US1928958A - Crown block - Google Patents

Description

Oct. 3, 1933. F J. YOUNG Er AL 1,928,958

CROWN BLOCK Filed Nov. 16, 1931 3 Sheets-Sheet l Inventor.;

www@ By 0192@ a@- Oct. 3, 1933., F. J. YOUNG ET AL v 1,928,958

CROWN BLOCK Fi1ed Nov. 1e, 1931 s sheets-'sheet 2 Oct. 3, 1933. F` 1, YOUNG Er AL CROWN BLOCK Filed Nov. 16. 1931 3 SheetS-Shst A 3v Attorneys Patented Oct. 3, 1933 PATENT OFFICE CROWN BLOCK Forrest J. Young and John D. Spalding, Los Angeles, Calif., assignors to The National Supply Company, Toledo, Ohio, a corporation of Ohio Application November 16, 1931 Serial No. 575,208

16 Claims.

l This invention relates to crown blocks adapted to be installed on the water table of an oil well drilling rig of the type commonly .employed in the rotary drilling of wells.

An object of this invention is to provide a line reeving structure including a crown block and a traveling block wherein the line reeved between the crown block and the traveling block is. maintained parallel to permit the traveling block to hang centrally over the well withvany number of lines, and in which crown block cross-over sheaves are provided above the main sheave structure, permitting the use of large cross-over sheaves, and furthermore, greatly simplifying the structural support for all of the sheaves.

-Another object of this invention is to provide a reeving structure, including a crown block and a traveling block, the crown block being so constructed that its main shaft is maintained parauei with the shaft of the traveiing mock and which permits the maintaining of the lines reeved between the crown block and the traveling block substantially parallel, and permits the traveling block to hang centrally over the well with any number of lines, and wherein the line reeving between the crown block and the traveling block may be increased or decreased as desired in a progressive or successive manner over the sheaves of the crown block and the traveling block with a minimum of labor, and, in the case of adding lines to the structure, without unreeving any of the previously reeved sheaves of the crown block or traveling block.

` Another object of this invention is to provide a crown block wherein the sheaves may be of maximum size andviwherein the sheaves are so arranged as to permit the wire rope to be reeved over the sheaves in parallel arrangement, and thereby minimize the wear and stress ordinarily imposed upon such wire rope.

Another object of this invention is to provide a crown block including a base structure upon which a shaft is mounted and upon which a plurality of sheaves are journaled in face to face relation and upon which base structure crossoverbeams are mounted substantially parallel with the main shaft and beyond the periphery of the sheaves of the main shaft, and which crossover beamssupport a shaft to the ends of which there are secured cross-over sheaves of relatively large diameter.

Another object of this invention is to provide a crown block including a shaft having a plurality of sheaves journaled thereon on roller bearings which are mounted in end to end relation on the shaft, and which bearing structures include races which are slip-fitted on the shaft and held in position by spring-pressed dowels carried by the shaft.

Another object of this invention is to provide a crown block wherein the sheaves of the main' shaft are lubricated through spring-pressed dowels which are utilized for maintaining the bearing on the shaft in position.

Other objects and advantages of this linvention it is believed will be apparent from the following detailed description of a preferred embodiment thereof as illustrated in the accompanying drawi ings.

In the drawings:

Figure 1 is a reeving diagram of the crown block embodying our invention.

Figure 2 is a similar reeving diagram illustrating the reeving of a greater number of lines over the crown block embodying our invention.

Figures 3 and 4 are additional reeving diagrams of the'crown block embodying our invention illustrating the progressive reeving thereof.

Figure 5 is a side elevation partly in vertical midsection of the crown block embodied in our invention.

Figure 6 is a sectional end elevation taken substantially on the line 6-6 of Figure 5.

Figure '7 is a fragmental sectional view illustrating the manner of mounting the retaining collar and thrust washer on the main shaft of the crown block.

Figure 8 is an elevation of ra modied form of crown block embodying our invention.

Figure 9 is an end sectional view thereof, taken substantially on the line 9-9 of Figure 8 with the sheaves illustrated in edge elevation.

Figure l0 is an enlarged sectional view of one of the cross-over sheaves of the rst modication of our invention, `showing the dowel and lubricating means thereof.

