US 3804168 A
In a wire line cable system for use in drilling wells, a sheave is supported above a packoff on the upper end of drill pipe permit movement of wire line into the drill pipe. A socket is positioned below the sheave and has a bore for receiving the wire line. A clamp is secured to wire line below the socket and as the wire line moves into the packoff, the clamp engages the socket to prevent further movement of the wire line into the drill pipe.
Description (OCR text may contain errors)
tp nii United States Patent [191 Marshall et al.
WIRE LINE CLAMP Inventors: Gailen D. Marshal]; Clarence H.
Myska, both of Houston, Tex.
Assignee: Sperry-Sun Well Surveying Company, Sugar Land, Tex.
Filed: June 8, 1972 Appl. No.: 263,725
US. Cl 166/250, 175/45, 175/214 Int. Cl E2lb 47/022 Field of Search 166/75, 77, 315, 64, 65, 166/66, 72, 311, 250; 175/162, 214, 103, 45; 24/l14.5, J, 136 R, 136 L, 123 R; 114/199; 182/150; 254/136 R, CE, 139, 145, 148, 167, 168, 33/136 References Cited UNITED STATES PATENTS 4/1960 Vebelhoer 254/139 X 2/1886 Winter 24/123 R X Primary Examiner-Joseph H. McGlynn Assistant Examiner-Richard P. Tremblay Attorney, Agent, or Firm-George L. Church; Donald R. Johnson; John E. Holder [5 7 ABSTRACT In a wire line cable system for use in drilling wells, a sheave is supported above a packoff on the upper end of drill pipe permit movement of wire line into the drill pipe. A socket is positioned below the sheave and has a bore for receiving the wire line. A clamp is secured to wire line below the socket and as the wire line moves into the packoff, the clamp engages the socket to prevent further movement of the wire line into the drill pipe.
9 Claims, 3 Drawing Figures PM'ENTEH APR 16 I974 FIC33 FIG. 2
WIRE LINE CLAMP BACKGROUND OF THE INVENTION This invention relates to a wire line clamp, and more particularly to an apparatus for clamping a wire line against movement into a drill pipe during a drilling operation.
During the drilling of boreholes into the earth, it is often desirable to determine characteristics of borehole conditions, such as for example, the attitude of the hole when directional drilling, or other such information while the drilling operation is taking place. This is usually accomplished by passing an instrument into the drill pipe and seating it therein so that downhole parameters can be detected for transmittal to the surface. Such information transmittal to the surface is normally accomplished by means of a cable which is attached to the instrument and passes through the bore of the drill pipe to the surface where it is connected to a device for recording instrument measurements.
A common use for such apparatus is in the drilling of directional wells. With the advent of increased production in offshore areas, the use of directionally drilled wells is becoming more common because of the economics which can be derived from constructing a large drilling platform which is securedto the ocean floor and drilling a multiplicity of wells therefrom. Because of the number of wells which are drilled from a single platform it is necessary to drill the holes laterally away from the platform and in so doing petroleum reservoirs may be penetrated at distances laterally spaced from the platform. It is readily seen how important the maintenance of direction and dip of the borehole is, in order to penetrate particular formations at predetermined depths, and thereby intersect the desired petroleum reservoirs.
One technique for obtaining such information as to the orientation of a borehole is to pass an instrument into the drill stem by means of a conductor cable to provide continuous directional information to the surface during the drilling operation. Such a system is described in greater detail in copending application Ser. No. 86,877 now US. Pat. No. 3,7l8,l94 which is assigned to the same assignor as the present application.
It is common in such directional drilling operations to use a mud motor or turbine for rotating the drill within the borehole. Such a device requires the continuous circulation of drilling fluids through the motor to provide the power for turning the drill. Therefore, it is essential that a constant flow of drilling fluids be maintained through the system even while an instrument is positioned within the drill stem. As a result, continuous pressure is being applied in a downward direction to the conductor cable which is connected to the instrument, therefore tending to pull the conductor or wire line cable into the drill pipe. In order to obviate this problem it is common to use a line wiper or pack-off device at the upper end of the drill string where the wire line conductor enters the pipe. Such devices are commonly arranged to apply a hydraulic force about the wire line conductor to hole it in place and consequently prevent its being stripped into the well due to forces being applied to the cable. In addition, it is a common expedient in such operations, after the instrument has been located in a seat at the bottom of the drill string, to place a clamp on the conductor cable above the pack-off line wiper and thereafter pass the cable into the pipe until the clamp has seated on top of the line wiper. This in turn provides a positive brake against further movement of wire line into the drill pipe. The procedure heretofore for setting such clamp has been to position the instrument in its seat at the bottom of the drill stem, then pass an additional few feet of cable into the drill pipe. Thereafter hydraulic pressue is applied to the line wiper at the upper end of the drill stem to immobilize the movement of cable. At this point, one of the drilling personnel has positioned himself in the derrick super structure at a location adjacent the upper end of the drill string to manually position the clamp on the wire line conductor just above the line wiper. Such use of drilling personnel exposes them to the hazards of climbing about in the derrick super structure.
