US2726848A

US2726848A - Logging sub

Info

Publication number: US2726848A
Application number: US458413A
Authority: US
Inventors: Richard F Montgomery; Nicolaas L Koot; Marion A Garrison
Original assignee: KOOT
Current assignee: KOOT
Priority date: 1954-09-27
Filing date: 1954-09-27
Publication date: 1955-12-13
Anticipated expiration: 1972-12-13

Description

2 Sheets-Sheet l R. F. MONTGOMERY ET AL LOGGING SUB Dec. 13, 1955 Filed Sept. 27, 1954 l ab@ Dec. 13, 1955 Q F, MONTGOMERY ET A1. 2,726,848

LOGGING SUB 2 Sheets-Sheet Filed Sept. 27, 1954 tannini/.M3332 tion. section 13 and the mandrel section 16, respectively, are

United States Patent O LoGGlNG SUB Richard F. Montgomery, Midland, and Nicolaas L. Koot, Odessa, Tex., and Marion A. Garrison, South Pasadena, Calif., said Garrison assignor to said Montgomery and said Koot Application September 27, 1954, Serial No. 458,413

19 Claims. (Cl. 255-28) 'This invention relates to a novel sub structure for use 'in a drill string and more particularly to a telescoping sub adapted to cooperate with a well caliper, such as that disclosed in a copending application to Richard F. .Montgomery and Nicolaas L. H. Koot, entitled Caliper- "ing Method and Apparatus," Serial No. 331,916, filed January 19, 1953.

lt is the principal object of this invention to provide :a telescopic sub for use in a drill string, wherein said :sub may be latched in collapsed relation to transmit torque to a bit, and wherein said latch may be released to per- 4mit extension thereof to uncover suitable openings through which caliper `arms may be extended to caliper `the well bore diameter as Vthe drill string is withdrawn therefrom.

A further object of this invention is to provide a sub :as set forth in the preceding object wherein said sub may be relatched if the latch should be inadvertently ytripped or if it is desired to' remove theV ealipering tool and resume drilling.

The preferred form of our invention is described in the following detailed specification and illustrated by way of example in the accompanying drawings wherein:

Fig. l is a longitudinal sectional view of a sub embodying the principles of our invention.

Fig. 2 is a partial longitudinal section of enlarged scale similar to that shown in Fig. 1, and illustrates the details of the latch assembly portion thereof with the latch in locked relation.

Fig. 3 is a similar view to Fig. 2 and shows the logging tool seated in the sub with the latch released and the sub partially extended.

Fig. 4 is a similar view to Fig. l and shows the logging tool in place and the sub fully extended.

Fig. 5 is a sectional View taken on line 5 5 of Fig.3.

Fig. 6 is a sectional view taken on line 6-6 of Fig. 3.

Referring now to the drawings, wherein similar reference numerals are used to designate similar parts throughout the various views shown, the logging sub comprises two telescoping parts, an outer housing generally indicated at 10, and an inner tubular mandrel generally indicated at 11.

The outer housing is composed of two

sections

12 and 13 threadedly connected to each other. Similarly, the mandrel is composed of three

sections

14, 15 and 16 threadedly connected together. As best seen in Fig. 3, the lower end of the housing section 13 is formed with depending lugs 17 which intermesh with corresponding recesses 18 formed in the lower section 16 of the mandrel 11, to prevent relative rotation between the members lo and 11 when said members are in collapsed rela- The

meeting surfaces

48 and 49 of the housing tapered upwardly and inwardly, and the lower inner corner of the lugs 17 are chamfered, as shown at S0, for purposes which will be described presently. Two O-

ring seals

19 and 20 are mounted one above the other in suitable grooves provided in the exterior surface of 2,726,848 Patented Dec. 13, 1955 ICC the mandrel section 16, and are adapted to sealingly e'ngage the' inner surface of the housing section 13 to provide a seal between the mandrel 11 and housing 10,- when said members are in collapsed relation.

