US2532716A

US2532716A - Double tube core barrel for core drilling

Info

Publication number: US2532716A
Application number: US788427A
Authority: US
Inventors: Jesse L Havlick
Original assignee: GERBEN MEIDEMA
Current assignee: GERBEN MEIDEMA
Priority date: 1947-11-28
Filing date: 1947-11-28
Publication date: 1950-12-05
Anticipated expiration: 1967-12-05

Description

Dec. 5, 1950 J. L. HAVLICK Filed NOV. 28. 1947 F /'g. 2. F ig. /7

2 Sheets-Sheet 1 Fig.3.

4 Inventor A J Jesse L. Ha v/ic/r Mp/W 1950 J. L. HAVLICK 2,532,716

DOUBLE TUBE CORE BARREL FOR CORE DRILLING Filed NOV. 28. 1947 2 She'hS-Shmit 2 Inventor Jesse L. #0 v/ick By M9:

Patented Dec. 5, 1950 DOUBLE TUBE com: BARREL FOR CORE DRILLING forty per cent Wash.

Jesse L. Havlick, Spokane, Wash., assignor of to Gerben Meidema, Spokane,

Application November '28, 1947, Serial No. 788,427

' Claims (01. 255-72) M invention relates to improvements in doubletube core barrels for use in obtaining sample coresincore drilling operations.

E :The primary object of my invention is to achieve, especially in core drilling in soft formations, better core delivery to the collar of the hole than has heretofore been possible with core barrels of commerce. V

Another object is to provide improved means for. retaining the core in the bit and picking up the core closer to the bottom of the hole than has heretofore been possible.

Still another object is to seal .olf from the core, duringthe drilling operation, water circulating through the barrel to the bottom of the hole for drilling purposes;...

-..:Still.another objectv is to provide for discharging such water at the leading end of the bit to facilitate drilling;

Still another object to. provide, when the drilling period is ended, either by the barrel be issimple in construction, will not get out of order,

and .is comparatively inexpensive to manufacture and use.

. Other and subordinate objects, also, within the purview of. my invention, together with the precise nature of my improvements, will be readily understood when the succeeding description and claims are readwith reference to the drawings accompanying and forming part of this specification.

. In said drawings: Figure 1 is a view in side elevation, partly broken away, of my improved double tube core barrel in a preferred embodiment thereof; "Figure 2 is a view in longitudinal section, partly inside elevation, taken on the line 2-2 of Figure 1; 7

i Figure 3 is a fragmentary view in vertical section taken on the line 3-3 of Figure 2 and drawn toa larger scale; Q

Figure 4* Ba similar view taken on the line 4-4 of Figure 2;

""Figure 5 is a view in end elevation of the head section drawn to a larger scale;

IL'Figure 6 is a view in transverse section taken on the line 6-6 of Figure '3; 4 v k Figure 7 is a similar view taken. on line 'l-'l of Figure 4;

Figure 8 is another similar view taken 0 lined-J of Figu e 4;

. 2 Figure 9 is a view in side elevation of the core lifter drawn to a larger scale; and

Figure 10 is a view in plan of the core lifter.

Referring to the drawings by numerals, my im proved core barrel, as shown, comprises a cylindrical head section l with a lower reduced, externally threaded end 2. The head section I is formed. with the usual internally threaded upper sleeve portion 3 for connection to the usual hol-- low rotating drill stem, not shown. A lower end, axial bore 4 is provided in said head section I and an axial reduced water return bore leading from said bore 3 to the interior of the sleeve portion 3. Longitudinal water discharge ports 6 extend from the sleeve portion 3 to the lower end of said head section I and are grouped around the bores 4, 5 in downwardly flaring relation.

An outer core barrel section I is threaded at its upper end onto the lower end of said head section I for rotation therewith, and with a tubular shell section 8 threaded onto the lower end thereof of slightly smaller internal diameter than said core barrel section I and provided with longitudinal water passage grooves 9 therein.