In the preferred embodiment of our invention illustrated in the accompanying drawings, 1 indicates the main shaft of the crown block upon which a plurality of sheaves 2, 3, 4 and 5 are journaled. Positioned above the main shaft 1 and at right angles thereto and spanning the sheaves 2, 3, 4 and 5 is a cross-over shaft V6. journaled near the ends of whichare cross-over sheaves 7 and 8.

The traveling block embodied in our invention includes a shaft 9, which is -substantially parallel with the shaft 1 of the crown block. Journaled on the shaft 9 of the traveling block'lo are traveling block sheaves 10, 11, 12, 13 and 14.

sheaves journaled thereon.

The main shaft l of the crown block is herein illustrated as having journaled thereon four main sheaves, while the traveling block shaft 9 is herein illustrated as having ve traveling block It is however to be understood that this particular number of sheaves is used merely for the purpose of illustration and that sheaves may be either added to or removed from the crown block shaft 1 and the traveling block shaft 9 as desired Without departing from our invention.

With the assembly of crown block sheaves and traveling block sheaves as above set forth, substantially parallel reeving of the lines reeved over the sheaves of the crown block and traveling block may be had and maintained, and the traveling block may be caused to hang directly over the'center of thewell irrespective of the number of lines which are reeved between the crown block and the traveling block.

In-order to accomplish this parallel reeving of the lines, and the maintaining of the traveln ing block centrally over the well, we prefer to reeve a line 15 between the crown block and the traveling block as will hereinafter be set forth. With the reeving as hereinafter set forth, we are enabled to obtain a progressive reeving of the line between the crown block and the traveling block so that as lines are added to this reeving it is not essential to unreeve any of the pre- ,viously reeved sheaves of the combination, but is merely necessary to progress in the reeving along the sheaves journaled on the shafts 1 and 9 of the crown block and traveling block respectively.

To accomplish this reeving, the line 1511s reeved as illustrated in Figure 1 first over the crossover sheave 8, then over the end sheave 14 of the traveling block, then over the other crossover sheave '7, and back to the traveling block 0 over the opposite end sheave 10 and then over the end sheave 2 of the main shaft 1 of the crown block.

With the reeving as above set forth, there is provided what is commonly known as a four-line reeving wherein the four lines reeved between the crown block and the traveling block are substantially parallel, and the traveling block is suspended in the derrick directly over the well. With this reeving the first line thereof passing between' the cross-over sheave 8 and the end sheave 14 of the traveling block is a stationary line and is positioned to the right of the derrick man working upon the fourble board opposite the drawworks side of the derrick. This enables the derrick man to swing the traveling block while ascending or descending in order to get the elevators connected with the traveling block to catch around the drill stem under drilling operation. With this stationary line positioned at this point, the derrick man can hold this line and control the swinging action of the traveling block without any risk of injury from afast-moving line.

Figures 2, 3 and 4 illustrate what is commonly termed as six, eight and ten line reevings, and it will be noted that these additional line reevings between the crown block and traveling block are obtained by merely progressively reeving the line 15 over the sheaves 3 to 5 of the crown block, and 11 to 13 of the traveling block; that is, in obtaining the six-line reeving of Figure 2, the line after passing over the end sheave 2 of the crown block .shaft`1, is passed over the next succeeding sheave 11 of the traveling block, and then up over the next succeeding sheave 3 of the crown block.

To obtain the eight-line reeving, this progressive reeving is merely continued, and the line passed down over the traveling block sheave 12 and then up and around the crown block sheave 4.

To obtain a ten-line reeving, this same progressive action is followed, and the line after passing the sheave 4 is passed down over the sheave 13 of the traveling block and up around .the sheave 5 of the crown block. Additional line reevings may obviously be obtained by merely adding sheaves toshafts 1 and 9 of the crown block and traveling block respectively, as desired.

The end 16 of the line 15 may be passed over the calf wheel, or may be anchored as desired, and is the ldead end of the line. The end 17 of the line 15 passes to the drawworks and is the live end of the line.

