FR2584451A1 - - Google Patents

Abstract

A DRILLING APPARATUS OF THE TYPE WITH A DRILL MAST 12 IS EQUIPPED WITH A TRANSFER ARM 14 MOVABLE, BY ROTATION AROUND A FIRST AXIS 20, BETWEEN A HIGH POSITION IN ALIGNMENT WITH THE MAST AND A LOW POSITION PARALLEL TO THE GROUND. THE CONTROL SYSTEM FOR RAISING AND LOWERING THE ARM 14 HAS A FIXED SUPPORT POINT 22 WHICH IS SPACED FROM THE FIRST AXLE 20. A ROD 24 OF FIXED LENGTH IS ARTICULATED TO THE ARM 14 AROUND A SECOND AXLE 30 WHICH IS SPACED FROM THE FIRST SHAFT 20. A FIRST HYDRAULIC CYLINDER WITH ONE STAGE 32 IS ARTICULATED BETWEEN THE OUTER END 28 OF THE CONNECTING ROD 24 AND THE TRANSFER ARM 14. A SECOND HYDRAULIC CYLINDER AT ONE STAGE 38 IS ARTICULATED BETWEEN THE OUTER END OF THE CONNECTING ROD 24 AND THE SUPPORT POINT 22.

Description

The present invention relates to an improved apparatus for lifting and

  lower a transfer arm into a drilling rig. More particularly, it relates to a control device for a rigid transfer arm, mounted to be raised and lowered around a first axis located near or on a mast.

  drilling device, a device used to move the arm between a position

  low position near the ground and a high position in alignment with the mast, the displacement between these two positions of the arm corresponding to a rotational movement on an arc of about 90 around the

first axis.

  US Patent 4,407,629, to the applicant, discloses a drilling rig having significant economic advantages using a lifting and lowering transfer arm which is mounted on or near the drilling mast and is used to move tubular sounding elements between a low position in alignment with a rod park and a position

  high in alignment with the drilling axis of the drilling rig.

  Such transfer arms greatly increase work efficiency by reducing the manpower and time required

  to assemble and disassemble the drill rods.

  The tubular elements for drilling and casing are

  stored in rod parks at the drilling location.

  It is therefore advantageous to design the transfer arm so that

  that it can load and unload direct tubular elements-

  lying on and from such rod parks, limiting movement

  vertical tubular elements to a minimum. For this reason, it is highly desirable to design the

  control of the transfer arm so that the tubular elements

  laires can be transferred, between the pens and the arm, at a relatively low level, typically at a height of the order of

1.50 m to 1.75 m above the ground.

  A solution of the prior art provides for the use of hydraulic cylinders with three or four stages to raise and lower the transfer arm. However, such multi-stage cylinders have several significant drawbacks. Firstly, it has been found that such cylinders have a relatively short service life in many applications. Multi-stage cylinders are typically designed for intermittent service, not continuous service, and the continuous operations that are necessary to raise and lower drill pipes to change drill bits, fish tools, and so on, can represent excessive loads. . In addition, multi-stage cylinders are not well suited to withstand lateral loads of the type that inevitably occur when heavy drill collars

  are rolled in the tube clamps mounted on the transfer arm.

  In addition, multi-stage cylinders expose relatively large areas coming into contact with hydraulic fluid, which can cause problems when these areas are exposed to sludge

  that fall from tubular drilling elements when they

  these are transferred between the drill pipe and the rod parks.

  Multi-stage cylinders also pose problems of

  ordered. Indeed, such a jack raises the arm relatively slowly-

  ment during the first 10 or 20 of the arm lifting movement; on the other hand, for a given flow rate of the hydraulic fluid, the angular speed of the transfer arm increases rapidly when it approaches the vertical position. It thus becomes difficult to decelerate the arm gently when approaching La

high position.

  A second possible solution for raising and lowering a transfer arm is shown in the aforementioned US Patent 4,407,629. The system described in this patent uses an articulated control mechanism with a single-stage hydraulic cylinder and two rods of fixed length. This solution also has

  disadvantages with regard to the smooth setting of the dece-

  leration and speed of the transfer arm when approaching the

high position.

  The system described in the aforementioned patent uses a relatively large angle of rotation of the transfer arm for a relatively small extension of the hydraulic cylinder when the arm is close. from the vertical. For this reason, the precise adjustment or control of the deceleration and speed of the arm is

difficult to obtain.

  The invention provides an improved control device for a transfer arm, of the type indicated at the start, which uses robust and durable hydraulic cylinders, which is compact and allows better control of the speed and acceleration of the

transfer arm.

