US1826946A

US1826946A - Crown block

Info

Publication number: US1826946A
Application number: US120971A
Authority: US
Inventors: Minor Burt Stanley
Original assignee: Individual
Current assignee: Individual
Priority date: 1926-07-07
Filing date: 1926-07-07
Publication date: 1931-10-13
Anticipated expiration: 1948-10-13

Description

Oct. 13, 1931. B. s. MINOR CROWN BLOCK 4 Sheets-Sheet. 1

Filed July '7, 1926 INVENITOR. Bum- 6. MINOR ATTORNEY.

B. S. MINOR Oct. 13, 1931,

cnown BLOCK Filed y 7. .1926

4 Sheets-Sheet 2 I NVEN TOR.

B RT 5'. MINOR A TTORNE Y.

Oct. 13, 1931. I B. s. MINOR 1,826,946

CROWN BLOCK Filed July 7, 1926 4 Sheets-Sheet 3 I NVEN TOR.

A BURT S MINOR ATTORNEY.

"B. s. MINOR Oct. 13, 1931;

CROWN BLOGKv Filed July 7, 1926 4 Sheets-Sheet 4 INVENTOR. BURT S Muvo A TTORNE Y.

Patented Oct. 13, 1931 BURT STANLEY MINOR, OF SAN PEDRO, CALIFORNIA CROWN BLOCK Application filed July 7,

This invention has relation to crown blocks utilized on derrick structures for guiding cable lines in the drilling of oil wells and other operations incidental thereto.

In the standard form of crown blocks now generally employed in oil well drilling operations it has been the practice to arrange the sheavesin such relation to each other that the pull of the various cable lines shall be as nearly vertical as possible in order to lessen the wear on the lines and sheaves during hoisting and lowering operations. In order to attain such results it has been customary to arrange some of the sheave bearings so thatthey may be adjusted transversely in the crown block, and as a consequence the diameter of the sheaves in such cases must be reduced to a minimum to allow room for adjustment. Further, as the sheaves are disposed in the same direction it is impossible to bring the same close enough to line up with the sheaves of the travelling block and as a result cause an untrue tracking of the cable lines with resultant wear on the lines and sheave flanges. It has also been the purpose to arrange the sheaves, whereby sheaves of.

large diameter may be used to minimize the stresses imposed upon the lines by the smaller diameter sheaves.

I It is therefore a main object of the present invention to provide a crown block construction in which the diameter of sheaves employed are proportionate to the diameter of the cable lines used therewith, whereby to.

greatly lessen the wear of the lines due to bending friction.

Another ob]ectis to provide an arrangement of sheaves in which the starting linesfrom the bull and calf draw works wheels will uniformly spool, thereby rendering it unnecessary to move or skid the crown block at the derrick top, or to move the equipment on the derrick floor to correspond.

Another object is to provide an arrangement of the crown block sheaves in which the cable lines will track from one sheave to another, thereby eliminating side friction in the lines during their operation.

A further and important object is to increase the diameter of the sheaves over which 1926. Serial No. 120,971.

the fast moving linesoperate, and to decrease the diameter of the sheaves over which the slow moving lines operate, in order to eliminate frictional heat generated by bending strains.

Still another object is to arrange the various line sheaves that the lines leading therefrom may be fanned in the desired direction without destroying the line-up or tracking of the pulley sheave grooves.

In the disposition of the sheaves of the present invention the cable lines leading therefrom to the travelling block will be so directed thereto that the block will at all times during its operation maintain a substantially vertical position, thereby obviating undue wear on the lines, and preventin accidental displacement of the derrick fingerboard and other structures.

The above and other objects are attained by the construction described herein, and illustrated in the accompanying drawings, in which:

Fig. 1 is a side elevation of the upper end of a well derrick showing the lines from the crown block sheaves leading to the travelling block.

Fig. 2 is an end elevation of the above.

Fig. 3 is a plan view of the crown block.

Fig. 4. is a diagrammatic view illustrating a complete threading of the various cable lines with respect to the crown and travellin blocks and the derrick equipment.

Fig. 5 is a view similar to the above showing the threading of the crown block when only three of the travelling block sheaves are used.

Fig. 6 is another similar view showing the method of threading the crown block when Only two of the travelling block sheaves are used.

