US3336003A

US3336003A - Travelling block guide

Info

Publication number: US3336003A
Application number: US528262A
Authority: US
Inventors: Crooke Robert Curtis; Mar Corona Del; Knorr Gordon Dayton
Original assignee: Global Marine Inc
Current assignee: Global Marine Inc
Priority date: 1966-02-17
Filing date: 1966-02-17
Publication date: 1967-08-15
Anticipated expiration: 1984-08-15

Description

Aug. 15, 1967 R. c. cRooKE ETAL 3,336,003

TRAVELLING BLOCK GUIDE Filed Feb. 17, l96 6 4 Sheets-SheeJf I g- 15, 1967 R. c. cRooKE ETAL 3,336,003

TRAVELLING BLocx GUIDE Filed Feb. 17', 1966 4 Sheets-Sheet i' MMM Aug. 15, 1%7 R. c. cRooKE ETAL TRAVELLING BLOCK GUIDE 4 Sheets-Sheet Filed Feb. 17, 1966 MJ ffl f Www am 5M m WWW MW wy f z fa Aug- 15, I967 R. c. cRooKETAL 3,336,003

TRAVLLING BLocK GUIDE Filed Feb. 17, 1966 4 ASIetS-Sheet 4 United States Patent Ofiice 3336,003 Patented Aug. 15, 1967 fornia Filed Feb. 17, 1966, Ser. No. 528,262 8 Claims. (Cl. 254-190) ABSTRACT OF THE DISCLOSURE A guide for a travelling block in the derrick of a drilling n'g including guides defining a desired path of travel of the block vertically in the derrick, and block pivot means connected between the block and the guides mounting the block for pivotal m-ovement about two axes normal to the desired path of block travel.

This invention relates to apparatus for guiding a travelling block along a selected path in a derrick of an oil well drilling rig, for example, while constraining the travelling block from movement bodily laterally of such path.

Floating vessels are now being used with increasing frequency as a part of a Worldwide search for s'ubmarine oil reserves. In such vessels, a conventional oil well drilling rig, including a derrick fitted with a crown block and a travelling block, is provided for raising and lowering drill pipe and casing pipe through a rotary table located on the fioor of the rig. The rig is located over the main deck of the vessel above a central Well in the ship through which drilling Operations are performed. Because such vessels must operate in water having a depth of, in some cases, several thousand feet, the derrick structure including the travelling block must be massive in order to support the weight of a string of drill pipe several thousand feet in length.

Floating drilling vessels are subjected to many adverse conditions during their working life. Particularly troublesome are wave and wind induced heaving, rolling and pitching motions. If such a vessel is rolling considerably during a drilling operation, the travelling block is induced to swing laterally of a straight line between the center of the rotary table and the derrick crown block along which the block moves in response to operation of a cable drawworks provided as a part of the'rig. Such motion of the travelling block may result in a length of drill pipe being bent as it passes through the table during the process of running a drilling tool into or out of a submarine well; similar damage may be inficted upon a kelly joint during a drilling operation. If the ship is rolling or pitching very sharply, the travelling block |may swing sufficiently to damage the derrick structure. Where rolling or heaving motions of the vessel are not extreme, a swinging travelling block constitutes a Safety hazard to personnel working on the rig floor and such motion of the block hinders efiicient performance of such personnel.

This invention provides a simple, effective, rugged and eflicient apparatus for guiding a travelling block along a selected path of movement vertically of a drilling rig derrick while efectively constraining the block from moving laterally of the selected path. The invention has particular utility in drilling rigs installed aboard floating vessels, but it may be used to advantage in drilling rigs mounted on fixed bases exposed to strong winds, for example.

In brief, this invention provides novel apparatus for guiding a travelling block along a selected substantially Vertical path in a derrick of an oil well drilling rig and -the like. The apparatus includes elongate track means which extend substantially vertically within the derrick along the selected path of travelling block m-ovement. Stay means are provided for positioning the track means within the derrick. Guide means are engaged with the track means for guided movement along the track means in response to movement of the travelling block along the selected path. Pivot means are provided for connectin'g the travelling lblock to the guide means. The pivot means mounts the travelling block for angular movement relative to the track means about an axis which lies substantially normal to the selected path.

