US982059A - Underreamer. - Google Patents

Description

A. G. HBGGEM.

UNDERRBAMEB..

APPLIUATION FILED JAN.26,1909

Patented Jan. 17, 1911.

Cil

ALFRED G. HEGGELVI, 0F COR-AOLIS, ENNSYLV'ANIA, ASSIGNGR TO OIL VJELL SUPPLY COMPANY, GF ITTSBURG, PENNSYLVAN CRPOBATION OF PENNSYLVANIA.

UNDEREAMER.

Specification of Letters Patent.

Patented Jan. i7, i911.

To all whom it may concern:

lle it known that l, ALFRED G. Hneenn, a citizen ot the United States, residing Coraopolis, in the county of Alleghenyv and ite oi `Pennsjilvania, have invented cert:v `n uen.v and useful improvements in Underreainers; and l do hereby declare the Jrolloiving to be a full, clear, and exact description et the inventionl` such as Will enable others skilled in the artto Which it appertaius to make and use the same.

My invention relates to the construction of that class ot' devices known as underreaniers, which are employed for enlarging the bore ot rtesian and like drilled W lls ivhere casing is used and the tool is introduced and withdrawn through the casing. ln this class of devices, the reaming bits should not only be so connected to the stock or mandrel as to be expansible and collapsible, but the connections should be such as will permit the ready removal ot the bits .tor sharpening` when required. The bits and -their supports on the mandrel or stock should also be et' a character which Will insure the integrity oit the bits and their connections When subjected to the severe shocks and strains of service7 While the tool as a whole should be et such a character that it will readily tree itself from sand and silt xvh en it is desired to Withdraw said tool from the Well. The preferred torni oit this class ot' tools is one wherein the bit-stock or inandrel is provided with bit-slots having in their lateral Walls Ways for retaining` and guiding the bits, abutments to support the bits against shocks when in service, and a distance block to maintain the bits in an cxpanded or operative position. To such a mandrel or stock the bits are slidingly connected and are actuated by a spring` through the medium otl a cross-key or bar the ends ot which enter slots in the tangs oit the bits.

In service several points of Weakness have developed in the present constructions ot iniderreainers, leading, at times, to the loss of the bits in the Well and expensive iishing operations to remove said bits and thus reclaim the Well. Among the most important or' these detects are: Weakness of the stock adjacent to the bit receiving guide-Ways formed therein; Weakness of the bit-Shanks due to slotting the same for the reception ot a cross-key connecting the bits With the actuating spring; and detects in the form of distance block and bits Which prevent he cavity of the stock from readily freeing itseltl from sand and silt when the tool is vvithdraufn from the Well. rlfhis latter defeet often causes the tool to stick and neces lsitates the use et' drill jars Which, on account ot the packing ot the sand, are apt to detorin or shear ott the key or break the bitshank, and cause the loss of one or more of the bits in the Well.

To overcome these several defects in underreaniers is the object, of my present invention.

To effect the reinforcement of the stock at the points Where the lateral strains from the bit are resisted, i bevel the outer Walls of the bit Ways, so that said outer Walls shall form an obtuse angle, whereby an increase in the body of metal of the stock is effected and the depth of the Ways may be reduced; and such a construction embodies one teature of my invention.

To eitect the reinforcement of the bitshanks l dispense with slot and key connections between the bits and the actuating` and in lien thereof employ solid bit JIJL shank with an inwardly projecting over-hang which is adapted to engage a bit-block that is interposed between the bits and the actnating spring, whereby not only is the body of metal in the bit-shank increased at the point most liable to suffer fracture, but the bearing` and support of the bit on the abutment of the stock is also greatly increased: and such a construction embodies a second teature ot my invention.

To etfect the ready clearance or discharge ci sand, etc., from the cavity ot' the stock vvnien ivithdravv'ing the tool from the Well, the top ot the distance-block is inclined and thc lateral Walls thereof are tapered doivnivardly, whereby jarring operates to displace laterally any sand which may have acciunulated in the stock cavity and to permit its easy escape through the spaces between the bits and the side Walls of the distance block, said spaces, on account of the tapering form of the said distance block, attording increased opportunity tor the egress ot the sand as the bits slide downwardly: and

such a construction embodies a third teature ot my invention.