It is therefore an object of the present invention to provide a new and improved method and apparatus for clamping a wire line conductor against movement during a drilling operation.
SUMMARY OF THE INVENTION With this and other objects in view, the present invention contemplates a drilling system utilizing a wire line conductor and having a clamp system which permits all manual operations related thereto to take place on the derrick floor. The system includes a sheave which is positioned above a liner wiper at the upper end of the drill string anda socket which is positioned below the sheave on the opposite side of the sheave from the line wiper. Thus, cable emerging from the upper end of the drill string passes through the line wiper around the sheave and down through the socket. This cable then extends downwardly to another sheave on the derrick floor and onto a take up drum. With this arrangement it is possible to place a clamp on the wire line conductor at a position on the derrick floor and thereafter pass cable into the pipe until the clamp seats within the socket near the upper end of the drill string. This provides a positive stop to prevent passage of cable into the drill pipe during a drilling operation.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a schematic view of a drilling platform and derrick together with the upper end of the drill pipe and a system for passing a wire line conductor into the upper end of the pipe, and
FIG. 2 is a detailed view of an apparatus in conjunction with the present invention for clamping a wire line against movement into a drill pipe.
FIG. 3 is a detailed view of the wireline clamp socket shown in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIG. 1 of the drawings, a drilling platform is shown having a derrick structure and equipment supported from the derrick which is used in a directional drilling operation. In the simplified illustration in FIG. 1 equipment normally associated with the support of the drill pipe is not shown for the convenience of illustrating the more pertinent parts of the present invention. However, in such an illustration the drill string, including the bit, is supported by a drilling head which in turn suspends from a hook, traveling block, wire line and crown block on top of the derrick mask.
In FIG. 1 a drilling head 1 1 is shown positioned at the top of the drill string 12 which in turn passes through the platform floor 13 and downwardly into the borehole which is not shown. The drilling head includes a circulating head 14 and gooseneck 16 which are arranged for connection with a hose or the like for passing drilling fluid from pumps (not shown) into the drill string. Above the circulating head is a wire line packoff 17 which is also sometimes referred to as a line wiper. The line wiper is arranged to be disassembled so that the cable or conductor line may be passed therethrough whereupon it is reassembled to enclose the conductor cable. The unit is normally hydraulically actuated by means of a hydraulic line (not shown) which is connected to a hand pump. The hand pump provides hydraulic pressure which squeezes portions of the line wiper about the line and thereby provides a pressure seal around the line at the upper end of the drill string. The top section of the drill pipe 18 is connected at its upper end to the circulating head 14 and below to pipe sections extending downwardly to the bottom of the bore hole.
Referring also to FIG. 2, a sheave support assembly 19 is shown connected to the line wiper 17 and has a vertically extending arm 21 with a sheave housing 22 positioned at its upper end. The sheave housing has a guard 23 and an axle 24 for supporting a sheave wheel 26. The sheave wheel is grooved about its periphery to provide a seat for the conductor cable 27 which is passed around the sheave. A bracket 28 extends outwardly from the vertical arm 21, with a wire line clamp socket 29 being fixed to the bracket. The socket has a vertical bore portion 31 therethrough which is aligned with the outer edge of the sheave 26. The inner edge of the sheave is positioned directly over the center portion of the line wiper 17. The socket has a spiral slot 32 formed in its wall (see FIG. 3) to permit the insertion of a cable into the bore 31 of the socket 29.
Referring again to FIG. 1, another sheave 33 is placed near the floor of the platform and is supported by chains 34 or the like at a position on the platform opposite a powered cable take-up reel 36. The take-up reel 36, floor sheave 33 and upper sheave 26 are so ar ranged that the conductor cable 27 may be passed from the take-up reel around the lower sheave, through the wire line socket, and over the upper sheave.
A wire line clamp 37 shown in FIG. 2, may be positioned on the conductor cable and tightened thereabout by means of screws 38 or the like so that it is securely fastened at one position on the cable. The clamp may be arranged in two parts so that it can be assembled over the cable and then tightened thereon. The clamp has a tapered portion 39 at its upper end which is shaped to be matingly received in a beveled seat 41 in the lower end of the socket bore 31.