The above-mentioned and other features of the present invention are more fully set forth in the following detailed description explanatory of the invention, which description is presented with reference to the accompanying drawings wherein:

FIG. 1 is a front elevation view of a drilling rig mounted on a fioating vessel and equipped with structure in accord with this invention;

FIG. 2 is an enlarged cross-sectional plan view taken along line 2-2 of FIG. 1;

FIG. 3 is a cross-se-ctonal line 3-3 of FIG. 2; and

FIG. 4 is a cross-sectional plan view taken along line 4-4 of FIG. l.

A drilling rig 10 is supported over the main deck 11 of a floating vessel 12 by a structural arch construction 13. The rig includes a floor 14 mounting a rotary 'table 15 over a center well 16 through the hull of the vessel. The rotary table is located directly below a crown |block 17 supported on a watertable 18 of a derrick 19. A travelling block 20 is suspended from the crown block by a cable 21. The cable extends to a drawworks (not shown) on the rig floor. The drawworks is operated to reel in or pay -out the cable from the crown block to cause the travelling block to move toward and away from the rotary table along a line which is substantially aligned with an axis 22 of the rotary table. A lifting hook 23 depends from the travelling block.

' A pair of guide track assemblies 25 are suspended from the derrick watertable by hanger assemblies 26. The guide track assemblies may be fabricated from and I or wide flange beam, but it is preferred that each track assembly be defined by a pair of structural channels 27 (see FIG. 2) aligned in spaced back-to-'back relation with their edge flanges 28 facing away from each other. A cover plate 2.9 extends along the length of each edge of each track assembly. The track assemblies extend from adjacent the watertable along the length of the path along which the travelling block -to be moved. The lower ends of the track assemblies are located a selected distance below the lower limit of this path. As shown in FIGS. 1 and 4, the track assemblies are aligned parallel to each other on opposite sides of rotary table axis 22 in a common Vertical plane extending transversely of the vessel; the plane lies a short distance aft of the axis of the rotary table.

The track assemblies are positioned in spaced parallel relation relative to an up'ward extension of the rotary table axis 'by a plurality of a stay wires 30 connected between the track assemblies and the derrick at a number of locations vertically of the derrick; only one such stay wire installation is shown in FIG. 1 in order that the drawing may be simplified for ease of understanding. At at least two levels vertically of the derrick, the stay wires are tensioned against spring-loaded telescoping snubber assemblies 31 pinned between the track assemblies and 'the adjacent derrick structure.

A rigid guide frame 35 is movably mounted between the guide track assemblies, as shown best in FIGS. 2 and elevation view taken along 3. The guide frame includes a pair of parallel side plates 36 which are spaced apart a distance greater than the width (the dimension fore-and-aft of -the vessel) of the track assemblies. The guide tracks pass between the frame side plates along each Vertical edge of the frame. Between the track assemblies, the frame side plates are secured together by a number of

Vertical spacer plates

37, 38 and 39. An aperture 40 is formed in each side plate centrally of the gui-de frame. Horizontal stifening members 41 are secured to the exterior, i.e., non-opposing, surfaces of the frame side plates to impart further rigidity to the frame.

A roller 43 is mounted to each corner of each side plate for -rotation about an axis 44 normal to the length of the adjacent track assembly and parallel to the -plane of the webs of the channels from which the adjacent track assembly is constructed. Therollers at each corner of the frame are aligned with each other and engage the adjacent web surfaces of the track assembly passing between them. djacent each pair of rollers 43 and toward the central portion of the frame, a horizontal roller 45 is rotatably mounted between the frame side platcs in such position as to engage the cover plate of the adjacent track assembly which opcns 'toward the other track assembly. Adjacent each roller 45, a conical roller 46 is mounted to each side plate for rotation about an axis normal to the side plates. Rollers 46 are located so that they engage the inner surfaces of the fianges which carry the track assembly cover plate With which the adjacent roller 45 is engaged.

Rollers

43, 45 and 46 engage track assemblies 25 so that guide frame 35 cannot cock relative to the track assemblies in either a Vertical or a horizontal plane. The frame is therefore constrained from movement relative to the track assemblies in all directions eX-cept Vertically, and the frame is freely movable 'along and between the track assemblies in a Vertical direction.