There are other, minor, features of inven- Cil longitudinal central section of the bit-stock,

showing the bits in side elevation, in an ei;- panded or operative position. Fig. 2 is a similar view ot the lower end ot the bitstoclr, the reainer-bits being in the position they occupy when being introduced in or withdrawn trein the casing; Fig. 3 is a longitudinal central section ot the lower end ot the bit-stoel; 'taken in a plane at right angles to Fig. 2; Fig'. l is a transverse section ot the bits and bit stock or mandrel, talen in the plane ot the line t-f.. l; Fig. is a. transverse section of the device, taken in the plane et the line Fig. l; Fig. 6 is a detail perspective view or the bit-block; and ljig. 7 is a detail perspective View of the upper end oit the bit-shank, showing the overhang` thereoiQ which engages the bitblock.

Like symbols refer to like parts wherever they occur.

l will new proceed to describe my invention incre fully so that others skilled in the art to which it appertains niay apply the same.

ln the drawings, A indicates the bitstoclr, B the reainingr bits which are slidiiigly arranged in the bit slots a of the stock7 C a tension spring for actuating the bits,

@sacas ways, which taper or decrease in width from below upward, are formed with the beveled walls 5f or so that the outer walls oit the ways i'orin an obtuse angle, such a construction resulting in an increased cross-section of metal in the stoel; at the points where the lateral strain et the bits is to be resisted.

and also enablingthe depth ot' said ways or and D a bit-block tor connecting'` the bits 1- with 'the bit-actuating` spring C.

The bit-stoel; or niandrel this provided with a central bore l Jlor the reception of the bit actuating' spring' C, the lower portion of said bore being' of sufficient dialneter to accoinniodate the spring', but. the upper portion thereo't being preferably formed vith decreased diameter, as at la, to thus forni a shoulder l" tor the support ot a bolt by which the bit actuating` tension spring is anchored to the bit-stock.

The stock er at its lower end is transversely and vertically slotted to torni the lateral slots o for the reception ot the rangs ot the bit and to also torni the distance blocl 2 :tor expanding; the bits and insintaining' than in operative position. This slotting of the steel; also results in forming' thereon upon or inner abutinents 3 which adjacent to their cutting edges.

llorincd in the lateral walls of the bitslots o1" the stock are ways 5 tor the guidance and lateral support of the bits.

recesses to be decreased.

ln order to cause the lateral displacement et any tine sand or like inatter which inay accumulate in the cavity ot the stock, the top surface or" the distance bloclr 2J is sloped or inclined5 as at Q; and in order to provide 'for the discharge ot the displaced sand the lateral. surfaces ot said distance bloei; are tapered downwardly and inwardly, as at 2b, so that as the bits descend to the collapsed position, as shown in `i`g'. 9, a clearance channel will be torined between the shanlrs ot the bits and the lateral surfaces et the distance block. The lower surface ot the distance block may be flat it desired.

The bits B have the usual lateral. shoulders or alnitnients (i which engage the abutnients fl on the lower cud ot' the stoel; fr, and are provided with lateral ribs i on the tanigs 7 which enter the ways 5 in the lateral walls oit the bit slot u olf the stock. 'llhe ribs 7 are beveled to correspond with the bevel l f1 on the y'all of the way 5, or guide rec The interior taces ot the shanlrs o'l the bits are cut bach or recessed. as at 8. to accountmdate the interi ediate distance block Q when the bits are drawn down and collapsed7 as indicated in Fig'. 2 et the drawijiulj, and tl c upper ends ot the bits project. inward to torni shoulders or overhannjs 9 which7 when the bits are in position in the stocln extend over and engage thc bitv bloclr D. Upon the upper and inner end ot cach bit-shank is a projection or nipple 5l which corresponds with the diameter ot the spring' receiving); bore ot the stock. These nipples are adapted and intended to enter said bore l and assist in supporting the bit against lateral strain and displacement: when in operation. rlhis ccnstriuztion of the bits not only leaves the bit tanpjs solid and therefore better adapted ed to res .et strains or crushing: torce, but also materially increases the bearingv area ot the upper ends oit the bits on the zii/utinents oit the stoclr. rthe und .rtaces said overhanegs 9 are preferably hollowed out slightly, but may be perfectly plain or tlat it desired, while their inner 'races are vertically recessed or slotted. as at El t' 01" the reception ot the stern l0 oit the bit bloclr l).