The crown block embodying our invention briefly includes a rectangular base structure 18 illustrated as formed of I-beams 19 connected at their ends by means of channel irons 20. The shaft 1 of the crown block is mounted in boxes 21 secured to the upper flanges of the I-beams 19.

The sheaves 2, 3, 4 and 5 are journaled on the shaft 1 in face-to-face relation upon roller bearings 22 which are mounted on the shaft 1 in endto-end relation separated by partition washers 23. The bearings 22 include inner races 24 which are slip-fitted on the shaft 1 and are held from rotation on the shaft 1 by means of springpressed dowels 25 which pass into holes 26 formed in the races 24. The partition washers 23 are mounted on the shaft 1 between the inner races 24 and hold the bearings 22 from endwise movement along the shaft 1. The washers 23 are of a less exterior diameter than the inner diameter of the hubs 261 of the sheaves 2, 3, 4 and 5. The hubs 261 of the sheaves 2, 3, 4 and 5 are formed with radially extending spacer flanges 27 to form side thrust bearing areas 28 between the hubs of the sheaves. These sheave hub flanges 27 -abut face-to-face without any intervening structure and the assembly of sheaves upon the shaft 1 is held in position by means of end collars 29 within which thrust washers 30 are positioned to take the end thrust of the complete set of sheaves 2, 3, 4 and 5 mounted on the shaft 1.

The collars 29 are split collars and they are clamped to the shaft 1 and are held in position by means of dowels 31 which register with dowel holes 32 in the shaft 1 to prevent longitudinal or radial displacement of the collars 29. The collars 29 are provided with a cylindrical shroud 33 which projects from the face of the collars 29 to form an enclosure for the end thrust washers 30 to prevent a worn or broken washer dropping from the shaft 1 to the derrick floor. A dowel 34 is registered with a hole in the thrust washer 30 to prevent the washer from rotating and thereby confine the thrust wear to the inexpensive replaceable washer 30.

Mounted across the I-beams 19 are cross-over beams 35. The cross-over beams 35 are mounted in position parallel with'the main shaft 1l and beyond the sides of the group of sheaves 2, 3, 4 and 5 mounted on the main shaft 1. The crossover shaft 6 is secured to the cross-over beams 35 by means of boxes 36. Cross-over shaft 6 spans over the shaft 1 and is positioned at rightangles to shaft 1. Journaled on the cross-over shaft 6 near the ends thereof and adjacent to the cross-over beams 35, are the cross-over rick floor.

Cross-over sheaves 7 and 8 are mounted on anti-friction roller bearings 37 which run on inner races 38 mounted on the cross-'over shaft 6. Each sheave 7 and 8 is retained in place on the shaft 6 by means of split collars 39 which are clamped tothe shaft 6 and are secured against longitudinal and radial movement by means of dowels 40 which register with holes 41 in the shaft 6.

Thrust washers 42 are enclosed in the cylindrical shroud 43 of the split collars 39 to prevent worn thrust washers 42 from dropping to the der- The shroud 43, and vlikewise the shroud 33,'form protective seals-'around the joint between the sheave hub face and the washers 42 and 30 to exclude any foreign substance from entering the bearings 22 or 37. Sheaves 7 and 8 are larger in diameter than thel center line spacing between the grooves in the outside main sheaves 2 and 5. The projection of the groove centers of the main sheaves upward to the diameter of the cross-over sheaves 7 and 8 show five spaces approximately of equal width. The purpose of this proportion will be evident from the description of the reeving as heretofore set forth. It will be `obvious from the foregoing that the casing line sheaves are mounted on the 'main Ashaft in equal spacing axially of the shaft, and that the approximate spacing of the sheaves is determined by dividing the diameter'of the crossover sheave by a factor equal to one plus the number of casing line sheaves on the main shaft.

The relative location in size of the main and cross-over sheaves results in ample clearance as indicated at 44, 45 and 46, so as to permit the erector, or derrick man, to reeve the block without any danger of injury due to restricted clearances.

The cross-over sheaves 7 and Bare spaced equidistant with respect to the vertical center line of the main sheaves 2, 3, 4 and 5, and with the axis of the shaft 6 located centrally with respect to theA group of main sheaves 2, 3, 4 and 5. The horizontal central distance between the group of sheaves 7 and 8 is equal to, or slightly in excess of, the diameter of the main sheaves 2, 3, 4 and 5.