The travelling block is connected to the frame via a pivot assembly 50, shown in FIGS. 2 and 3, mounted to the frame within apertures 40 in the guide frame side plates. The pivot assembly includes a rigid bearing housing 51 comprised of a pair of side plates 52, which normally lie in the planes of guide frame side plates 36, and a pair of end plates 53 which extend parallel .to spacer plates 37 between these spacer plates. A travelling block hinge shaft 54 is rotatably journalled in a journal bearing sleeve 55 which is secured to and extends between the pivot assembly side pl-ates adj-acent the upper edge of the pivot assembly. A bearing 'bushing 56 is mounted in the sleeve adjacent each side plate 52. Shaft 54 lies -rnidway between the track assemblies in the Vertical centerplane of vessel 12. The travelling 'block hinge shaft extends forwardly of the pivot assembly and the guide frame to a circular mounting plate 57 which is mounted to the shaft so as to be secure from 'angular and axial movement relative to the shaft. The mounting plate is secured to the rear face of travelling block 2.0 by a plu- -rality of holts 58 threaded into holes tapped in the travelling block. The travelling block hinge shaft is secured in the pivot assembly by a nut 59 threaded onto the rear end of the shaft; a thrust bearing disk 60 is carried 'by the shaft between the pivot assembly and the travelling block and a washer 61 is engaged between side plates 52 and 'the nut and the thrust bearing disk, respectively.

The pivot assembly is hingably mounted to the guide frame by a pivot assembly hinge shaft 64 which has its axis horizontal in the plane in which the track assemblies are positioned. The pivot assembly hinge shaft is carried in a pair of bearing bushings 65 mounted in the opposite ends of a transverse bearing sleeve 6'6. Bearing sleeve 66 is secured to and extends between end plates 53 of the pivot assembly. A pair of washers 67 are engaged 'between bushings 65 and guide frame spacer plates 37 to position the pivot assembly centrally between the spacer plates along shaft 64. Outwardly of the washers from the pivot assembly the shaft has oppositely extending 4 reduced diameter portions 68 which are received in apertures 69 formed in guide frame spacer :

pilates

37 and 38. Beyond spacer plates 38 from the pivot assembly the ends of shaft 64 are threaded to receive nuts 70 which secure the shaft in position in the guide frame.

From the foregoing description it is apparent that travelling block 20 is mounted for movement relative to the derrick only along a selected path aligned with the axis of rotary table 15. While the travelling block can rotate and pivot relative to the derrick about athwartships yand fore-and-aft axes, it 'is constrained so that it can move bodily only along the selected Vertical path in response to reeling in or paying out of cable 21. Any rotating or pivoting motion of the travelling block relative to the derrick is essentially isolated from the track assemblies. As a result, the track guide fianges cannot become deformed so as to hinder movement of the guide frame along the track assemblies. Any swinging moments of the block relative to the derrick about the crown block are essentially isolated from the derrick by reason of the use of hanger assemblies 26 and the use of stay wires 30 and spring-loaded snubber assemblies 31. This means that derrick 19 need be constructed to withstand only the static loads encountered during drilling Operations and the dynamic loads directly attributable to ship motions in a sea. As a result, the derrick may be made as light as possible, thereby producing a direct benefit upon the transverse stability of vessel 12.

All the above features contribute to increased Safety for the personnel who work on the floor of the drilling rig. Since the travelling block cannot move bodily laterally of its desired Vertical path of movement, the tasks of the roughnecks who must move lengths of pipe suspended from hook 23 are made simpler and safer. As a result, drilling Operations may be carried out with increased efliciency.

The invention has been described above in the context of a floating drilling vessel merely for the purposes of setting forth an environment in which the invention has particular utility. Those familiar with the art and science of oil well drilling will readily appreciate that the invention may be used to advantage in fixed-base drilling rigs, particularly where the rig may be subjected to high winds causing the travelling block to swing within the rig derrick. Such persons will also understand that modifications and alterat'ions may be made in the structure described above without departing from the scope of this invention. Accordingly, the foregoing description should not be regarded as limiting the scope and spirit of this invention.

What is claimed is:

1. Apparatus for guiding a travelling block along a selected substantially Vertical path in a derrick of an oil well drilling rig and the like, the apparatus comprising elongate track means extending substantially Vertically within the derrick along the path of travel of the travelling block, stay means for positioning the track means within the derrick, guide means engaged with the track means for guided movement therealong in response to Vertical movement of the travelling block, and pivot means connected between the travelling block and the guide means for mounting the travelling block to the guide means for angular movement of the travelling block relative to the track means about two substantially perpendicular axes substantially normal to the path of travel of the travelling block.