The present invention contemplates a. novel arrangement of crown block sheaves (here shown as seven) in which the sheaves of greatest diameter and over which pass the fast moving cable lines are all disposed over and at right angles to the smaller casing, sand and spuddin sheaves over which pass the slow moving 'nes.

Referringnow more particularly to the drawings, 10 designates the upright derrick timbers, four in number connected together at their upper ends with cross timbers 11. oppositely-disposed on a pair of the cross timbers 11 are similar cross timbers 12, all bolted together to form a rigid structure. Disposed on top of timbers 12 are a plurality of channel beams arranged in

pairs

13, 14, 15, 16 in parallel rows and suitably secured to the cross beams 12 by which they are su orted.

ounted in bearings 17, 18, between the oppositely disposed channels of beam pairs, 13, 14 and 15, 16, are a pair of

easing sheaves

19, 20, of relatively small diameter utilized when handling well casing. Secured in a strap bearing 21 bolted to a pair of brackets 22 dis osed on the upper flanges of the opposite y disposed channel members of the pairs of beams 14, 15, is a spudding sheave 23 over which passes the spudding line 24 from the bull wheel 25 located on the derrick floor. Mounted in bearings 27, secured to the top flanges of the oppositely disposed beams of the beam pairs 14, 15 is a sand line sheave 28, over which passes the cable line 29 from the sand reel 30.

Disposed upon the pairs of

channel beams

13, 14, 15 and 16 and extending in the same direction are I-

beams

31, 32, 33 and 34, that in turn support a pair of channel beams 35 that extend transversely from beam 31 to beam 34, (see Fig. 2). Mounted on and secured to the uppermost flanges of beams 35,

and midway of their ends are a pair of oppositely disposed vertically extending bearings 36 designed to support a lurality of downwardly extending strap p ates 37 between which are mounted in bearings (not shown) the three fast moving casing sheaves of the

greatest diameter

39, 40, and 41, the operating cable lines passing thereover and downwardly around the sheaves of the travelling block, the bearings in the strap plates for the casing sheave pins being arranged in staggered relation.

It will be noted that the three last mentioned sheaves are disposed at substantially right angles to the sheaves disposed therebelow, sheave 40, being directly over the center of the well with the two

others

39, 41, at each side. By this arrangement the. fastest mov ing cable lines are operated directly over the center of the well, and as the sheaves are of large diameter the excess of frictional heat generated by bending strains is largely obviated. This feature of the crown block construction is considered one of the most important features of the invention, as by such an arrangement of the various sheaves the starting lines from the draw works and the calf wheel will uniformly spool, and the lines leading from the sheaves to the travelling block will maintain said block in nearly verof the block, upwardly to crown sheave 20 then downwardly to sheave 55 of the block, upwardly to crown sheave 19, and thence downwardly where it is made fast to the calf wheel 3.

It f equently happens that when the drilling tools, pipe casings, and like structures to be lifted are not excessively heavy, that some of the sheaves in the crown block may be dispensed with and in Fig. 5 is shown the method of threading the cable lines when only four sheaves are employed. The cable line 42 from the draw works 50, passes upwardly and over crown sheave 40, downwardly to sheave 52 of the travelling block, thence upwardly and over crown sheave 39, downwardly and around sheave 53 upwardly and over crown sheave 20, downwardly and around sheave 55, upwardly and over crown sheave 19, and

finally downwardly to the calf wheel 43.

When lifting comparatively light objects onl two sheaves of the crown block are genera 1y employed, and in Fig. 6 is shown diagrammatically the threading arrangement in such cases.

The main operating cable line 42 from the draw works 50 passes upwardly and around sheave 39, downwardly to block sheave 53, upwardly and over sheave 20, downwardly and around block sheave 55, upwardly over sheave 19, and thence to the calf wheel.

The sand reel line 29 passes in each instance from the reel 30, upwardly and over sand sheave 28, while the bull wheel line 24 passes upwardly from the bull wheel 25 around the crown sheave 23. The sand reel line is utilized during drilling for operating the bailer or other light hoisting from the derrick The bull wheel line is so arranged that its free end is disposed directly over the center of the derrick.

