18 of each member 11 being provided with a shoulder 19, as clearly shown in Fig. 2, there being provided a sufiicient distance between the shoulders 15 on the members 12 and shoulders 19 on the members 11 so that the same at no time come into contact with each other. In each flange 17 of the respective inner members 11 is provided an opening 20 throughwhich downwardly extends the threaded end 21 of an eye 22, the threaded end 21- extending into the spider gripping member 12 of the respective slips. The lower flange 16 ofeach inner member 11 is provided with an opening 23 through which extends a pin 24, the inner end of which is threaded into the lower end of the respective outer members 12. The eyes 22 and pins 24 serve to keep the two parts of each slip, namely, the casing gripping member 11 and the spider gripping member. 12,.' in proper relation to each other.' Each easing gripping member 11 is provided with a series of circular teeth 26, the pointsof which are extended upwardly and cut at intervals, as indicated at 27, thereby providing a plurality of teeth ries of corners or edges '30, thereby adding additional length of life to the gripping action of the slips, the cuts 27 being preferably arranged in staggered form, as indicated in Figs. 2 and 3.

The device is used in the following manner:

As illustrated in Fig. 5' the spider 1 is placed upon the floor of the derrick indicated at 40, the casing 41 extending through the spider as shown with the slips 10 within the central opening 6 ofthe spider between the same and the casing 41. The weight 41 is lowered the operators take hold of the eye bolts 22 and pull the outer or spider.

g pping members 12 upwardly until they are in substantially the position shown in Fig. 2, the inner members 11 resting loosely by means of their flanges 17 upon the top of the members 12. The operators hold the members 11 and 12 in the same relative position as the casing is lowered. This lowering of the casing causes the teeth 26 to grip the casing and the members 11 and 12 are carried down together and wedged in the spider 1 gripping the casing firmly at the same time. There is no movement of the inner member 11 with relation to the outer member 12, the two members moving downwardly with the casing, the only sliding movement being on the-beveled face 13.

,It is a well known fact that when metal surfaces are ground together under heavy pressure they tend to becomewelded together due probably to a locking action of the surfaces. This action is known in mechanics as seizing. In the ordinary form of slip having a single wedge this seizing tends to freeze the wedge to the spider and makes the removal thereof very diflicult. It is to obviate this difficulty which is oftenv so serious as to call for vigorous action with asledge hammer that the slips 10 are made in two parts 11 and 12. There being no sliding between these members but merely an expansive action they do not seize but part readily and cleanly. Moreover the wedging angle between the members 11 and 12 being greater than the angle of the surface 13 the tendency to stick is greatly reduced.

\Vhen it is desired to raise the casing, any of the ordinary or well known forms of elevating means may be employed, and as the casing moves upwardly the outer face 18 of each inner member 11 immediately becomes disengaged from the inner face 14 of each outer member 12, due to the great angle of the respective adjacent bearing faces which immediately permits an expanding action of the inner members 11. The inner members 11 thereupon drop away .or become disengaged from the casing.

Should the weight of the casing have caused the teeth of the inner members 11 to enter the casing, thereby causing the inner men bers 11 to remain in engagement with the casing after the outer bearing face of each bearing faces of the inner and outer memb'ers l1 and 12 respectively, the striking of the flange 16 against the lower end of the respective outer members 11 would cause disengagement of the outer members 12 and the spider, and at the same time cause disengagemen-t of the inner members 11 with the attached 'to the rings 4 shown onthe spider.

What I claim is: 1. A casing support comprising a supporting member having a beveled opening therein, a series of segmental slips in said opening, each consisting of relatively movable inner and outer members, a flange on each inner member at the upper end thereof extending over the upper'end of its associated outer member, and a flange on each inner member at the lower end thereof ex tending under the lower end of its asso-' ciated outer member, said flanges being adapted to alternately engagethe opposite the outer face of the .outer member, and a ends of said outer members. 4

2. A sectional slip of segmental form comprising an inner member, an'outer member connected to said inner'member to permit relative movement therebetween, said outer member having an outer beveled face, said members having slidably engaging faces bev- 1 eled at anangle greater than the angle of I flange on the inner member adapted to engage the top of the outer member.

