Abstract:
A wireline hay pulley has a support with front and back plates extending therefrom. A sheave disposed between the plates can rotate on an axle. The front plate is affixed to the support, while the back plate is removably connected to the support. The front plate has a round opening in which an eccentric bushing on the axle can rotate. When the back plate is disconnected from the support, the back plate can turn the axle fixed in a slotted opening. An eccentric bushing on the axle rotates in an opening of the front plate, thereby shifting the sheave away from the support. With the back plate moved away and the sheave shifted downward, an operator can readily rig up a wireline in the sheave&#39;s slot.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is filed concurrently with U.S. patent application Ser. No. ______, entitled “Adjustable Wireline Sheave for Stuffing Box,” which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    Sheaves are used to route a wireline between a stuffing box at a wellhead and a wireline unit. For example, one sheave mounts onto the stuffing box for guiding the wireline to and from the stuffing box. Another sheave referred to as a hay pulley or floor block is used to change the wireline&#39;s perpendicular direction from the stuffing box sheave to a horizontal direction toward the wireline unit. The hay pulley can be mounted lower on the wellhead below the stuffing box sheave so that side forces on the wellhead can be reduced from the routed wireline. Rigging up a wireline in the various sheaves at a wellhead can be time consuming for operators. Should any adjustments be needed, operators may also need to be able to adjust or fix the wireline rigging in a timely manner. 
       SUMMARY 
       [0003]    A wireline hay pulley can be used to guide a wireline between a wellhead and a wireline unit. The hay pulley has a top block or support with front and back plates extending therefrom. A sheave disposed between the plates can rotate on an axle that is held between the plates. The front plate is affixed to the top block, while the back plate is removably connected to the top block by movable pins. The front plate has a round opening in which an eccentric bushing on the axle can rotate, but the back plate has a slotted opening in which a detent end of the axle fits. When the back plate is disconnected from the top block by removing the pins that hold it, the back plate can be moved to turn the axle fixed in its slotted opening. The eccentric bushing of the axle then rotates in the opening of the front plate, thereby shifting the sheave and back plate connected to the axle away from the top block. With the back plate moved away from the top block and the sheave shifted away, an operator can readily rig up a wireline in the sheave&#39;s slot. 
         [0004]    The foregoing summary is not intended to summarize each potential embodiment or every aspect of the present disclosure. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIGS. 1A-1B  show elevational and perspective views of a front side of a hay pulley according to the present disclosure. 
           [0006]      FIGS. 2A-2B  show elevational and perspective views of a back side of the hay pulley. 
           [0007]      FIG. 3  shows an exploded view of the hay pulley. 
           [0008]      FIG. 4A  shows a front cross-section of the hay pulley revealing the sheave, guide wheels, and top block when the hay pulley is in the operating condition. 
           [0009]      FIG. 4B  shows a side cross-section of the hay pulley of  FIG. 4A . 
           [0010]      FIG. 4C  shows a detail of the side cross-section of  FIG. 4B . 
           [0011]      FIG. 5A  shows an elevational view of the hay pulley when the hay pulley is in the opened condition. 
           [0012]      FIG. 5B  shows a side cross-section of the hay pulley of  FIG. 5A . 
           [0013]      FIG. 5C  shows a detail of the side cross-section of  FIG. 5B . 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    A front view of a hay pulley  10  according to the present disclosure is shown in  FIGS. 1A-1B , and a back view of the hay pulley  10  is shown in  FIGS. 2A-2B . The hay pulley  10  can be used to guide a wireline for a wireline operation at a wellhead or for some other type of operation. Normally, the hay pulley  10  attaches to the wellhead below a sheave (not shown) at a stuffing box (not shown) on the wellhead. From this position, the hay pulley  10  guides the wireline between the stuffing box sheave and the wireline unit and reduces the lateral force that the wireline exerts on the wellhead. 
         [0015]    The hay pulley  10  has a sheave  20 , front and back plates  30 / 40 , an axle  50 , and a support or top block  70 . The sheave  20  can rotate on the axle  50  connected between the plates  30 / 40 . The top block  70  at the upper ends of the plates  30 / 40  connects to a clevis  90  used for hanging the pulley  10  during use. The top block  70  affixes to the front plate  30  using fasteners  33 . However, the back plate  40  fits within a channel  76  in the top block  70  and is held by internal components described below. Pins  37  connected to the front plate  30  but not the back plate  30  support guide wheels  35  near the sheave  20  for guiding a wireline (not shown) that can run in the sheave&#39;s slot  22 . 
         [0016]      FIGS. 1A through 2B  show the hay pulley  10  in an operating condition for guiding the wireline. This condition is also shown in the cross-sections of  FIGS. 4A-4C . During operation, the sheave  20  supported on the axle  50  has its periphery positioned near the bottom of the top block  70 , and the guide wheels  35  on the pins  37  fit partially into the sheave&#39;s slot  22  to hold the wireline therein. 
         [0017]    To facilitate rigging up the wireline in the sheave&#39;s slot  22 , however, the pulley&#39;s back plate  40  can be moved away from the top block  70 , and the sheave  20  itself can also be moved away from the top block  70  and guide wheels  35  so that additional space is provided for fitting the wireline in the slot  22 . As explained in more detail below, a retainer removably connects the back plate  40  to the top block  70 . The retainer can selectively engage the back plate  40  and hold it to the top block  70  for the operating condition, or the retainer can selectively disengage the back plate  40  so it can be moved to an opened condition. 
