US3658298A - Drilling rig with shiftable crown blocks - Google Patents

Drilling rig with shiftable crown blocks Download PDF

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Publication number
US3658298A
US3658298A US3658298DA US3658298A US 3658298 A US3658298 A US 3658298A US 3658298D A US3658298D A US 3658298DA US 3658298 A US3658298 A US 3658298A
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Prior art keywords
blocks
crown
guides
derrick
traveling
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Expired - Lifetime
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Wesley W Moore
Fletcher H Redwine
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NATIONAL-OILWELL A CORP OF
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United States Steel Corp
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    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B15/00Derricks; Masts; Other supports

Abstract

A drilling rig equipped with two sets of hoisting mechanisms. The two crown blocks are shiftable to enable either block to be positioned over the drill hole. The crown blocks carry depending guides for the two traveling blocks. The guides move horizontally and vertically as the crown blocks are shifted, but are constrained to remain vertical.

Description

United States Patent Moore et al.

[54] DRILLING RIG WITH SHIFTABLE CROWN BLOCKS [72] Inventors: Wesley W. Moore, Dallas; Fletcher H. v Redwine, Irving, both of Tex.

{ 73] Assignee: United States Steel Corporation [22] Filed: Oct. 14, 1969 211 Appl. No.: 866,259

521 u.s.c| ..2s4/190,214/2.5 [51] lnt.Cl ..B66dl/36 5s FieldofSearch ..254/l90,l90B,[92;214/2,

[56] References Cited UNITED STATES PATENTS 2,187,392 1/1940 Chappell ..254/l9OB Apr. 25, 1972 2,643,005 6/1953 DeJarnett ..2l4/2.5 2,685,378 8/1954 Stone ..2l4/2.5

3,336,003 8/1967 Crooke eta]. ..254/l90 Primary ExaminerEvon C. Blunk Assistant Examiner-Merle F. Maffei Attorney-Walter P. Wood [5 7] ABSTRACT A drilling rig equipped with two sets of hoisting mechanisms. The two crown blocks are shiftable to enable either block to be positioned over the drill hole. The crown blocks carry depending guides for the two traveling blocks. The guides move horizontally and vertically as the crown blocks are shifted, but are constrained to remain vertical.

7 Claims, 8 Drawing Figures PATENTED APR 2 5 1972 3.658298 SHEET 2 OF 4 E I w v N -9 I I w m h I I a I w .R l

lNl/BVTORS WESLEY W MOORE 8 FLETCHER H. REDWl/VE A Home PATENTED APR 2 5 I972 SHEET 4 0F 4 FIG: 7

INVENTORS WESLEY W MOORE a FLETCHER H. REDW/IVE y Am /4/% -&

A Homer with a single derrick. This arrangement hasthe advantage of enabling a drilling crew to carry on two operations simultaneously. For example, when the drill string is pulled from the hole, one hoisting mechanism can be used to rack a stand of drill pipe, while the other is raising the next stand. The arrangement requires a crown block assembly which enables the two blocks to be shifted back and forth horizontally so that either can be positioned over the drill hole while the other is positioned at one side. Reference can be made to Chappell U. S. Pat. No. 2,187,392, for an exemplary showing ofa rig of this type, and a more detailed explanation of its operation and advantages.

An object of our invention is to provide an improved crownblock assembly for a drilling rig of the foregoing type, which assembly is formed as a unit freely movable on antifriction bearings for positioning either of the two crown blocks over the drill hole.

A further object is to provide a crown-block assembly of the foregoing type in which the unit carries depending guides for two traveling blocks under the respective crown blocks, whereby the traveling blocks and their guides shift uniformly with the crown blocks in a constrained path without swaying or colliding.

In the drawings:

FIG. I is a diagrammatic side elevational view of a derrick equipped with our improved crown-block assembly and traveling-block guides, the crown and traveling blocks at the left being positioned over the drill hole;

FIG. 2 is similar view, but with the blocks at the right positioned over the drill hole;

FIG. 3 is a top plan view of the crown-block assembly with the block at the right removed;

FIG. 4 is a vertical section on line IV -IV of FIG. 3;

FIG. 5 is a vertical section on line V-V of FIG. 3;

FIG. 6 is a side elevational view of one traveling block and the traveling-block guides;

FIG. 7 is a horizontal section on line VIIVII of FIG.'6; and

FIG. 8 is a diagrammatic side elevational view showing how the guides are connected to move with the crown blocks.