3. A sectional slip of segmental form comprising an inner member, an outer member connected to. said inner member to ermit relative movement therebetween, sai outer member having an outer beveled face, said members having slidably engaging faces beve eled at an angle greater than the angle of the outer face of the outer member, a flange 0n the inner member adapted to engage the top of the outer member, and a flange on the inner member adapted to engage the lower end of the outer member, said flanges being arranged to alternately engage the opposite ends of said outer member.

4. A sectional slip comprising an outer member having an outer beveled face and a stepped inner face beveled at an" angle greater than the outer face, an inner member having a toothed inner face and a stepped outer face corresponding to the inner face of the outer member, a flange extending outwardly from both ends of the innermemb'er over the respective ends of'the outer member, said flanges being adapted to alternately engage the opposite ends of the outer member, and an eye bolt secured to the up per end of the outer member extending through an opening in the inner member.

5. A casin support comprising a supporting member having a beveled opening therein, support gripping members placed therein, 'means whereby said'support grippin members may be supported independent y of said supporting member, casing. gripping members between said support gripping members and the casing, and means by which said casing gripping mem bers may be supported on said support grip-' ping members.

6. A casing support comprising a supporting member having a beveled opening therein through which the casing passes, wedge shaped support gripping members placed in said opening, means by which the opening, casing gripping members between said support gripping members and the casing, means whereby said support gripping members may be supported out of contact with the conical surface of said conical opening in said supporting member, and flanges V on said casing gripping membersadapted to limit the downward movement of said casing gripping members with relation to the 4 support gripping members.

8. A casing support comprising a supporting member having a beveled opening therein through which the casing passes; 4

outer wedges in this opening, inner wedges between the outerwedges and the casing, means whereby said outer wedgesmaybe supported out of contact with the walls of said beveled opening, and means formed on the inner wedges whereby said inner wedges may be-suported on the outer wedges.

9. A casing support comprising a supporting member having a beveled opening through which the casing passes, outer wedges in this opening, inner wedges in this opening, and eye bolts secured in the top of said outer wedges by means of which the weight of the outer wedges may be supported independent of the supporting member.

10. A casing-supportcomprising a sup-- porting member having a beveled opening through which the casing .passes, outer wedges in this opening, inner wedges'in this opening, flanges on said inner wedges projecting out over the outer wedges, and means on said outer wedges whereby the weight of said outer wedges may be, supported from above independent of the sup- 'which are independent of. said supporting porting member.

f 11. A casing support comprising a supporting member having a beveled opening through which the casing passes, outer wedges in this opening, inner wedges in this opening, flanges on said inner wedges projecting out over the outer wedges, and eye bolts fixed in the top of said outer wedges by means of which the weight of said wedges may be supported independent of the sup porting member. W p

12. A casing support comprising a supportingmember having a beveled opening through which the casing passes, outer wedges in this. opening, inner' wedges in this opening, flanges on said.inner:wedges projecting out overthe outer wedges flanges on said inner members projecting beneath 'the outer members, and means on said outer wedges for attaching supporting means member.

.13. A casing support comprising a supporting member having a beveled opening through which the casing passes, outer wedges in this opening, inner wedges in this opening, flanges on said inner wedges projecting out over the outer wedges, flanges on said inner members projecting beneath the outer members, and eye bolts on said outer wedges to which independent supporting means may be attached.

14. A sectional slip adapted to be used between a cylindrical casing and a conical hole in a supporting member said sli comprising an outer member, means w ereby' said outer member may be supported independently of said casing or said support, an inner member, and means formed on the outer member for supporting said inner 'member.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this th day of December, 1912. V

WILLIAM G. KNAPP. In presence of FRANK L. A. GRAHAM,

LORRAINE E. Dmmow.

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