In the reeving diagrams of Figures 1 to 4 inclusive, the crown block and traveling block are shown as reeved from right to left, but it is evident that the same reeving may be provided from the opposite hand, that is, from left to right. The opposite reeving, that is. from left to right, is necessary in case the calf wheel is mounted in the derrick on the side to the left of the drawworks side.

In case it is necessary to obtain additional lifting power over that obtained with a ten-line reeving, the calf wheel, or dead end 16, of the line 15, can be attached to the top clevice cornmonly used on traveling blocks, and thereby obtain the lifting effect of eleven lines.

The main shaft 1 is reduced in diameter at one end and upon this reduced diameter there is mounted a rotatable sheave 47. This sheave is for the catline which is used in derricks for lifting various tools and equipment, and is located substantially in line with the cathead on the drilling side of the drawworks.

A split collar 48 rits in a recess 49 on the reduced end of the shaft 1 to prevent the sheave 47 from moving off the shaft `1. A sheave guard 50 is formed integral with the upper portion of the collar 48 and extends over the upper portion 0f the sheave 47 to prevent the catline from jumping out of the sheave groove.

A d owel 51 retains the guard 50 against any radial displacement.

In the erection of this crown block on the water table of the drilling rig, the lower and upper shaft assemblies are handled as units so that itis only necessary to clamp the shaft assemblies into position by means of the hinged straps which are part of each box- 21 and 36., The unit structure thus provided results in expediting the time of erection, and provides an element of safety not heretofore possible in the placing of the crown block on the water table of the derrick.

In orderto provide forv lubrication of the sheaves 2, 3, 4 and 5, and the sheaves 7 and 8, we prefer to provide the following means:

The shaft 1 is drilled axially from end to end. y

Pipes 52 are mounted longitudinally of the hole thus drilled in the shaft 1. Lubrication plugs 53 are mounted within radial bores in the shaft 1.

Couplings 54 are secured to the plugs 53 and to the respective pipes 52.

Secured to the outer end of the pipes 52 are grease fittings 55. Mounted within the radially bored holes of the shaft 1 are springs 56 which are interposed between lubrication plugs 53 and the dowels 25 to normally urge the dowels 25 outward into the dowel holes 26 formed in the inner races 24 of the bearings 22.

The dowels 25 are bored axially so that the bearings 22 are lubricated through the dowels 25 from the grease fittings 55 secured to the longitudinally extending pipes 52.

In a similar manner, the bearings 37 of the sheaves 7 and 8 are lubricated by means of longitudinal bores 57 and connecting radial bores 60 of the cross-over shaft 6. Springs 61 are interposed between the longitudinal bores 57 and dowels 62 mounted within the radial bores of the shaft 6. The dowels 62 fit within dowel holes formed in the inner race members 38 of the bearings 37 and the dowels 62 are bored axially to permit the lubrication of the bearings 37 therethrough. Grease fittings 63 are secured in the outer ends of the longitudinal bores 57. Each sheave is therefore lubricated separately.

In each case the dowels 25 and 62 are of a reduced diameter at their outer end to fit the dowel holes formed in the inner races of the bearings 22 and 37 so that a shoulder is provided preventing the springs from thrusting the dowels through the inner races to foul the bearings 22 and 37.

The dowel holes formed radially of the shaft 1 are formed in staggered relation around the shaft 1, thereby only inappreciably impairing the strength of the shaft.

The inner races 24 and 38 of the bearings 22 and 37 have two dowel holes diametrically opposite each other for the purpose of increasing the operating life of the races. Since the load on the sheaves is always downward, the wear only takes place on the upper surface of the inner race. After the races become worn, they may become rotated through 180 to register the opposite dowel hole with the dowel and thereby present a new and unworn bearing surface to the rolling action of the bearings 22 and 37 respectively.

The modified form of my invention illustrated in Figures 8 and 9 is entirely similar to that already described with the exception of the crossover shaft 6a thereof so that similar numerals have been used to designate similar parts with the addition of an exponent a In this modified structure the shaft 6a is what we term a bridge shaft which is flattened at its central section to fit between the two central sheaves 3a and 4a of the main shaft 1a. This structure allows a reduction of the overall height of the crown block with a reduction of weight.

of the structure'.