  According to the invention, a control device as defined at the start has a fixed support point relative to the mast and spaced from the first axis. A rod of fixed length is articulated by a first end to the transfer arm, around a second axis

  spaced from the first axis, and has a second end or end

  outdoor moth. A first cylinder, such as a single-stage hydraulic cylinder, is articulated by one end on the outer end of the connecting rod and by the other end on the transfer arm. A second cylinder, such as a single-stage hydraulic cylinder, is articulated by one end on the outer end of the connecting rod and by the other end

on the fulcrum.

  The device according to the invention brings important advantages. Because it can be fitted with single-stage cylinders instead of multi-stage cylinders, it constitutes an articulated control mechanism which is robust and durable, which is well suited to withstand lateral loads and which exhibits only one

  hydaulic surface - coming into contact with hydraulic fluid -

  relatively small to soiling. The mechanism according to the invention is compact and is excellent for lowering the transfer arm to a point where this arm extends parallel to a small height above the ground. The provision of two cylinders allows better control of the speed and acceleration of the arm when it approaches the high position in alignment with the drilling mast. This improved control makes the mechanism according to the invention suitable for rapid and fully automatic operation of the transfer arm. Other characteristics and advantages of the invention

  will emerge more clearly from the following description of a

  nonlimiting exemplary embodiment, as well as the attached drawings, in which:

  - Figure 1 is a side elevational view of an apparatus

  drilling rig using a currently preferred embodiment

  re of the control device according to the invention; the transfer arm being shown in the high position; and - Figures 2 and 3 are similar views showing the transfer arm in an intermediate position respectively in

low position.

  Drawings represent parts - of interest

  for the present description - of a drilling rig 10

  comprising a drilling mast 12 and a transfer arm 14. The arm 14 can be raised and lowered as a rigid unit, by rotation about a first axis 20 which is fixed relative to the mast 12. The transfer arm 14 carries two tube clamps 16 which are spaced from each other and serve to fix tubular sounding elements to the arm 14 when the latter is used to raise tubular sounding elements from a rod park until they are aligned with the drill pipe and for lowering such elements from the position in alignment with the drill pipe

to the rod park.

  It should be noted that the control device according to the

  vention is suitable for a wide variety of drilling rigs and transfer arms, the drilling rig 10 and the arm 14 having only been shown for the explanation of an embodiment of the invention. For example, the control device according to the invention can easily be adapted to be used with oblique drilling where the mast 12 is not oriented vertically and where the angle between the extreme positions of the transfer arm will generally be different from 90 . Likewise, the transfer arm 14 can be produced in the form of a monocoque veil construction.

  thin freestanding, or in the form of a lattice construction.

  As the invention is not linked to a particular structure of the transfer arm 14 or of the mast 12, the features of this arm and of this mast will not be described in more detail here. An example of a suitable transfer arm 14 is described in more detail in the

  U.S. Patent 4,407,629 previously cited.

  According to the invention, a support point 22 is rigidly connected

  to the drilling rig 10 at a point spaced from the first axis

  20. a rod 24 of fixed length, having a first end

  tee 26 and a second end or outer end 28, is articulated to the transfer arm 14 around a second axis 30 which is

spaced from the first axis 20.

  A first cylinder 32, for example a conventional hydraulic cylinder with one stage, has a first end 34 which is articulated on the transfer arm 14 and a second end 36 which is articulated

  on the outer end 28 of the connecting rod 24.

  The control device according to the invention comprises a second cylinder 38, which can also be constituted by a conventional hydraulic cylinder with one stage for example, which is articulated by a first end 40 on the fulcrum 22 and by its second end

  42 on the outer end 28 of the connecting rod 24.

  The two jacks cooperate with the connecting rod 24 to raise and lower the transfer arm 14 smoothly and in an easily controllable manner. Figure 3 shows the arm 14 in its low position, o

  it extends parallel to the ground surface.

  To raise the transfer arm 14, hydraulic liquid

  The pressurized liquid is sent to the two jacks 32, 38. As the first jack 32 works with a more favorable lever arm than the second jack 38 when the arm 14 is in the low position, the first jack 32 extends before the second , thus raising arm 14

  at the intermediate position shown in Figure 2.

  During the lifting of the arm, the first cylinder 32 extends completely, as shown in FIG. 2, and the second cylinder 38 begins to extend thereafter. The second cylinder continues its extension until the arm 14 occupies the high position visible in FIG. I; in this position, the two cylinders will generally be fully extended. Even when the arm 14 approaches this high position, the angular orientation of the second cylinder 38 is such that this cylinder allows excellent control of the acceleration and the speed of the arm. For this reason, the mechanism shown in Figures 1 to 3 allows the operation

  precise, fast and fully automatic transfer arm 14.