FIGS. 1 and 2 show diagrammatically a drillingplatform 10 which supports a derrick 12 and a rotary table 13. The rig is equipped with two sets of hoisting mechanisms. The set at the left includes a drawworks 14, a crown block 15, a traveling block 16, a drilling cable 17, and an elevator:18. Theset atthe right includes similar parts 14a, 15a, 16a, 17a andlSa respectively. Except as hereinafter pointed out, these partsper se can be of conventional construction and hence are not shown in detail. The crown blocks 15 and 15a are shiftable horizontally so that either may be positioned over the rotary table 13 and the drill hole beneath. FIG. 1 shows the left crown block 15 positioned over the rotary table 13, and the elevator 18 connected to a stand 19 of drill pipe coming out of the drill hole. The right crown block 150 is shown positioned to the right of the rotary table, and the elevator 18a loweredin readiness to engage the next stand. A stand 19a has been racked at the right side of the derrick 12. FIG. 2 shows the right crown block 15a positioned over the rotary table, andthe elevator 18a connected to the next'stand. Crownblock I5 is shown positioned to the left of the rotary table to rack the stand l9'at the left side of the derrick.

As best shown in FIGS. 3,4 and 5, derrick 12 includes horizontal water table beams 22 and transverse beams 23 and 23a at its upper end. The upper flanges of beams 22 carry respective linear roller bearings, each of which includes a lower race 24, rollers 25 and an upper race 26(FIG. 5). The

I crown blocks 15 and 15a include transverse basemembers 27 fixed across the upper races 26. Preferably we form the upper races of two sections connected end-to-end: with bolts 28 to enable either crown block and the corresponding upper race sections to be removed without disturbing the other. The crown blocks also include the usual guide sheaves29 and multiple sheaves 30, which are journaled in suitable bearings and around which the cables 17 and 17a are reeved.

We attach carriers 32 and 32a to the undersides of the base members 27 of the respective crown blocks 15 and 15a. A double-acting movable hydraulic cylinder 33 extends through the twocarriers and is attached thereto (FIG. 4). We attach hollow stationary piston rods 34 and 34a to the transverse beams 23 and 23a. The piston rods extend into opposite ends of cylinder 33 through stuffing boxes 35 and 35a. The ends of the piston rods within the cylinder carry pistons 36 and 36a. Each piston rod has a port adjacent its end communicating with the portion of the cylinder between the piston and stuffing box for admitting or discharging hydraulic fluid. We connect the outer ends of the piston rods to suitable sources of hydraulic fluid, not shown. When we admit fluid to cylinder 33 through piston rod 34, the crown blocks 15 and 15a shift toward the left from the position shown in FIG. 1 to the position shown in FIG. 2. When we admit fluid through the piston rod 34a, the crown blocks shift the other way. It is apparent we could use other means for shifting the crown blocks, such as a screw or a rack and pinion.

We journal left and right pairs of sprockets 38 and 38a to the outboard ends of carriers 32 and 32a respectively. We attach a pair of longitudinally extending straps 39 between the transverse beams 23 and 23a. We anchor respective left and right pairs of chains 41 and 41a (four altogether) to the undersides of straps 39 and run these chains over the corresponding sprockets 38 and 38a as shown diagrammatically in FIG. 8. We connect the depending ends of the two pairs of chains 41 and 41a to the upper ends of left and right guides 43 and 43a for the traveling blocks 16 and respectively. We pivot a plurality of links 44 to the frame of derrick l2 and to each guide 43 and 43a, as best shown in the diagrammatic views of FIGS. 1 and 2. When the crown-block assembly shifts in either direction, the sprockets 38 and 38a of course shift with it, but the upper ends of chains 41 and 41a are anchored to the stationary straps 39. Consequently guides 43 and 43a move both horizontally and vertically through distances equal to the distance through which the crown-block assembly moves, in accordance with well known principles of pulley mechanisms. As the guides move, the links 44 constrain their motion so that they always remain vertical.