Referring now to Fig. 2, a latch mechanism normally retains the housing 10 and the mandrel 11 in their collapsed relation. The latch comprises a plurality of latch fingers 21 pivotally mounted in suitable longtiudinally extending slots 22 provided in the mandrel section 16. The latch fingers 21 are each pivotally mounted adjacent their mid-points on pivot pins 23. Each of the latch fingers 21 has an outwardly extending portion 24 adapted to hook over the upper end of the housing section 13. The upper end of the mandrel section 16 is counterbored as indicated at 25. A sleeve 26, having an outwardly extending flange portion 27 adjacent its upper end, an annular outwardly extending boss 28 adjacent its mid-portion and an outwardly extending ange 29 adjacent its lower end, is slidably mounted in the counterbore 25, the outer diameter of the

flanges

27 and 29 and the boss 28 each being equal. Said outer diameter is such that these parts slide on the inner wall of the counterbored portion 25 of the mandrel section 16. The annular boss 28 is adapted to abut the inner surfaces of the upper ends of the latch fingers 21 and maintain said fingers in latched relation with the upper end of the housing section 13. A spring 30, confined between the shoulder 31 formed by the lower end of the counterbore 25 and the lower end of the sleeve 26, normally urges the sleeve upwardly to its locking position. When in its locking position, the upper end of the sleeve 26 abuts the lower end of the mandrel section 15. The upper end of the sleeve 26 is provided with a downwardly and inwardly beveled seat 32, the purpose of which will be described presently.

A plurality of locking fingers 33 are each pivotally mounted on a plurality of pivot pins 34 in the slots 22 below the latch fingers 21. A plurality of leaf springs 35 are each fastened at one of their ends to the mandrel section 16 below one of the slots 22. The other end of each spring 35 bears against the outer surface of the lower end of one of the lock fingers 33 and tends to rotate said lower end inwardly into the plane of movement of the flange 29 on the lower end of the sleeve 26. The outer surfaces of the upper portions of the lock fingers 33 normally bear against the inner surface of the housing section 13' and prevent inward rotation of the f lower ends thereof. As best seen in Figs. 3 and 4, when the mandrel 11 is extended relative to the housing 10, the lock fingers 33 are no longer confined by housing section 13 and rotate under the influence of the leaf springs 35 so that the lower ends of the lock fingers 33 will catch on the upper surface of the lower ange 29 of the sleeve 26 to prevent the spring 30 from raising the sleeve 26 to its latch locking position'.

A thrust bearing 46 is confined between the lower end of the mandrel section 14 and an upwardly facing shoulder 47 formed adjacent the upper end of the mandrel section 15. As best seen in Fig. 4, the upper end of the housing section 13 abuts the lower surface of the thrust bearing 46 when the assembly is in its extended relation.

A plurality of aligning pins 36 is mounted in the walls of the mandrel section 16 and extends radially inward horizontal plane located below the rst plane.

caliper tool 38 adapted to be used with the logging sub.

The caliper tool 38 is provided with three pivotally mounted caliper arms 39 adapted to pivot outwardly through three longitudinally extending slots 40 provided in the walls of the mandrel section 15. In order to maintain the slots 4t) in proper orientation with respect to the aligning pins 36, a lock member 41 engages a suitable notch 42, formed in the upper end of the mandrel section 16, and is fastened to the mandrel section by a plurality of cap screws 43. The caliper tool 38 is provided with a downwardly facing beveled shoulder i4, which is adapted to seat on the beveled seat 32 formed on the upper end of the sleeve 26.

In the use of the sub, the parts are assembled in the positions illustrated in Fig. l. A bit (not shown) is connected to the lower end of the mandrel section 16 in the usual manner and the upper end of the housing section 12 is connected to the lower end of a drill string indicated at 4S. The assembly is lowered into the well and drilling is performed in the usual manner by rotating the drill string. The rotation of the drill `string is transmitted from the housing 1.0 to ,the mandrel 11 through the interlocking lugs and

recesses

17 and 18, respectively. Since the mandrel 11 and housing 10 are sealed to each other by the O-ring `

seals

19 and 20, duid may be circulated downwardly therethrough, out through the bit and back up the annular space surrounding the string in the usual manner.