D slightly less width tran the width oit the bit-slot c in which it inoves. the arca ot the under surface ol the bit-block being approxiinately that ot the cross section ot that por- These l tion et the slot in the stoel; intermediate ol indicaties the bit-block which is ot j lOO the rcainer bits. rlhe bit-block is provided with a fiat bar stem l() having at its upper end an elongated eye or slot 10 for the reception of a hook on the lower end of tension spring C. intermediate of the block D and eye 10, preferably at the bottom of the eye, the stem. 10 is provided with an enlargement or collar 11, the function of which is to cause the bits B to Ydescend uniformly in case one bit should stick or for any reason tend to lag: behind the other.

The spring; C, by means of which the bits B, are held in place on the abutments 3 and 4f when the underreainer is in operation, provided at its lower end with suitable means, such as a hook c, for engaging the bitsbloclr D, and said spring is preferably anchored at its opposite end on the stock by means of an internally threaded plug or nut 121, and a threaded bolt 12, the head 12" of which engages the shoulder 1b in the upper end of the bore of the stock A.

1n assembling' the elements of the underreanier the hoolr c on the lower end of the tension spring C is entered in the eye 10a of the bit block D, and the spring is inserted in the bore 1 of the stock A. The spring is then anchored at its upper end to the stoel; by means of the bolt 1Q and plug` The spring` C having' been thus anchored on the stock the bit-block D is drawn down until the eye 101 emerges from the bore 1 of the stock into'the bit-slot a. thereof and a rod is passed through said eye below the hook c to hold the springextended. The bits B, B are next inserted in the bit-slots a, u from below, so that the ribs T on the bit shanks shall enter and pass up iu the ways 5. When the upper ends of the bit Shanks have reached the lower face of the bit-block D. the upper ends of the bit-Shanks zi are tilted outwardly, which the lateral play of the ribs 7 in the ways 5 permits, until the over-hangs E) pass the bit-block D, after which the bits may be tilted inwardly until. the over-hangs 9 thereof extend over and engage the said bit-block. Thereafter, upon withdrawing the rod which has been passed through the eye 10a of the bit block stem 10 to retain the spring' C extended, the reaction of the spring` will draw the bits D, B upward until the upper ends of the tangs t rest solidly on the abutments of the stock and tl e shoulders 6 engage the abut-ments 4l: on the lower end of stock A. In this movement of the bits the nipples or projections .9 on the upper ends of the tangs` enter the bore 1 of the stock, in which posit-ion they afford support for the bits during the operation of the tool, and also resist the inward movement of the bits resulting from wear of the cutting` edges thereof.

`When it is desired to introduce the tool into the casing the bits are drawn down into the position shown in Fig. 2 of the drawing,

when the underreainer will pass into and through the casing.

lf it is desired to remove a bit for sharpeninp or for any other purpose, the bits are first drawn down to the position shown in Fig'. Q and rod is then passed through the eye 10a of the bit-block D to hold the latter down and the springI C extended, after which either or both of the bits may be readily removed from the stock fr by reversing' the several movements of the bits noted in the foregoingl description of the manner of assemblingthe elements of the underreaincr.

ln withdrawing,T the underreamer from the well, the tool is lifted until the engagement of the outer surfaces of the bits with the lower end of the casing arrests the upward movement of said bits, while the `upward movement of the stock A continues. This causes the spring C to be put in tension, which permits the distance block D to ascend until it opposite the recesses S in the inner faces of the shanlrs, whereupon the bits D, B collapse and assume the position shown in Fig. This permits the bits to enter and pass through the casing.