2. Apparatus for guiding a travelling block along a selected substantially Vertical path in a derrick of an oil well drilling rig and the like, the apparatus comprising elongate track means extending substantially Vertically within the derrick along the path of travel of the travelling block, stay means for positioning the track means within the derrick, rigid guide means engaged with the track means for guided movement therealong in response to Vertical movement of the travelling block and extending from the track means to adjacent the travelling block,

and pivot means connected between the travelling block and the guide means for mounting the travelling block to the guide means for movement of the travelling block relative to the guide means about two substantially perpendicular axes substantally normal to the path of travel of the travelling block.

3. Apparatus according to claim 2 whereiu the track means comprises a pair of elongate track assemblies disposed in a common plane parallel to but spaced from said selected path.

4. Apparatus according to claim 3 Wherein the pivot means includes a travelling block hinge shaft defining one of said two axes secured to the travelling block and extending toward the guide means normal to the selected path and to said common plane, a pivot assembly rotatably receiving and mounting the travelling block hinge shaft, a pivot assembly hinge shaft defining the other of said two axes mounted to the guide means and disposed normal to said selected path in said common plane, and means rotatably mounting the pivot assembly to the pivot assembly hnge shaft.

5. Apparatus according to claim 3 wherein the guide means extends rigidly between the track assemblies and including means for movably engaging the guide means with the track assemblies and for constraining the guide means from movement relative to the track assemblies in all directions except parallel to the selected path.

6. Apparatus according to claim 5 wherein each track assembly extends partially within the guide means toward the other track assembly, each track assembly within the guide means having a substantially T-shaped cross-sectional configuration in a plane normal to said selected path, and the means for movably engaging the guide means with the track assemblies comprises roller means carried by the guide means and engaging each track as sembly on opposite sides of the stem of said T and on opposite sides of each arm of the T.

7. Apparatus according to claim 6 wherein the roller means includes two pairs of roller sets, each pair of roller sets being engaged with a respective track assembly, each roller set of one pair engaging the adjacent track assembly as stated in claim 7 at a location spaced along the adjacent track assembly from the other roller set of said one pair.

8. Apparatus according to claim 2 wherein said derrick is mounted above the hull of a floating drilling vessel and said two axes extend longitudinally and transversely of the hull, respectively.

References Cited UNITED STATES PATENTS 3,280,520 10/1966 Woolslayer 187-95 3,281,122 10/1966 Jenkins 254-1391 EVON C. BLUNK, Primary Examiner.

H. C. HORNSBY, Assistant Examner.

UNITED sTATEs PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 ,336 ,003 August l5 1967 Robert Curtis Crooke "et al.

It is hereby Certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below In the headng to the printed specification, lines 5 and 6, for `'a corporation of California" read a Corporation of Delaware--; column 2, line 50, after "block" insert is column 6, line 13, for the claim reference numeral "7" read Signed and sealed this 5th day of November 1968.

(SEAL) Attest:

EDWARD J. BRENNER Commissioner of Patents Edward M. Fletcher, Jr.

Attesting Officer

Claims

1. APPARATUS FOR GUIDING A TRAVELLING BLOCK ALONG A SELECTED SUBSTANTIALLY VERTICAL PATH IN A DERRICK OF AN OIL WELL DRILLING RIG AND THE LIKE, THE APPARATUS COMPRISING ELONGATE TRACK MEANS EXTENDING SUBSTANTIALLY VERTICALLY WITHIN THE DERRICK ALONG THE PATH OF TRAVEL OF THE TRAVELLING BLOCK, STAY MEANS FOR POSITIONING THE TRACK MEANS WITHIN THE DERRICK, GUIDE MEANS ENGAGED WITH THE TRACK MEANS FOR GUIDED MOVEMENT THEREALONG IN RESPONSE TO VERTICAL MOVEMENT OF THE TRAVELLING BLOCK, AND PIVOT MEANS CONNECTED BETWEEN THE TRAVELLING BLOCK AND THE GUIDE MEANS FOR MOUNTING THE TRAVELLING BLOCK TO THE GUIDE MEANS FOR TRACK MEANS ABOUT TWO SUBSTANTIALLY PERPENDICULAR AXES TRACK MEANS ABOUT TWO SUBSTANTIALLY PERPENDICULAR AXES SUBSTANTIALLY NORMAL TO THE PATH OF TRAVEL OF THE TRAVELLING BLOCK.