A tubular diamond point core bit Hi, shown without the diamond points as sulficient for the present purposes, is threaded onto the lower end of the shell section 8. The drill bit H1 is provided with the usual downwardly tapered, intermediate bore portion ll which, in this instance, is spaced below the lower end of the shell section 8. Longitudinal water discharge ports l2 are provided in the drill bit, Ill extendin from the upper end of said bore portion ll tothe bottom, or leading face of said drill bit.

An inner, relatively smaller diameter core bar-' rel section I3 is yieldingly suspended, rotatably, in the outer core barrel section I from the head section. and in spaced relation to said outer core barrel section I to permit water to pass between said barrel sections, the suspension means comprising the following.

A guide bolt I4 with an upper end threaded into the bore 4 depends axially from the head section I with a lower end head it thereon and an axial water return bore [6 extending therethrough into communication with the water return bore 5.

An end thrust ball bearing assembly l'lsur rounding said bolt l4 rests on the head 15 and supports thereon a sleeve I8 surrounding said bolt M with a liner bushing l9, said sleeve l8 having the upper end of the inner core barrel section 13 suitably fixed thereto flush therewith.

A second ball bearing assembly Zllsurroundingsaid bolt 14 rests on a sealing washer 2! on top of the sleeve l8 and supports a cup-like sleeve 22 surrounding said bolt M with a sealing washerv 23 between the bottom of said sleeve and said assembly 20.

A coiled expansion spring 24 surrounds said bolt I4 and is interposed between the bottom of said sleeve 22' and a flanged collar 25 on the bolt I4 clamped against the lower end of the head section I by a shoulder 26 on said bolt I4. The purpose of the collar 25 will presently appear.

As will be apparent, the sleeve I8 with its liner I9, and the ball bearing assembly 20 and sleeve 22 are slidable upwardly on the guide bolt I l in opposition to the tension exerted by the coil spring 24 to permit yielding upward movement of the inner core barrel section I3 in the outer core barrel section 1, and said sleeves I3, 22, together with the washers 2|, 23 and said assembly 29, are spaced from the outer core barrel section 1 for the same purpose as the inner core barrel s6;- tion I3. Due to the described arrangement, the outer and inner core barrel sections 1, I3 are varranged for relative advance and retraction endwise. As best shown in Figure 4, in the normal downward, or advance, limit of movement of the inner core barrel section I3, as determined by the head I of the guide bolt I4, in a manner which will be clear, the lower end of the inner core barrel section I3 is disposed in the bit It! below the lower end of the shell section 8 but above the tapered bore portion I I in said bit.

A core lifter 21 is attached to the lower end of the inner core barrel section IS, in the downward limit of movement of said core barrel section, in

the outer core barrel section 1, to extend downwardly into the tapered bore II part way. The core lifter 21 has the form of a tubular, longitudinally split body 28 of the same internal'diameter as that of said inner core barrel I3, when ate tached, said body being formed of resilient mate-. rial whereby the same tends to contract circumferentially into reduced size diametrically. Longitudinal, laterally spaced ribs 29 on said body 21, of flat form, extend above the upper end thereof to form gripping fingers 39 for clamping engagement with the periphery of the lower end of said inner core section IS in the space between the lower end of said shell section 8 and said bore portion II. Shoulders 3| on the fingers 3B fiush with the upper edge of the body 28 seat the lower end of the inner core barrel section I3 with its inner circumferential wall flush with the corresponding wall of said body 28. The ribs 29 taper downwardly from the fingers 30 to fit said bore portion I I and to a lower end feather edge 32 on said body 28 fitting in said bore portion II so as to obviate forming a shoulder therein.

As will be understood, the described core lifter 21 when clamped to the lower end of the inner core barrel section I3, as described, is held by said barrel section in an expanded position. I n this connection, the edges 33 of the split in the body 28are beveled to overlap, as shown in Figure 10, in the expanded condition of the core lifter 2 I and so as to obviate an internal shoulder in said body 23 when said lifter is either expanded or contracted. 7 An annular, flat, check valve member 34 is-slidably mounted on the collar 25 for engagement with the upper end of the sleeve 22 to be slid thereby upwardly against the lower end of the head section I in covering relation to the lower ends of the water discharge ports 6, to thereby close said ports. The valve member 34, when re leased, slides downwardly on said collar 25, under the influence of gravity, into port-opening position.