Having thus described my invention, what I claim and desire to secure by Letter' latent is:

1. In an underreamer, the combination of a mandrel or stock having` bit-slots the lateral walls of which are provided with ways the outer walls o-f said ways meeting at an obtuse angle, and sliding reamer bits each provided with laterally projecting` ribs said ribs having a cross section conforming to that of the ways in the walls of the bitstock.

2. 1n an underreainer, the combination of a mandrel or stock which is slotted trans versely to form communicating bit slots having their lateral walls provided with ways, reamer bits movable on the stock, each of said bits having laterally projectingribs movable in the ways of its bit slot and having a solid tang formed with an inwardly projecting overhang whereby it is supported by a bit block, a bit block slidable in the slot of the mandrel intermediate of the reanier bits, the area of the under surface of said bit block l eing` approximately that of the cross-section of that portion of the slot which. is intermediate of the reamer bits, and means on the bit stock for maintaining the reainer bits in expanded position.

3. In an underreamer, the combination of a mandrel or stock having a bit-slot, reamer bits and a bit-block slidable in the said bitslot, the reamer-bits having overhangs which engage the bit-block, and the bit-block having a stem provided with a collar which projects over the overhangs of the reamer-bits.

4. In an underreamer, the combination of a mandrel or stock which is slotted transversely to form communicating bit slots having their lateral walls provided with ways, a distance block at the lower end of the mandrel for maintaining the reamer bits in expanded position, said distance block having its upper surface inclined, reamer bits movable on the stock, each of said bits having laterally projecting ribs movable in the ways of its bit slot and having a solid tang formed with an inwardly projecting overhang whereby it is supported by a bit block, and a bit block slidable in the slot of the mandrel intermediate of the reamer bits, the area of the under surface of said bit block being approximately that of the cross section of that portion ot' the slot intermediate of the reamer bits.

5. In an underreamer, the combination of a mandrel or stock which is slotted transversely to form communicating bit-slots having their lateral walls provided with ways, a distance block at the lower end of the mandrel for maintaining the reamer bits in expanded position, said distance block having its upper surface inclined and lateral surfaces which converge from above downward, reamer-bits movable on the stock each of said bits having laterally projecting ribs movable in the ways of its bit slot and having a solid tang formed with an inwardly projecting overhang whereby it is supported by a bit block, and a bit block slidable in the slot of the mandrel intermediate of the reamer-bits, th-e area of the under surface of said bit-block being approximately that of the cross section oi that portion oit' t-.he slot y which is intermediate of the reamer bits.

6. ln an underreamer, the combination of a mandrel or bit stock having a. bore, bitslots and lateral abutments formed by said bit-slots, a distance block at the lower end of the mandrel for maintaining the reamei'- bits in operative position, 4a bit-block or bit support movable in the slot of the mandrel above said distance block, and i'eamer-bits supported by said bit-block and having on their upper surfaces which engage the abutments projections which enter the boi'e ot' the stock between said abutments.

7. In an underreainer, the combination of a mandrel or stock having a bore, bit-slots and abutments adjacent to the bore and in planes at right angles thereto, a distance block at the lower end of the mandrel which maintains the reainer-bits in operative position, a bit-block or bit-support having a stem and which is movable in the slot or' the mandrel above the distance block, and reamer-bits each having` on its upper end an inwardly projecting overhang which engages an abutment on the stoel; and which takes over the bit-block and is supported thereby, said overhang` having a projection which enters the bore of the stoclr.

8. A mandrel or stock for underreamers said mandrel having a slot which extends transversely therethrough forming communicating bit slots, the lateral walls of the bit slots provided with ways the outer walls of which form an obtuse angle, said ways adapted to receive ribs of corresponding cross-section on reamer bits which are adapted to co-act with the stock.

In testimony whereof l aiiix my signature, in presence of two subscribing witnesses.

ALFRED G. HEGGEV.

Vitnesses Louis C. SANDS, W. W. ANDERSON.

Images