Having fully described our invention, it is to be understood that we do not wish to be limited to the details herein set forth, but our invention is of the full scope of the appended claims.

1. In a-crown block, the combination of a base structure, a shaft mounted across the base structure, a plurality of sheaves journaled on said shaft within the base structure, cross-over beams mounted across said base structure parallel with said shaft and beyond the periphery of said sheaves, a cross-over shaft spanned between the cross-over beams and secured thereto, and a sheave journaled on each end of said shaft on the inside and adjacent said beams.

2. In a crown block, the combination of a base structure, a shaft secured to the base structure, a plurality of sheaves journaled on the shaft, the sheaves being journaled on said shaft on roller bearings held in spaced relation on said shaft, said sheaves having hubs and radially extending hub flanges in face-to-face contact, end thrust members secured to said shaft at the end thereof to contact the outer hub flanges of the end sheaves, cross-over beams mounted on and extending upwardly from the base structure on opposite sides of the group of sheaves mounted on the first said shaft, across-over shaft spanning said sheaves and secured at its end to said beams, a sheave journaled on the cross-over shaft near each end thereof at the sides of the group of sheaves mounted on the rst said shaft.

3. In a drilling rig, the combination of a crown block including a main shaft, a plurality of main sheaves journaled on the main shaft, a cross-over shaft supported above the main shaft and extending across the main shaft, a crossover sheave mounted on each end of the crossover shaft beyond the sides of the group of main sheaves, a traveling block having a plurality of sheaves rotatable on axes substantially parallel with the main shaft, and a line reeved between said sheaves rst over one of said 'cross-over sheaves, then under one end sheave of the traveling block, then over the other cross-over sheave, then under the sheave at the other end of the traveling block, and then over one of the main sheaves.

4. In a drilling rig, the combination. of a crown block including a main shaft, a plurality of main sheaves journaled on the main shaft,` a cross-over shaft supported above the main shaft and extending across the main shaft, a cross-over sheave mounted on each endl of the cross-over shaft beyond the peripheries of the group of main sheaves, a traveling block having a plurality of sheaves rotatable on axes substantially parallel with the main shaft, and a line reeved between said sheaves first over one of said cross-over sheaves, then under one end sheave of the traveling block, then over the other cross-over sheave, then under the sheave at the other end of the traveling block, then over one of themain sheaves, and then reeved progressively under and over the sheaves of the traveling block and crown block, respectively, from end to end of said traveling block and crown block.

5. In a crown block, the combination of a shaft, a plurality of sheaves journaled on said shaft, roller bearings mounted in end-to-end relation on said shaft and on which said sheaves are journaled, said roller bearings including inner races slip-fitted on the shaft, spring-pressed dowels carried by said shaft and adapted to hold said inner races from rotation on the shaft, and means extending longitudinally of said shaft and connecting with said spring-pressed dowels for lubricating said bearings.

6. In a crown block, the combination of a base structure, a shaft mounted across the base structure, a plurality of sheaves journaled on said shaft within the base structure, cross-over beams mounted across the base structure parallel with said shaft and beyond the peripheries of said sheaves, a cross-over shaft supported by said beams and spanned therebetween above the peripheries of said sheaves, and a plurality of crossover sheaves mounted on said cross-over shaft bep yond the peripheries of said sheaves.

7. In a crown block, the combination of a base structure, a shaft mounted across the base structure, a plurality of sheaves journaled on said shaft within the base structure, cross-over beams mounted across the base structure parallel with said shaft and beyond the peripheries of said sheaves, a cross-over shaft above the mainshaft and extending between the sheaves thereon and having a cross-section throughout the portion between the sheaves with a vertical major axis greater than the horizontal minor axis, and a plurality of cross-over sheaves mounted on said cross-over shaft beyond the peripheries of the first said sheaves.

8. In a crown block, the combination of a shaft, a plurality of sheaves journaled on said shaft, roller bearings mounted in end-,to-end relation upon said shaft and having axial freedom on said shaft and upon which roller bearings said sheaves are journaled, said roller bearings including inner races, and separator elements between the roller bearings and of less diameter than the maximum diameter of the roller bearing assemblies so that the hubs of the sheaves are positioned in face-to-face contact on said shaft.