As best shown in FIGS. 6 and 7, guide 43 includes a pair of vertically extending rails 45, preferably in the form of H- beams, and cross bars 46 connecting the rails. The links 44 preferably are double and are pivoted to the corner members of the derrick and to the cross bars 46. A carriage 47 is attached to the side face of the traveling block 16. Rollers 48 are journaled to carriage 47 and ride on inner faces of the flanges of rails 45as the traveling block moves up and down. Thus the guide assures that the traveling block always moves in a truly vertical path and does not sway to either side. The guide 43a is of similar construction; hence we have not shown it in detail.

From the foregoing description it is seen that our invention affordsa simple effective mechanism for shifting a pair of crown blocks back and forth as needed in a rig equipped with two hoisting mechanisms. The traveling blocks are movable alongguideswhich shift with the crown blocks and are constrained to remain always vertical. Thus the traveling blocks cannot sway or collide.

We claim:

1. In awell-drilling rig which is equipped with two sets of hoisting mechanisms used with a single derrick, said mechanisms including two crown blocks supported at the top of the derrick, means operatively connected with said blocks for shifting them horizontally with respect to the derrick, two traveling blocks, and drilling cables suspending said traveling blocks from the respective crown blocks, the combination therewithof:

respective vertically extending guides beneath said crown blocks; l 1

means connecting said guides with said crown blocks for shifting said guides uniformly horizontally and vertically as said crown blocks shift horizontally;

means connected to said guides and said derrick below said crown blocks constraining said guides to remain vertical as they shift;

and means connected to said traveling blocks and riding on the respective guides, whereby the traveling blocks always move in vertical paths as they are raised or lowered without swaying.

2. A combination as defined in claim 1 in which said crown blocks form part of an assembly which includes shiftable carriers and rotatable elements journaled to the respective carriers, and in which the means connecting said guides with said crown blocks includes flexible members anchored at one of their ends to the top of said derrick, running over the respective rotatable elements; and anchored at their opposite ends to said guides, whereby said guides move equal distances horizontally and vertically as said crown blocks are shifted horizontally.

3. A combination as defined in claim 1 in which the means constraining said guides to remain vertical include a plurality of links pivoted to said derrick and to said guides.

4. In a well drilling rig which is equipped with two sets of hoisting mechanisms used with a single derrick, said mechanisms including two crown blocks supported at the top of the derrick, means operatively connected with said blocks for shifting them horizontally with respect to the derrick, two traveling blocks, and drilling cables suspending said traveling blocks from the respective crown blocks, said crown blocks being part of an assembly which comprises:

a pair of linear roller bearings, each of which includes-a respective lower race fixed to the top of the derrick, rollers riding in said lower race, and a respective upper race riding on said rollers;

base members on said crown blocks fixed across said upper races;

respective carriers fixed to the undersides of said base members;

sprockets joumaled to each of said carriers; and

power means connected to said carriers for shifting said crown blocks horizontally as a unit;

said rig also including;

chains having one end anchored with respect to the top of the derrick and running over said sprockets; and

a pair of guides for said traveling blocks depending from said chains and movable uniformly horizontally and vertically as said crown blocks are shifted.

5. An assembly as defined in claim 4 comprising in addition links pivoted to said guides and to the derrick constraining the guides to a vertical position as they move.

6. An assembly as defined in claim 4 in which the upper races are of sectional construction bolted end-to-end to enable either crown block and its upper races and carrier to be removed without disturbing the other.

7. An assembly as defined in claim 4 in which said power means includes a movable fluid-pressure cylinder extending through said carriers and attached thereto, hollow piston rods fixed to the top of the derrick and extending into each end of said cylinder, and pistons on said piston rods within said cylinder.