It will be apparent from the above arrangement of the various sheaves of the crown block, the cable lines will lead on and oil practically straight with the sheave grooves, without imposing side pressure on the groove flanges, or creating any appreciable stress upon the cables due to bending friction. Further, by the arrangement of the sheaves one set above another it will be possible to condense the same so that the lines therefrom will lead in a more nearly vertical direction to the travelling block. Also by arranging the fast quence the cable lines leading to the travelling block will maintain the same in a substantially vertical position.

While the face width of the grouped crown block sheaves are illustrated as smaller than the face width of the traveling block sheaves, it will be understood that I do not wish to be limited to the exact proportional relation of said sheaves, as the face width of the grouped crown block sheaves may be formed equal to the face width of the sheaves of the traveling block without substantially altermg or affecting the directional movement of the cable lines.

'What I claim is:

1. The combination with a traveling block, of a crown block construction comprising two groups of cable sheaves disposed one above the other, the extreme face width of one group being approximately equal to the face width of the sheaves of the traveling block, the extreme face width of the other group of sheaves being approximately equal to the diametrical dimension of the sheaves of the traveling block, whereby the cable lines leading from the crown block sheaves to the sheaves of the traveling block will .enter and leave the grooves of the traveling being disposed'one above another and sesheaves for engaging fast moving casin cured in rigid relation to each other, grouped shafts for mounting casing sheaves for carrying slow moving cable lines mounted in bearings on the lower frame, said shafts being disposed in arallel relation,and a plurality of centra ly disposed. grouped shafts mounted in bearings on the upper frame. at right angles to the shafts in the frames therebelow for mounting relativelylarge casing lines, the extreme face width of each sha t group being substantially equal to the face Width or diameter of the traveling block sheaves suspended by the cable lines leading.

from the same; v

3. A crown block construction for oil well derricks comprising a plurality of horizontally disposed metal frames bolted together one above another a pair of casing sheavesmounted in bearings on the lower frame, said sheaves being adapted to engage the slow moving casing sheave lines, and a group of sheaves disposed on shaftsmounted in bearings on the uppermost frame, said sheaves being disposed at right angles to the pair of sheaves disposed directly therebelow, the extreme face width of each group being substantially equal to the face width or diameter of the traveling block sheaves suspended by the cable lines leading from the crown block, whereby the cable lines will be directed to the sheaves of the traveling block in a vertical direction and-in approximate parallel relation.

4. A crown block construction for oil well derricks comprising a plurality of frame members secured together one above another, a shaft for mounting a spudding sheave and a shaft for mounting a sand line sheave disposed in bearings on the lowermost frame, shafts for mounting casing sheaves carrying slow moving lines disposed on the upper frame, a sheave on either side of the sand line and spudding line sheaves, said shafts being disposed in parallel relation to the spudding and sand line sheaves, and a plurality of centrally disposed shafts mounted in bearings on the uppermost frame at right angles to the shafts in the frames therebelow for of the various grouped sets of casing sheaves being substantially equal to the face Width or diameter of the traveling block sheaves lo cated below the crown block, the sheaves of which the various cable lines engage, whereby the groups of easing cable lines will be directed to the sheaves of the traveling block in a substantially vertical direction and in approximately parallel relation.

5. A crown block construction for oil well derricks comprising a plurality of frames 1 disposed in parallel relation to the sand and spudding line sheaves, a plurality of strap plate bearings centrally disposed on the uppermost frame and rigidly secured thereto, and a plurality of sheaves for carrying fast moving casing lines each provided with trunnions engaging the strap plate bearmg's, sa1d sheaves being disposed at right angles to the sheaves in the frames therebelow.

6. The combination with a traveling block, of a crown. block construction comprising two groups of cable sheaves disposed one above the other and at approximately right angles to each other, the extreme face width of one group being approximately equal to the face width of the sheaves of the traveling block, while the extreme face width of the other group is approximately equal to the diametrical dimensions of the sheaves of the traveling block, whereby the, cable'lines leading from the groups of sheaves of the crown block to the sheaves of the traveling'block will enter and leave the grooves of the traveling block sheaves at a minimum angle from the vertical.

In witness that I claim the foregoing I 5 have hereunto subscribed my name this 9th day of June, 1926.

BURT STANLEY MINOR.