When it is desired to remove the string from the Well and simultaneously log the well diameter, .the Vcaliper tool 38 is lowered or dropped through the well string. When the shoulder 44 on the caliper tool seats on the seat 32 on the upper end of the sleeve 26, continued downward movement of the caliper tool 38 will force vthe sleeve downwardly to the position shown in Fig. 3, wherein the boss 28 moves out of engagement with KVthe inner surface of the upper ends of the latch fingers `21 and the lower surface thereof contacts lthe innersurface of the lower ends of the latchjiingers 2,1 to rotate the upper end of the latch lingers inwardly utorelease the Ymandrel 11.for .outward extension relative to-theghousing 10. As the caliper 38 seats in thesub, the grooves 37 on the lower end of the :caliper 38 cooperate with the Aaligning pins 36 to rotate the caliper and automatically bring the caliper arms 39 into register-with the slots 40.

As the well string is raised, ;the housing y10 is raised therewith relative to the mandrel 11 Auntil the upper surface of the housing 13 contacts the lower surface of the thrust bearing 46. At lthis time the slots :40 are located completely below the lower end of the housing -10 and the caliper arms 39 are permitted to swing outwardly into contact with the bore wall. It will be appreciated that since the lugs 17 are no longer in engagement with the recesses 18, the drill string maybe rotated for dismembering purposes without rotating lthe mandrel 11 and the caliper tool 38 seated therein.

If the latch fingers`21 should be trippedaccidentally, or it is desired to remove vthe caliper and relatch the assembly to continue drilling, this may be accomplished by merely setting down Weight on the drill string since the lock fingers 33 have been rotated by thev leaf springs 35 into the position shown in Fig. 3. In this position, the lock fingers 33 will hold the sleeve 26 down when the caliper 3S is removed. Upon subsequent downward movement of the housing 10, either the chamfer 50 on the lower ends of the lugs 17 or the upwardly and inwardly inclined surface 48 on the lower end of the housing will rotate the upper ends of thelatch fingers 21 inwardly. Further downward movement of the housing 10 will rotate the upper ends of the lock fingers 33 inwardly to release the sleeve 26 for upward movement under the influence of the spring 30, to force the upper ends of the latch fingers 21 outwardly to again hook over the upper end of the housing section 13.

From the foregoing description it may be seen that we have provided a novel telescoping sub structure which may be inserted into a drill string immediately above a bitand which is adapted to cooperate with a suitable caliper tool for logging the well as the drill string is withdrawn therefrom, and wherein said sub may be locked in collapsed relation to transmit torque from said drill string to said bit, and wherein lsaid sub may be unlatched to permit extension thereof to calipering relation.

While we have shown and described the preferred form of our invention, itis obvious that various changes may be made therein by those skilled in the art without departing from the spirit o f the invention as defined in the appended claims.

Having thus described our invention, what we claim and desire to secure by Letters Patent is:

l. In a logging sub adapted `to be inserted in a drilling string, a housing, a tubular mandrel telescopically rcceived in said housing, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hook-shaped latch fingers pivotally mounted on said mandrel adjacent their mid-portions and adapted lto hook over said upwardly facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an Iexternal boss on said sleeve adapted to bear against the upper inner surface of said latch lingers and maintain .said fingers in latching relation when said sleeve is in its uppermost position and to bear against the lower inner surface of said latch fingers to rotate the latch fingers to release position when said ysleeve moves downwardly.

2. In a logging sub adapted to bc inserted in a drilling string, a housing, a tubular mandrel telescopically received in saidhousing, a pair ofO-ring seals mounted on said mandrel and vsealingly engaging the lower inner surface of said housing when `said mandrel and salti housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, Asaid-latch .means :comprisin g an upwardly facing internal `shoulder in said housing, a plurality of hook-shaped latch fingers Ipivotally mounted on said mandrel adjacent their mid-portions and adapted to hoo?. over said upwardly facing shoulder, a sleeve slidably mounted for .vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch fingers and maintain said lingers in latching relation when `said ,sleeve is in its uppermost position and to bear against the lower inner surface of said latch fingers to rotate the latch'fingers to release position when said sleeve moves downwardly.