In the operation in the apparatus described above, the following procedure is followed for running a conductor cable into a drill pipe for use during a drilling operation:
The floor sheave 33 is secured to a structural member of the derrick in line with the wire line reel 36 and the top of the borehole. The drilling head 11 is then assembled to the single joint of drill pipe 18. The upper sheave support assembly 19 is placed on the line wiper body. The well tool (not shown) which is to be supported by the conductor cable 27 is then lifted up and inserted through the upper end of the line wiper 17 into the upper section 18 of drill pipe. The cable is then reeled out until the tool is resting at the bottom of the section 18 of the drill pipe. The line wiper 17 is then assembled about the cable and the hydraulic hose is secured to the line wiper. The cable 27 is then threaded over the top of the sheave 26 and the cable guard 23 placed over the sheave. Pressure is then applied to the line wiper to hold the cable immobile. Next, the drilling assembly and upper section of pipe are lifted by means of the elevators, whereupon the lower end of drill pipe 18 is connected to the upper end of the drill string 12. Pressure is then released on the hydraulic line wiper and the tool is lowered into the hole on the cable.
When the reading on a wire line odometer indicates that the tool is near the lower end of the drill string, the speed of descending into the hole is slowed until the tool has seated at the bottom of the drill string. When the tool is seated, the seating depth is determined. Then approximately five feet of slack cable are passed into the drill string. At this time the reading of the cable measuring odometer is noted. In the meantime the distance from the derrick floor 13 to the wire line clamp socket 29 has been predetermined. An amount of cable equal to this distance between the wire line clamp socket and the rig floor is pulled out of the drill pipe be means of the reel 36. The wire line clamp 37 is then secured to the cable at the rig floor level. The cable is then let back into the dril pipe until the tapered portion 39 on the wire line clamp 37 engages the seat 41 on the wire line clamp socket 29. Hydraulic pressure is then applied to the line wiper, and at this point drilling may occur.
It is readily seen that various forms of clamp and its arrangement with respect to the wire line may be made. However, the important feature of the present invention is that it allows for a safe operation in the e of a wire line clamp. Therefore, while a particular embodiment of the present invention has been shown and described, it is apparent that changes and modifications may be made without departing from this invention in its broader aspects and the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.
What is claimed is: i
1. In a cable system for use in drilling wells, means for clamping the cable against movement into a drill pipe, having a cable pack-off at its upper end, which means comprises: support means attached to the pack-off; sheave means attached to the pack-off; and stop means on said support means, said sheave means being arranged so that one side is positioned over the pick-off and the other side is positioned over said stop means, with said stop means having an opening for receiving the cable therethrough.
2. The apparatus of claim 1 wherein the opening in said stop means is arranged to matingly receive a clamp positioned on the cable.
3. The apparatus of claim 2 wherein the opening in said stop means has a tapered seat for receiving a complementary tapered surface on the cable clamp.
4. The apparatus of claim 1 wherein said stop means is a cylindrical member having a slot in the wall thereof to permit convenient insertion of the cable into the bore of said stop means.
5. The apparatus of claim 4 wherein said slot is on a bias.
6. A method for clamping a cable against movement beyond a desired point into a string of pipe having a cable pack-off at its upper end including the steps of: positioning a sheave above the pack-off so that one end is aligned with the pack-off; positioning a stop member below the sheave so that a vertical bore in the stop member is in alignment with the other edge of the sheave, passing a cable through the bore of the stop member, around the sheave and into the pack-off; and placing a clamp on the cable below the stop member and intermediate the ends of the cable such that the clamp is positioned on the cable for engagement with the stop member as the cable passes into the pack-off to stop the cable from moving into the pipe beyond the desired depth.
7. The method of claim 5 and further including the step of placing the cable through a vertical opening in the wall of the stop member to position the cable within its bore.
8. A method for clamping a cable against movement into a string of pipe suspended into a borehole from a well platform including the steps of: passing a cable from a reel on the platform through an opening in a stop member, around a sheave and into the string of pipe; lowering the cable into the pipe to its desired position; determining the distance from the floor of the well platform to the stop member; operating the reel to withdraw an amount of cable substantially equal to such distance from the pipe; securing a clamp to the cable at the floor of the platform, said clamp having a portion larger than the opening in the stop member; and again passing the cable into the pipe to its desired position, whereupon the clamp will engage the stop member.
9. A clamping system for use with a well drilling apparatus having a derrick on a platform supporting a drill pipe and a cable pack-off at the upper end of the drill pipe, which system comprises: support means attached to the pack-off,first sheave means attached to the support means such that a first side of the sheave means is positioned over the pack-off; stop means having a central opening attached to the support means such that the stop means is under a second side of the sheave means; a cable entering the drill pipe and packoff, and extending over the sheave means and through the opening of the stop means; a clamp attached to the cable and disposed to engage the stop means; second sheave means on the platform which engages the cable below the stop means; and a take-up reel on the platform and attached to the cable.