  As can be seen in the drawings, in the currently preferred embodiment, the second axis 30 and the other end

  articulated 34 of the first cylinder 32 are located on the upper side -

  in the lowered position for example - of the transfer arm 14.

  It can also be seen that, in this embodiment, the second cylinder 38 is approximately parallel to the arm 14 and to the ground when the

arm is in the down position.

  When it is desired to lower the transfer arm 14, the sequence described above proceeds in reverse. It may be desirable in certain applications to provide, if necessary, separate valves for controlling the admission of pressurized hydraulic fluid into the two jacks 32, 38 so that the extension and

  the retraction of the cylinders is carried out in the desired order.

  However, the use of separate valves can be avoided in many applications since, generally, the location, arrangement and dimensions of the cylinders 32, 38 will be chosen from

  such that these two cylinders extend and retract automatically

  matically in the desired order, as described in the foregoing.

  An important feature of the mechanism according to the invention

  tion is that the axis 30 is aspached from the axis 20. In the embodiment shown, the axis 30 is located approximately halfway between the axis 20 and the articulated end 34 of the jack 32 being opposite its articulated end on the connecting rod 24. The Applicant has found that a compact mechanism is thus obtained allowing a

  particularly favorable control of speed and acceleration

  tion of the transfer arm 14. This stems from the fact that, when the assembly is carried out as shown in the drawings, the connecting rod 24

  raises the upper end 42 of the jack 38 to an excellent position

  tion for perfect control of the final acceleration of the arm 14

  in its approach to the high position shown in Figure 1.

  It follows from the above that the invention provides an improved control or positioning system for a transfer arm, allowing excellent control of speed and acceleration, which is durable and well suited to withstand

  damage which may result from side loads

  which can be easily integrated into an entire system.

  automatic high speed control of the transfer arm

  fert. Of course, it will be understood that many changes and modifications are possible, compared to the embodiment.

  preferred which has just been described, without departing from the scope of the invention

  tion. For example, the cylinders 32, 38 and the connecting rod 24 can be used as single elements, as shown in the

  drawings, but it is also possible to provide two identical sets

  ticks, each comprising two jacks and a connecting rod, a clearance on each side of the transfer arm 14. Also as described in this

  above, the structure of the arm itself can be varied widely-

  ment, depending on the particular application, and the same applies to the structure of the drilling rig and the drilling mast 12. The invention is therefore by no means limited to the embodiments described and the skilled in the art can bring various

  modifications without departing from its framework.

Claims (6)

  1. Control device for a rigid transfer arm, mounted to be raised and lowered around a first axis located near or on a drilling mast, the control device serving to move the arm between a low position close to the ground and a high position in alignment with the mast, moving the   arm between these two positions corresponding to a rotational movement   tion on an arc which is in particular about 90 around the first axis, characterized in that it comprises: a fulcrum (22) fixed relative to the mast (12) and spaced from the first axis (20); a rod (24) of fixed length, which is articulated by a first end to the transfer arm (14) around a second axis (30) spaced from the first axis (20) and which has a second end or outer end (28 ); a first jack (32) articulated by one end on the outer end of the connecting rod (24) and by the other end on the transfer arm; and a second jack (38) articulated by one end on the outer end of the connecting rod (24) and by the other end on the fulcrum (22); the first and second cylinders (32, 38) cooperating with the   connecting rod (24) for moving the transfer arm (14) between the positions   high and low, so that the two cylinders are extended to the high position of the transfer arm, the second cylinder (38) being oriented approximately parallel to the transfer arm and the   ground surface when the transfer arm is in the down position.   2. Device according to claim 1, wherein each   cylinders consists of a single-stage hydraulic cylinder.   3. Device according to claim 1 or 2, wherein the second axis (30) and the other articulated end (34) of the first cylinder   (32) are located on the upper side of the transfer arm (14).   4. Device according to any one of claims 1   to 3, further comprising a device for sending a hydraulic fluid under pressure simultaneously to the two jacks (32, 38) When - The transfer arm (14) occupies the low position, in view   lifting the arm to the high position.   5. Device according to claim 4, in which the two cylinders are arranged, arranged and dimensioned so that the first cylinder (32) extends before the second cylinder (38) when hydraulic fluid under pressure is sent simultaneously to   two cylinders when the transfer arm (14) is in the low position.   6. Device according to any one of claims 1   - at 5, in which the second cylinder (38) is oriented approximately parallel to the transfer arm (14) and to the ground surface   when the transfer arm is in the low position.