Claims (7)

1. In a well-drilling rig which is equipped with two sets of hoisting mechanisms used with a single derrick, said mechanisms including two crown blocks supported at the top of the derrick, means operatively connected with said blocks for shifting them horizontally with respect to the derrick, two traveling blocks, and drilling cables suspending said traveling blocks from the respective crown blocks, the combination therewith of: respective vertically extending guides beneath said crown blocks; means connecting said guides with said crown blocks for shifting said guides uniformly horizontally and vertically as said crown blocks shift horizontally; means connected to said guides and said derrick below said crown blocks constraining said guides to remain vertical as they shift; and means connected to said traveling blocks and riding on the respective guides, whereby the traveling blocks always move in vertical paths as they are raised or lowered without swaying.
2. A combination as defined in claim 1 in which said crown blocks form part of an assembly which includes shiftable carriers and rotatable elements journaled to the respective carriers, and in which the means connecting said guides with said crown blocks includes flexible members anchored at one of their ends to the top of said derrick, running over the respective rotatable elements; and anchored at their opposite ends to said guides, whereby said guides move equal distances horizontally and vertically as said crown blocks are shifted horizontally.
3. A combination as defined in claim 1 in which the means constraining said guides to remain vertical include a plurality of links pivoted to said derrick and to said guides.
4. In a well drilling rig which is equipped with two sets of hoisting mechanisms used with a single derrick, said mechanisms including two crown blocks supported at the top of the derrick, means operatively connected with said blocks for shifting them horizontally with respect to the derrick, two traveling blocks, and drilling cables suspending said traveling blocks from the respective crown blocks, said crown blocks being part of an assembly which comprises: a pair of linear roller bearings, each of which includes a respective lower race fixed to the top of the derrick, rollers riding in said lower race, and a respective upper race riding on said rollers; base members on said crown blocks fixed across said upper races; respective carriers fixed to the undersides of said base members; sprockets journaled to each of said carriers; and power means connected to said carriers for shifting said crown blocks horizontally as a unit; said rig also including; chains having one end anchored with respect to the top of the derrick and running over said sprockets; and a pair of guides for said traveling blocks depending from said chains and movable uniformly horizontally and vertically as said crown blocks are shifted.
5. An aSsembly as defined in claim 4 comprising in addition links pivoted to said guides and to the derrick constraining the guides to a vertical position as they move.
6. An assembly as defined in claim 4 in which the upper races are of sectional construction bolted end-to-end to enable either crown block and its upper races and carrier to be removed without disturbing the other.
7. An assembly as defined in claim 4 in which said power means includes a movable fluid-pressure cylinder extending through said carriers and attached thereto, hollow piston rods fixed to the top of the derrick and extending into each end of said cylinder, and pistons on said piston rods within said cylinder.
US3658298A 1969-10-14 1969-10-14 Drilling rig with shiftable crown blocks Expired - Lifetime US3658298A (en)

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JP (1) JPS4942563B1 (en)
CA (1) CA926852A (en)
DE (1) DE2049539B2 (en)
FR (1) FR2064321B1 (en)
GB (1) GB1327782A (en)