Suitable hard

metal ware sleeves

35, 36 are 4 provided on the head section I and the outer barrel section 1 where desirable.

Referring now to the operatiQll 0f the described invention ,the core, not shown, passes upwardly through the bit I0 into the inner barrel section I3 freely, without any spring pressure being exerted against the same by the core lifter 21, the body 28 of said lifter acting as a guide for the core and as a guard to protect the lower end of the inner core barrel section against wear. The core lifter 21, when expanded, substantially seals off the core, during the drilling period, from the water circulating through the barrel. In my improved core barrel, the water passes downwardly from the head section I through the discharge p rt 6, the pace bet e the out r and nne core barrel sections 1, I3, the grooves 9 in the. shell section 8, and the discharge ports I2 in the bit I0 and discharges at the iace or leading end of said bit to return through the bit ,I 0, core lifter 21, inner core barrel section I3 and the return port I6 to the head section I, which is to say the. upper sleeve portion 3 thereof.

When the drilling period is ended, either by the inner core barrel section I3 being filled with core, or by the core blocking or wedging in said sec-: tion, the inner core barrel section I3. will remain stationary while the outer core barrel section 1 continues to rotate with the bit I0 and to advance relative to said inner core barrel section I3. This advance of the outer core barrel section .1 causes the lower end of the shellsection 8 to engage the fingers 3t and thereby push the core lifter 21 off the lower end of the inner core barrel section [3, at which point said core lifter ,21 contracts about the core to yieldingly grip the same. Such ad- Vance of the outer core barrel section 1 also causes the check valve member 34 to be engaged with the upper end of the sleeve .22 and thereby moved upwardly to close the discharge ports vIi and block the circulation of water through the barrel. This will cause a drill operator at the surface to notice a change in pressure on the pressure gauge, not shown, of the usual water circulating pump, not shown, at the surface, whereby the drilling operator will be advised that the barrel should be lifted out of the hole, not shown, being drilled in. As soon as the drill operator starts to lift the barrel from the bottom of the hole, the core lifter 21 is forced down in the bit III by ad Vance of the inner core barrel section I3 relative to the outer core barrel section 1, such advance of the inner core barrel sections I3 being caused by the coil spring 24 previously compressed by the described advance of the outer core barrel section 1 relative to the inner core barrel section. This forcing of the core lifter 21 down in the bit Ii] results in the tapered bore portion II incoaction with the ribs 29 forcing said core lifter into further contracted position about the core, thus insuring retaining of the core in the bit and picking up of the core close to the bottom of the hole.

The foregoing will, it is believed, suffice to impart a clearunderstanding of my invention, without further explanation. V

Manifestly,ethe invention, as described, is susceptible of modification without departing rm the inventive concept, and right is herein reserved to such modifications as fall within the scope of the appended claims.

Having described the invention, what is claimed as new is:

1. A core barrel comprising a head section- 'for thereby, an outer core barrel section fixed to and depending from said head section for rotation therewith, a tubular drill bit depending from the lower end or" the outer core barrel section and fixed thereto for drilling a core, an inner core barrel section for receiving said core, means to mount the inner core barrel section on said head section to provide for relative endwise advance and retraction of said outer and inner core barrel sections comprising a bolt depending axially from head section, and a sleeve fixed to the upper end of the inner core barrel section and slidable and rotatable on said bolt, and an annular core lifter slidably fitted on the lower end of the inner core barrel section and in said bit for sliding oil end and being engageable by the lower end of the outer core barrel section to be thrust downwardly oil the inner core barrel section upon advance of said outer section relative to said inner section, said lifter being resilient for contraction in suiiicient degree to grip the core in said bit when said lifter is thrust off the inner core barrel section.