3. In a logging sub adapted to be inserted in a drilling string, a housing, Aa tubular mandrel telescopicalb rcceived invsaid housing, a pair oflO-ring seals mounted on said mandrel rand `sealingly engaging the lower inner surface lof said -housing .when `said mandrel and said housingare inv telescoped relatiolnlieleasable latch means adapted to maintain saidmandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hook-shaped latch `fingers pivotally mounted on said mandrel adjacent their Vmidi-portions and adapted to hooi: over said upwardly -facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch fingers and maintain said `iingers in latclr relation when said sleeve isy in 4 its uppermost posities-t andl to,bear"againsththelowcrinner surface of said latch fingerstoY rotate ythe latchifingersrto release position when said sleevewrnoves downwardly, a plurality of longitudinally extending slots in r saidmlandrel above said latch fingers adapted tobelunoveredtopermit the passage of logging .elements therethrough `when said mandrel and housing are in extended relation.

4. n a logging sub adapted to beinserted' in a drilling string, a housing, a tubular mandrel telescopically received in said housing, a pair of O-ring seals mounted on said mandrel and sealinglyl engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hook-shaped latch fingers pivotally mounted on said mandrel adjacent their mid-portions and adapted to hook over said upwardly facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch fingers and maintain said fingers in latching relation when said sleeve isin its uppermost position and to bear against the lower inner surface of said latch fingersto rotate the latch fingers to release position when said sleeve moves downwardly, a plurality of longitudinally extending slots in'said mandrel above said latch fingers adapted to be uncovered to permit the passage of logging elements therethrough when said mandrel and housing are in extended relation, and a plurality of radially inwardly extending aligning pins in the lower portion of said mandrel, one of said pins at one horizontal plane and two pins in a lower plane one directly below said one pin and the other spaced circumferentially 120 therefrom, said pins being adapted to cooperate with a suitably shaped groove on a logging tool to align the logging elements thereof with said slots.

5. In a logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, a pair of O-ring seals mounted on said mandrel and sealingly engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hook-shaped latch fingers pivotally mounted on said mandrel adjacent their mid-portions and adapted to hook over said upwardly facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch fingers and maintain said fingers in latching relation when said sleeve is in its uppermost position and to hear against the lower inner surface of said latch fingers to rotate the latch fingers to release position when said sleeve moves downwardly, a downwardly and inwardly tapered seat on the upper end of said sleeve adapted to receive a logging tool dropped through the drilling string, a plurality of longitudinally extending slots in said mandrel above said latch fingers adapted to be uncovered to permit the passage of logging elements therethrough when said mandrel and housing are in extended relation, and a plurality of radially inwardly extending aligning pins in the lower portion of said mandrel, one of said pins at one horizontal plane and two pins in a lower plane one directly below said one pin and the other spaced circumferentially 120 therefrom, said pins being adapted to cooperate with a suitably shaped groove on said logging tool to align the logging elements thereof with said slots.

6. in a logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, a pair of O-ring seals mounted4 on said mandrel and sealingly engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, Va plurality of hook-shaped latch fingers pivotally mounted on said mani adapted to bear against the upper inner surface of said latch fingers and maintain said fingers in latching relation when said sleeve is in its uppermost position and to bear against the lower inner surface of said latch fingers to rotate the latch fingers to release position when said sleeve moves downwardly, a downwardly and inwardly tapered seat on the upper end of said sleeve adapted to receive a calipering tool dropped through the drilling string, a plurality of longitudinally extending slots in said mandrel above said latch fingers adapted to be uncovered to permit the passage of logging elements therethrough when said mandrel and housing are in extended relation, a plurality of radially inwardly extending aligning pins in the lower portion of said mandrel, one of said pins at one horizontal plane and two pins in a lower plane one directly below said one pin and the other spaced circumferentially therefrom, said pins being adapted to cooperate with a suitably shaped groove on a logging tool to align the logging elements thereof with said slots, and means on the lower end of said housing adapted to interengage with means on said mandrel when said mandrel and housing are in telescoped relation to prevent relative rotation therebetween.