         [0018]    As shown in  FIGS. 1A-1B , the retainer has a handle  84  at the top block  70 . Movement of this handle  84  can selectively detach pins  80  that hold the back plate  40  in the top block&#39;s rear channel  76 . When a lock mechanism  86  is moved, for example, an operator can pull the handle  84  outward from the front plate  30 , releasing the pins  80  from the back plate  40 . Once freed, the back plate  40  can be rotated away from the top block  70  so that the pulley  10  has an opened condition. 
         [0019]    Such an opened condition is best shown in  FIGS. 5A-5C . In the opened condition, the back plate  40  is freed from the movable pins  80  in the top block  70  by the pulling of the handle  84 . Being freed, the back plate  40  can be moved and can turn the axle  50 . The rotating axle  50  then eccentrically shifts the sheave  20  downward away from the top block  70  and the guide wheels  35 , and the shifted sheave  20  allows operators to install or remove the wireline in the sheave&#39;s slot  22 . All the while, the hay pulley  10  can remain hanging on the clevis  90 . 
         [0020]    Turning to  FIG. 3  showing additional details of the hay pulley  10 , discussion now turns to how the back plate  40  is held and released from the top block  70  and how the sheave  20  can shift away from the guide wheels  35  when the back plate  40  is moved out of the way. As shown, the top block  70  fastens to the front plate  30  using various fasteners  33 . A fastener  92  passes through an opening  72  in the top block  70 , and the clevis  90  fastens to this fastener  92 . 
         [0021]    For the axle  50 , an eccentric bushing  52  fits on a first end  62  of a shaft  60 , and the bushing  52  positions in a round opening  32  in the front plate  30 . A cotter pin type fastener and washer assembly  56  then attaches to the shaft&#39;s first end  62 , holding it to the plate  30  but allowing it to turn in the opening  32 . A bearing assembly  54  slips onto the shaft  60 , and a central opening  24  in the sheave  20  fits onto the bearing assembly  54  so the sheave  20  can rotate thereon. 
         [0022]    Guide wheels  35  fit onto pins  37 , and ends of these pins  37  connect to holes  36  in the front plate  30 . The back plate  40  is then positioned on the axle  50  by inserting the shaft&#39;s second end  64  into a contoured opening  42  in the back plate  40  and fastening it to a bolt  58  or the like. When an upper end of the back plate  40  is fit into the top block&#39;s channel  70 , distal ends of the pins  37  for the guide wheels  35  do not connect to the back plate  40 . 
         [0023]    Inside the top block  70 , pins  80  having springs  82  disposed thereon position into side holes  74  in the top block  70 . Proximal ends of these pins  80  pass through openings  34  in the front plate  30  and attach to the pulling handle  84  outside the plate  30 . Distal ends of the movable pins  80  fit into openings  44  in the back plate  40  so that the pins  80  can hold the end of the back plate  40  in the top block&#39;s channel  76 . The lock  86  that connects to the front plate  30  can be moved relative to the handle  30  to selectively engage a shoulder on one of the pins  80  and to prevent the pins  80  from being moved by the handle  84 . 
         [0024]    Returning to additional details of the shaft  60 , the shaft&#39;s second end  64  has a detent that fits into the back plate&#39;s opening  42  with a corresponding contour so the shaft  60  is prevented from rotating in the opening  42 . However, rotation of the back plate  40  relative to the top block  70  turns the shaft  60  of the axle  50 . At its other end  62 , the shaft  60  has keys  63  next to a lip. These keys  63  fit into a corresponding opening  53  in the eccentric bushing  52 . Therefore, the bushing  52  turns with the shaft  60  and rotates in the round opening  32  in the front plate  30  when turned. 
         [0025]    When the back plate  40  is unlocked from the top block  70  and then rotated to the opened condition (e.g.,  FIG. 5A ), the back plate  40  rotates the shaft  60  carrying the sheave  20 . The rotating shaft  60  turns the eccentric bushing  52  in the front plate&#39;s round opening  32 . As the shaft  60  turns eccentrically with the bushing  52 , both the back plate  40  and sheave  20  drop clear of the top block  70  until reaching the opened condition shown in  FIG. 5A . As a result, the rotated back plate  40  is moved out of the way of the top block  70  allowing an operator to rig up the wireline on the sheave  20 , and the sheave  20  dropped down from the top block  70  gives the operator additional space to rig up the wireline in the sheave&#39;s slot  22 . 
         [0026]    Although shown as having the separate eccentric bushing  52  disposed on the shaft  60 , it will be appreciated that an axle for the disclosed hay pulley  10  can have such an eccentric bushing integrally formed on the axle for fitting into a round opening of the front plate  30 . In addition, although the shaft  60  has the detent end  64  fitting into the back plate&#39;s contoured opening  42  so that turning of the back plate  40  rotates the shaft  60 , other types of connections could be used. 
         [0027]    The foregoing description of preferred and other embodiments is not intended to limit or restrict the scope or applicability of the inventive concepts conceived of by the Applicants. In exchange for disclosing the inventive concepts contained herein, the Applicants desire all patent rights afforded by the appended claims. Therefore, it is intended that the appended claims include all modifications and alterations to the full extent that they come within the scope of the following claims or the equivalents thereof.