2. A core barrel comprising a head section for attachment to a hollow drill stem to be rotated thereby, an outer core barrel section fixed to and depending from said head section for rotation therewith, a tubular drill bit depending from the lower end of the outer core barrel section and fixed thereto for drilling a core, an inner core barrel section for receiving said core, means to mount the inner core barrel section on said head section to providefor relative endwise advance and retraction of said outer and inner core barrel sections comprising a bolt depending axially from said head section, and a sleeve fixed to the upper end of the inner core barrel section and slidable and rotatable on said bolt, an annular core lifter slidably fitted on the lower end of the inner core barrel section and in said bit for sliding off said end and being engageable by the lower end of the outer core barrel section to be thrust downwardly off the inner core barrel section upon advance of said outer section relative to said inner section, said lifter being resilient for contraction in sufiicient degree to grip the core in said bit when said lifter is thrust off the inner core barrel section, and camming devices on said lifter and bit coacting during downward thrust of said lifter to further contract the same and tighten the grip thereof on said core.

3. A core barrel comprising a head section for attachment to a hollow drill stem to be rotated thereby. an outer core barrel section fixed thereto and depending from said head section for rotation therewith, a tubular drill bit depending from the lower end of the outer core barrel section and fixed thereto for drilling a core, an inner core barrel section for receiving the core, means to mount the inner core barrel section on said head section to provide for relative endwise advance and retraction of said outer and inner core barrel sections comprising a bolt depending axially from said head section, and a sleeve fixed to the upper end of the inner core barrel section and slidable and rotatable on said barrel, said head section being ported and said inner and outer core barrel sections being spaced apart for passing water to said bit. and valve means operated by advance of the outer core barrel section relative to the inner core barrel section to close said ports and block passage of water to said bit.

4. A core barrel comprising a head section for attachment to a hollow drill stem to be rotated thereby, an outer core barrel section fixed to and depending from said head section for rotation therewith, a tubular drill bit depending from the lower end of the outer core barrel section for receiving said core, means to mount the inner core barrel section on said head section to provide for relative endwise advance and retraction of said outer and inner core barrel sections comprising a bolt depending axially from said head section, and a sleeve fixed to the upper end of the inner core barrel section and. slidable and rotatable on said bolt, an annular core lifter slidably fitted on the lower end of the inner core barrel section and in said bit for sliding ofi said end and being engageable by the lower end of the outer core barrel section to be thrust downwardly oif the inner core barrel section upon advance of said outer section relative to said inner section, said lifter being resilient for contraction in sufficient degree to grip the core in said bit when said lifter is thrust oiT the inner core barrel section, and camming devices on said lifter and bit coacting during downward thrust of said lifter to further contract the same and tighten the grip thereof on said core comprising downwardly converging ribs on said lifter, and a downwardly tapered bore portion in said bit.

5. A core barrel comprising a head section for attachment to a hollow drill stem to be rotated thereby, an outer core barrel section fixed thereto and depending from said head section for rotation therewith, a tubular drill bit depending from the lower end of the outer core barrel section and fixed thereto for drilling a core, an inner core barrel section for receiving the core, means to mount the inner core barrel section on said head section to provide for relative endwise advance and retraction of said outer and inner core barrel sections comprising a bolt depending axially from said head section, and a sleeve fixed to the up er end of the inner core barrel section and slidable and rotatable on said barrel said head section being ported and said inner and outer core barrel sections being spaced apart for passing water to said bit. and valve means opera ed by advance of the outer core barrel section relative to the inner core barrel section to close said ports and block passage of water to said hit comprising an annular valve member circumscribing said bolt and mova le relative thereto to clo e said ports, and a member on said bolt for moving the valve member when said outer core barrel is advanced relative to said inner core barrel.

JESSE L. I-IAVLICK.

REFERENCES CITED The fol owin references are of record in the file of this patent:

UNILi ED STATES PATENTS Num er Name Date Re.1 45 Baker Apr. 14, 1931 1,611,504 Baker Dec. 21, 1926 1.253 581 Schmissrauter et al. Apr. 12, 1932' 1.903.232 Giesey Mar. 28, 1933 1994.848 Baker et al Mar. 19, 1935 2.001.764 Bradley May 21, 1935 2,040.899 Whinnen May 19, 1936 2.260 6'78 Muhlbach Oct. 28, 1941 2,422,955 Duffield June 2 1, 1947 FOREIGN PATENTS Number Country Date 5.300 Great Britain 1914 608,248 Germany Jan. 18, 1935