7. In a logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, a pair of O-ring seals mounted on said mandrel and sealingly engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means; adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardlyY facing internal shoulder in said housing, a plurality of' hook-Shaped latch fingers pivotally mounted on said man-4 drel adjacent their mid-portions and adapted to hook over` said upwardly facing shoulder, a sleeve slidably mountedl for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeveadapted to bear against the upper inner surface of saidl latch fingers and maintain said fingers in latching relation when said sleeve is in its uppermost position and to bear` against the lower inner surface of said latch fingers to rotate the latch fingers to release position when said sleevel moves downwardly, a downwardly and inwardly tapered seat on the upper end of said sleeve adapted to receive a calipering tool dropped through the drilling string, a plu-- rality of longitudinally extending slots in said mandrel above said latch fingers adapted to be uncovered to permit' the passage of logging elements therethrough when said mandrel and housing are in extended relation, a plurality of radially inwardly extending aligning pins in the lower' portion of said mandrel, one of said pins at one hori Zontal plane and two pins in a lower plane one directly below said one pin and the other spaced circumferentially 120 therefrom, said pins being adapted to cooperatei with a suitably shaped groove on a logging tool to align the logging elements thereof with said slots, means on` the lower end of said housing adapted to interengagel with means on said mandrel when said mandrel and boils-- ing are in telescoped relation to prevent relative rotation` therebetween, a downwardly facing thrust bearing:

' mounted on said mandrel adjacent the upper end thereof',

said thrust bearing being adapted to abut said upwardlyY facing shoulder in said housing when said mandrel and' housing are in extended relation.

8. In a logging sub adapted to be inserted in a drillingn string, a housing, a tubular mandrel telescopically re ceived in said housing, releasable latch means adapted tomaintain said mandrel and housing in telescoped relation,

said latch means comprising an upwardly facing internal, shoulder insaid housing, a plurality of hook-shaped latch fingers pivotally mounted on said mandrel adjacent their` mid-portions and adaptedrto hookover said upwardly facing shoulder; a sleeve slidably mounted for.vertical movement frornan upper to a lower position within said,

housing to move downwardly past said latch fingers, saidv lcclt fingers beingadapted to be contacted by the lower end of said housing and rotated thereby to release said sleeve for upward movement to relatch said latch fingers, and means normally urging said sleeve toward its uppermost position.

9. In a logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, a pair of O-ring seals mounted on said mandrel and sealingly engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in tele-V scoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hooleshaped latch fingers pivotally mounted on said mandrel adjacent their mid-portions and adapted to hook over said upwardly facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch fingers and maintain said fingers in latching relation when said sleeve is in its uppermost position and to bear against the lower inner surface of said latch fingers t0 rotate the latch fingers to release position when said sleeve moves downwardly, releasable lock fingers pivotally mounted on said mandrel below said latch fingers, said lock fingers being adapted to hold said sleeve in its lowermost position to permit said housing to move downwardly past said latch fingers, said lock fingers being adapted to be contacted by the lower end of said housing and rotated thereby to release said sleeve for upward movement t0 relatch said latch fingers, and means normally urging said sleeve toward its uppermost position.