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3936034A (en) * 1974-04-08 1976-02-03 Vetco Offshore Industries, Inc. Balanced hoist apparatus
US4208158A (en) * 1978-04-10 1980-06-17 Franklin Enterprises, Inc. Auxiliary offshore rig and methods for using same
US4796863A (en) * 1986-10-23 1989-01-10 Parco Mast And Substructures, Inc. Dual cluster crown block
US4836300A (en) * 1986-10-23 1989-06-06 Parco Mast And Substructures, Inc. Method of performing drilling operations from a derrick
US4842250A (en) * 1987-09-03 1989-06-27 W-N Apache Corporation Line reeving system for earth drilling machine
US5244329A (en) * 1989-05-12 1993-09-14 Hitec A.S. Arrangement in a pipe handling system
WO2001057355A1 (en) * 2000-02-03 2001-08-09 Precision Drilling Corporation Linear coiled tubing injector/hybrid sectional and coiled tubing drilling rig
US20030111232A1 (en) * 2001-12-17 2003-06-19 Welsh Walter Thomas Crown block shifting apparatus and method
US6595494B1 (en) * 1999-10-19 2003-07-22 Huisman Special Lifting Equipment B.V. Hoisting device, with compensator built into hoisting cable system
US20040089215A1 (en) * 2002-08-30 2004-05-13 Joop Roodenburg Multipurpose tower for monohull
US20040151549A1 (en) * 2002-10-17 2004-08-05 Joop Roodenburg Cantilevered multi purpose tower
US6868902B1 (en) 2002-01-14 2005-03-22 Itrec B.V. Multipurpose reeled tubing assembly
US6901998B1 (en) 2003-03-17 2005-06-07 Itrec B.V. Method for using a multipurpose system
US6926260B1 (en) 2001-07-02 2005-08-09 Itrec B.V. Compensation and hoisting apparatus
US6932553B1 (en) 2003-03-17 2005-08-23 Itrec, B.V. Multipurpose unit for drilling and well intervention
US6966106B1 (en) 2002-01-14 2005-11-22 Itrec B.V. Method and apparatus for transporting and running tubulars
EP1925549A2 (en) * 1996-05-03 2008-05-28 Transocean Offshore Deepwater Drilling Inc. Drillship or semi-submersible and multi-activity drilling assembly
US20100294568A1 (en) * 2006-06-19 2010-11-25 Paal Taraldrud Drawworks device on a drill floor
WO2011106311A1 (en) * 2010-02-24 2011-09-01 Devin International, Inc. Coiled tubing inline motion eliminator apparatus and method
US20120181084A1 (en) * 2010-11-19 2012-07-19 Rick Pilgrim System and Methods for Continuous and Near Continuous Drilling
DK201470227A1 (en) * 2014-04-16 2015-08-31 Maersk Drilling As An offshore drilling rig and a method of operating the same
US9677345B2 (en) 2015-05-27 2017-06-13 National Oilwell Varco, L.P. Well intervention apparatus and method

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DK517285D0 (en) * 1985-11-08 1985-11-08 Dansk Ind Syndikat The method and the drilling rig for drilling boreholes

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2187392A (en) * 1937-01-11 1940-01-16 Alvin H Lane Derrick
US2643005A (en) * 1948-03-12 1953-06-23 Paul A Medearis Well pipe handling equipment
US2685378A (en) * 1949-08-25 1954-08-03 Standard Oil Dev Co Method for handling drill pipe
US3336003A (en) * 1966-02-17 1967-08-15 Global Marine Inc Travelling block guide

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2187392A (en) * 1937-01-11 1940-01-16 Alvin H Lane Derrick
US2643005A (en) * 1948-03-12 1953-06-23 Paul A Medearis Well pipe handling equipment
US2685378A (en) * 1949-08-25 1954-08-03 Standard Oil Dev Co Method for handling drill pipe
US3336003A (en) * 1966-02-17 1967-08-15 Global Marine Inc Travelling block guide