9. In a block, the combination of a shaft, a plurality of sheaves journaled on said shaft, roller bearing assemblies mounted in end-to-end relation upon said shaft and upon which said sheaves are journaled, said bearing assemblies including inner races, and separator elements between the bearing assemblies which are of less external diameter than the maximum diameter of the roller bearing assemblies, so that the sheaves are free to have axial movement on the shaft independent of the bearing assemblies.

10. In a multiple sheave assembly, the combination of a shaft, a plurality of sheaves journaled on said shaft, roller bearing assemblies mounted in end-to-end relation upon said shaft and upon which said sheaves are journaled, said bearing assemblies including inner races, and separator elements between the bearing assemblies which are of less diameter than the bore in saidl sheaves, so that the sheaves can be assembled on and removed from said shaft without disturbing the roller bearing assemblies, and means engaging the outer hub faces of the two outer sheaves of said group to take any axial thrust from said sheaves.

11. In' a multiple sheave assembly, the combination of a shaft, a plurality of sheaves journaled on said shaft, roller bearing assemblies mounted in end-to-end relation upon said shaft and upon which saidv sheaves are journaled, said bearing assemblies including inner races, and separator elements between the bearing assemblies which are of less diameter than the bore in saidv sheaves, so that the sheaves can be assembled on and removed from said shaft Without disturbing the roller bearing assemblies, and renewable thrust bearing elements engaging the outer hub faces of the two outer sheaves of said group to take any axial thrust from said sheaves.

12. In a multiple sheave assembly, the combination of a shaft, a plurality of sheavesjournaled on said shaft, roller bearing assemblies mounted in end-to-end relation upon said shaft and upon which said sheaves are journaled, said bearing assemblies including bearing members and separator elements between the bearing members, the separator elements being of less diameter than the bore in said sheaves, so that the sheaves can be assembled on and removed from said shaft without disturbing the roller bearing assemblies on said shaft, and means extending through the shaft for lubricating said roller bearing assemblies.

13. In a block, the combination of a base structure, a shaft mounted across the base structure, a plurality of sheaves journaled on said shaft within the base structure, cross-over beams across said base structure parallel with said shaft, a cross-over shaft spanned between the cross-over beams and secured thereto, a cross-over sheave journaled on said shaft in a plane substantially tangent to the periphery of the rst said sheaves.

14. In a drilling rig, the combination of a crown block, including a main shaft, a plurality of main sheaves journaled on the main shaft, a cross-over shaft journaled above the main shaft, and extending across the main shaft, a cross-over sheave mounted on each end of the cross-over shaft in planes substantially tangent to the peripheries of the main sheaves, a traveling block having a plurality of sheaves rotatable on axes substantially parallel with the main shaft, and a line reeved between said sheaves first over one of said crossover sheaves, then under one end sheave of the traveling block, then over the other cross-over sheave, then under the sheave at the other end of the traveling block, then over one of the main sheaves, and then reeved progressively under and over the sheaves of the traveling block and crown block, respectively, from end to end of said traveling block and crown block.

15. In a block, the combination of a main shaft, a plurality of sheaves journaled on said main shaft, a cross-over shaft spanned above the periphery of the main sheaves, and extending across the main shaft, and a plurality of cross-over sheaves mounted on the cross-over shaft in planes substantially tangent to the peripheries of the main sheaves.

16. In a block, the combination of a base structure, a main shaft supported by said base stmoture, a plurality of casing line sheaves journaled on said shaft, cross-over supports mounted on said base structure parallel to the main shaft and beyond the periphery of said sheaves, a crossover shaft spanned between the cross-over supports and secured thereto, a cross-over sheave journaled on each end of said shaft on the inside and adjacent said supports, the casing line sheaves mounted on the main shaft being equally spaced axially of the shaft, the approximate spacing of said sheaves being determined by dividing the diameter of the cross-over sheave by a factor equal to one plus the number of casing line sheaves on said main shaft.

FORREST J. YOUNG. JOHN D. SPALDING.

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