l0. ln a logging sub adapted to be inserted in a drilling string. housing, a tubular mandrel telescopically received in said housing, a pair of 0-ring seals mounted on said mandrel and sealingly engaging the lower inner surface of said housing `when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hookshaped latch fingers pivotally mounted on said mandrel adjacent their mid-portions and adapted to hook over said upwardly facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch fingers and maintain said fingers in latching relation when said sleeve is in its uppermost position and Vto bear against the lower inner surface of said latch fingers to rotate the latch fingers to release position when said sleeve moves downwardly, releasable lock fingers pivotally mounted on said mandrel below said latch fingers, said lock fingers being adapted to hold said sleeve in its lowermost position to permit said housing to move downwardly past said latch lingers, said lock fingers being adapted to be contacted by the lower end of said housing and rotated thereby to release said sleeve for upward` movement to relatch said latch fingers, means normally urging said sleeve toward its uppermost position, and a plurality of longitudinally extending slots in said mandrel 8 above Said .lath;nsereadapted, mbe. uncovered, t0 permit the passageof1loggingelernents tlierethrr'iughV when said mandrel anclhousing are nextendedrelation 1l in ,alogging subadaptedtobefinserted in a drilling string, a,hou sing, a, tub u la r mandrel telescopicallyreceived -facing shoulder, a sleeve slidably mounted for vertical movement 'from ,an, upper Yto a lower position within said mandrel, an external b oss ,on .said sleeve adapted to bear against the upper inner` surface of said latch fingers and maintain saidV fingers inlatehingrelation when said sleeve is Vin its uppermost positionand to bear against the lower innersurface `of said latch fingers to rotate the latch fingers to releaseposition when said sleeve moves downwardly, releasable loclcfingers pivotally mounted on said mandrel belowlsaid latch fingers, saidV lock fingers being adaptedto hold said .sleevein itsiowermost position to permit `said',housing,to `move,downwardly past said latch fingers,lsaid' loclpfingers being adapted to be contacted by the lower end of -said housing and rotated thereby to release said sleevey for upward movement to relatch said latchfingers, means norrnally urging said sleeve toward its uppermost position, a plurality of longitudinally extending slots in said mandrel abovesaid latch ngers adapted to be uncovered to permit the passage of logging elements .therethrough when said mandrel and housing lare in extendedy relation, and a plurality of radially inwardly/ extending aligning pins in the lower portion of said mandrel, one rof said pins at one horizontal plane and twopins inla lower plane ,one directly below said one pin and theotherspacedvcircurnferentially 1243* therefrom. said pins being kadapted v to cooperate with a suitably shaped groove ona logging tool to align the logging elements thereofwith-said slots.

l2.` ln a logging sub adapted tobe inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, apair of O- ring seals mounted on said mandrel and sealinglyengaging the lower inner :surface ofsaidhousing when saidmandrel and said housing arc inv telescoped relation, releasable latch means adapted to maintainsaid mandrel and housing in telescoped relation,

-said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hook-shaped latch fingers pivotally mountedonsaid mandrel adjacent their mid-portions and adaptedto hook over said upwardly facing shoulder,.a`fsleeve slidably mounted for vertical lmovement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear againstthe upper inner surface of said latch fingers and maintain said fingers in latching relation when said sleeve is'in its uppermost lposition and to bear against the lower inner surfaceof said -latch fingers to rotate the latch fingers to release position when said sleeve moves downwardly, releasable lock4 fingers pivotally mounted on said mandrel belowsaid latchfingers, said lock fingers being adapted toholdsaid sleeve in its lowermost position to permit said housing to move downwardly past said latch fingers, said lovckfingers being adapted to be contacted byithedower end of said housing and rotated thereby to release said sleeve, for upward movement to relatch said latch fingers, .meansnorrnally urging said sleeve toward itsupperrnostposition, downwardly and inwardly tapered seat on the, upp e r. end of said sleeve adapted to receive a logging ltool dropped throughA the drilling string, a plurality of. longitudinally extending slots in said mandrel above saidlatch finger-s adapted to be uncovered to permit the ,pas sageof,logging, elements therethrough 4when said 9 Y mandrel and housing are in extended relation, and a plurality of radially inwardly extending aligning pins in the lower portion of said mandrel, one of said pins at one horizontal plane and two pins in a lower plane one directly below said one pin and the other spaced circumferentially 120 therefrom, said pins being adapted to cooperate with a suitably shaped groove on said logging tool to align the logging elements thereof with said slots.