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3936034A (en) * 1974-04-08 1976-02-03 Vetco Offshore Industries, Inc. Balanced hoist apparatus
US4208158A (en) * 1978-04-10 1980-06-17 Franklin Enterprises, Inc. Auxiliary offshore rig and methods for using same
US4796863A (en) * 1986-10-23 1989-01-10 Parco Mast And Substructures, Inc. Dual cluster crown block
US4836300A (en) * 1986-10-23 1989-06-06 Parco Mast And Substructures, Inc. Method of performing drilling operations from a derrick
US4842250A (en) * 1987-09-03 1989-06-27 W-N Apache Corporation Line reeving system for earth drilling machine
US5437527A (en) * 1989-05-12 1995-08-01 Hitech A/S Arrangement in a pipe handling system
US5244329A (en) * 1989-05-12 1993-09-14 Hitec A.S. Arrangement in a pipe handling system
EP1925549A3 (en) * 1996-05-03 2010-09-08 Transocean Offshore Deepwater Drilling Inc. Drillship or semi-submersible and multi-activity drilling assembly
EP1925549A2 (en) * 1996-05-03 2008-05-28 Transocean Offshore Deepwater Drilling Inc. Drillship or semi-submersible and multi-activity drilling assembly
EP2332822A3 (en) * 1996-05-03 2012-03-07 Transocean Offshore Deepwater Drilling Inc. Drillship or semi-submersible and multi-activity drilling assembly
US6595494B1 (en) * 1999-10-19 2003-07-22 Huisman Special Lifting Equipment B.V. Hoisting device, with compensator built into hoisting cable system
WO2001057355A1 (en) * 2000-02-03 2001-08-09 Precision Drilling Corporation Linear coiled tubing injector/hybrid sectional and coiled tubing drilling rig
US6408955B2 (en) 2000-02-03 2002-06-25 Precision Drilling Corporation Hybrid sectional and coiled tubing drilling rig
US6926103B1 (en) 2001-07-02 2005-08-09 Itrec B.V. Splittable block on a derrick
US6926260B1 (en) 2001-07-02 2005-08-09 Itrec B.V. Compensation and hoisting apparatus
US20030111232A1 (en) * 2001-12-17 2003-06-19 Welsh Walter Thomas Crown block shifting apparatus and method
US6868902B1 (en) 2002-01-14 2005-03-22 Itrec B.V. Multipurpose reeled tubing assembly
US6966106B1 (en) 2002-01-14 2005-11-22 Itrec B.V. Method and apparatus for transporting and running tubulars
US20050051072A1 (en) * 2002-08-30 2005-03-10 Joop Roodenburg Multipurpose tower for monohull with moveable hatch
US6871609B2 (en) 2002-08-30 2005-03-29 Itrec B.V. Multipurpose tower for monohull
US6988459B2 (en) 2002-08-30 2006-01-24 Itrec B.V. Multipurpose tower for monohull with moveable hatch
US20040089215A1 (en) * 2002-08-30 2004-05-13 Joop Roodenburg Multipurpose tower for monohull
US7083004B2 (en) 2002-10-17 2006-08-01 Itrec B.V. Cantilevered multi purpose tower and method for installing drilling equipment
US20040151549A1 (en) * 2002-10-17 2004-08-05 Joop Roodenburg Cantilevered multi purpose tower
US6901998B1 (en) 2003-03-17 2005-06-07 Itrec B.V. Method for using a multipurpose system
US6932553B1 (en) 2003-03-17 2005-08-23 Itrec, B.V. Multipurpose unit for drilling and well intervention
US8534387B2 (en) * 2006-06-19 2013-09-17 National Oilwell Norway As Drawworks device on a drill floor
US20100294568A1 (en) * 2006-06-19 2010-11-25 Paal Taraldrud Drawworks device on a drill floor
WO2011106311A1 (en) * 2010-02-24 2011-09-01 Devin International, Inc. Coiled tubing inline motion eliminator apparatus and method
US8672039B2 (en) 2010-02-24 2014-03-18 Devin International, Inc. Coiled tubing inline motion eliminator apparatus and method
US20120181084A1 (en) * 2010-11-19 2012-07-19 Rick Pilgrim System and Methods for Continuous and Near Continuous Drilling
US8955602B2 (en) * 2010-11-19 2015-02-17 Letourneau Technologies, Inc. System and methods for continuous and near continuous drilling
US9074455B2 (en) 2010-11-19 2015-07-07 Cameron Rig Solutions, Inc. Systems and methods for continuous and near continuous drilling
DK201470227A1 (en) * 2014-04-16 2015-08-31 Maersk Drilling As An offshore drilling rig and a method of operating the same
US9677345B2 (en) 2015-05-27 2017-06-13 National Oilwell Varco, L.P. Well intervention apparatus and method

Also Published As

Publication number Publication date Type
JPS4942563B1 (en) 1974-11-15 grant
GB1327782A (en) 1973-08-22 application
FR2064321B1 (en) 1975-03-14 grant
CA926852A1 (en) grant
DE2049539A1 (en) 1971-04-22 application
FR2064321A1 (en) 1971-07-23 application
CA926852A (en) 1973-05-22 grant
DE2049539B2 (en) 1977-05-18 application

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