13. In a logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, a pair of O-ring seals mounted on said mandrel and sealingly engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hook-shaped latch fingers pivotally mounted on said mandrel adjacent their mid-portions and adapted to hook over said upwardly facing shoulder, a sleeve slidablyk mounted for vertical movement from an upper to a lower position Within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch fingers and maintain said fingers in latching relationrwhen said sleeve is in its uppermost position and to bear against the lower inner surface of said latch ngers to rotate the latch fingers to release position when said sleeve moves downwardly, releasable lock fingers pivotally mounted on said mandrel below said latch lingers, said lock ngers being adapted to hold said sleeve in its lowermost position to permit said housing to move downwardly past said latch fingers, said lock fingers being adapted to be contacted by the lower end of said housing and rotated thereby to release said sleeve for upward movement to relatch said latch lingers, means normally urging said sleeve toward its uppermost position, a downwardly and inwardly tapered seat on the upper end of said sleeve adapted to receive a ylogging tool dropped through the drilling string, a plurality of longitudinally extending slots in said mandrel above said latch fingers adapted to be uncovered to permit the passage of logging elements therethrough when said mandrel and housing are in extended relation, a plurality of radially inwardly extending aligning pins inthe lower portion of said mandrel, one of said pins at one horizontal plane and two pins in a lower plane one directly below said one pin and the other spaced circumferentially 120 therefrom, said pins being adapted to cooperate with a suitably shaped groove on said logging tool to align the logging elements thereof with said slots, and means on the lower end of said housing adapted to interengage with means on said mandrel when said mandrel and housing are in telescoped relation to prevent relative rotation therebetween.

l14. Inv av logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, a pair of O-ring seals mounted on said mandrel and sealingly engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, va plurality of hook-shaped latch fingers pivotally mounted on said mandrel adjacent their mid-portions and adapted to hook over said upwardly facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch fingers and maintain said fingers in latching relation when said sleeve is in its uppermost position and to bear against the lower inner surface of said latch fingers to rotate the latch fingers to release position when said sleeve moves downwardly, releasable lock fingers pivotally mounted on said mandrel below f Y .'10 i I said latch nger's, said lock fingers being adapted to hold said sleeve in its lowermost position to permit said housing to move downwardly past said latch fingers, Vsaid lock fingers being adapted to be contacted by the lower end of said housing and rotated thereby to release said sleeve for upward movement to relatch said latch fingers, means normally urging said sleeve toward its uppermost position, a downwardly and inwardly tapered seat on the upper end of said sleeve adapted to receive a logging tool dropped through the drilling string, a plurality of longitudinally extending slots in said mandrel above said latch fingers adapted to be uncovered to permit the passage of logging elementsy therethrough when said mandrel and housing are in extended relation, a plurality of radially inwardly extending aligning pins in the lower portion of said mandrel, one of said pins at one horizontal plane and two pins in a lower plane one directly below said one pin and the other spaced circumferentially therefrom, said pins being adapted to cooperate with a suitably shaped groove on said logging tool to align the logging elements thereof with said slots, means on'the lower end of said housing adapted to interengage with means on said mandrel when said mandrel and housing are in telescoped relation to prevent relative rotation therebetween, a downwardly facing thrust bearing mounted on said mandrel adjacent the upper end thereof, said thrust bearing being adapted to abut said upwardly facing shoulder in said housing when said mandrel and housing are in extended relation.

l5. ln a logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing a pair of O-ring seals mounted on said mandrel and sealingly engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hook-shaped latch fingers pivotally mounted on said mandrel adjacent their mid-portions and adapted to hook over said upwardly facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch fingers and maintain said fingers in latching relation when said sleeve is in its uppermost position and to bear against the lower inner surface of said latch fingers to rotate the latch fingers to release position when said sleeve moves downwardly, a plurality of longitudinally extending slots in said mandrel above said latch fingers adapted to be uncovered to permit the passage of logging elements therethrough when said mandrel and housing are in extended relation, and a plurality of radially inwardly extending aligning pins in the lower portion of said mandrel, said pins being adapted to cooperate with a suitably shaped groove on a logging tool to align the logging elementsthereof with said slots.

16. ln a logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, a pair of O-ring seals mounted on said mandrel and sealingly engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hook-shaped latch fingers pivotally mounted on said mandrel adjacent their mid-portions and adapted to hook over said upwardly facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear again-st the upper inner surface of said latch fingers and maintain said fingers in latching relation when said sleeve is in its uppermost position and to bear against the lower inner surface of said latch fingers torotate the latch fingers to release position when sa'i'dsleeve moves'downwardly, a downwardly and inwardly"tapered4 seat on the'upper end of said sleeve adapted to receivela logging tool dropped through the drilling string, a Vplurality of longitudinally extending slots in said mandrel above said latch fingers adapted to be uncovered to permit the passage of logging elements therethrough when said mandrel and housing are in extended relation, and a plurality of radially inwardly extending aligning pins in the lower portion of said mandrel, said pins being adapted to cooperate with a suitably shaped groove on said logging tool to align the logging elements thereof with said slots.

17. In a logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, a pair of O-ring seals mounted on said mandrel and sealingly engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of hook-shaped latch ngers pivotally mounted on said mandrel adjacent their mid-portions and adapted to hook over said upwardly facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch lingers and maintain said lingers in latching relation when said sleeve is in its uppermost position and to bear against the lower inner surface of said latch lingers to rotate the latch fingers to release position when said sleeve moves downwardly, a plurality of longitudinally extending slots in said mandrel above said latch lingers adapted to be uncovered to permit the passage of logging elements therethrough when said mandrel and housing are in extended relation, and a plurality of radially inwardly extending aligning pins in the lower portion of said mandrel, one of said pins at one horizontal plane and two pins in a lower plane one directly below said one pin and the other spaced circumferentially 120 therefrom, -said pins being adapted to cooperate with a suitably shaped groove on a logging tool to align the logging elements thereof with said slots, interengaging means on said mandrel and housing adapted to prevent relative rotation therebetween when said mandrel and housing are in telescoped relation, and a downwardly facing thrust bearing adjacent the upper end of said mandrel adapted to abut the upwardly facing shoulder in said housing when said mandrel and housing are in extended relation.

18. In a logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, a pair of O-ring seals mounted on said mandrel and sealingly engaging the lower inner surface of said housing when said mandrel and said housing are in telescoped relation, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upward-,

ly facing internal shoulder in said housing, aplurality of hook-shapedlatch fingers pivotally-mounted Von said mandrel adjacent their mid-portions and adapted to hook over said upwardly facing shoulder, a sleeve slidably mounted for vertical movement from an upper to a lower position within said mandrel, an external boss on said sleeve adapted to bear against the upper inner surface of said latch fingers and maintain said fingers in latching relation when said sleeve is in its uppermost position and to 'near against the lower inner surface of said latch fingers to rotate the latch lingers to release position when said sleeve moves downwardly, a downwardly and inwardly tapered seat on the upper end of said sleeve adapted to receive a logging tool dropped through the drilling string, a plurality of longitudinally extending slots in said mandrel above said latch fingers adapted to be uncovered to permit the passage of logging elements therethrough when said mandrel and housing are in extended relation, and a plurality of radially inwardly extending aligning pins in the lower portion of said mandrel, one of said pins at one horizontal plane and two pins in a lower plane one directly below said one pinand the other spaced circumferentially therefrom, said pins being adapted to cooperate with a suitably shaped groovev on said logging tool to align the logging elements thereof with said slots, interengaging means on said mandrel and housing adapted to prevent relative rotation therebetween when said mandrel and housing are in telescoped relation, and a downwardly facing thrust bearing adjacent the upper end of said mandrel adapted to abut the upwardly facing shoulder in said housing when said mandrel and housing are in extended relation.

i9. In a logging sub adapted to be inserted in a drilling string, a housing, a tubular mandrel telescopically received in said housing, releasable latch means adapted to maintain said mandrel and housing in telescoped relation, said latch means comprising an upwardly facing internal shoulder in said housing, a plurality of latch fingers pivotally mounted on said mandrel adjacent their mid-portions and adapted at their upper ends to engage said upwardly facing shoulder in latching relation, a sleeve slidably mountedfor vertical movement from an upper to a lower position within said mandrel, and external means on said sleeve adapted to bear against the upper end portion of said latch fingers and maintain said lingers in latching relation with said shoulder when said sleeve is in its uppermost position and to engage the lower end portion of said latch lingers to pivot said fingers to release position when said sleeve moves downwardly. i

References Cited in the file of this patent UNITED STATES PATENTS 1,599,998 Heck Sept. 14, 1926 2,102,080 Kinley Dec. 12, 1937 2,468,849 Trainor May 3, 1949 2,621,745 Toelke Dec. 16, 1952-