US2670925A - Automatic control for keeping predetermined weight on a drilling bit - Google Patents

Description

March 2, 1954 J. w. DES CHAMPS AUTOMATIC CONTROL FOR KEEPING PREDETERMINED WEIGHT ON A DRILLING BIT 3 Sheets-Sheet 1 Filed Nov. 3, 1951 I INVENTOR. fi/vis /4 flew/249m: BY

W m \f- 74/7/1457 March 2, 1954 w DES c Ps 2,670,925

AUTOMATIC CONTROL FUR KEEPING PREDETERMINED WEIGHT ON A DRILLING BIT Filed Nov. 3, 1951 3 Sheets-Sheet 2 IN V EN TOR. Ty/15'; Mia's [yaw/=5 Ma 1954 J w. DES CHAMPS AUTOMATIC CON' IROL FOR KEEPING PREDETERMINEID WEIGHT ON A DRILLING BIT Filed NOV. 5, 1951 3 Sheets-Sheet 5 IN VEN TOR.

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Patented Mar. 2, 1954 I AUTOMATIC CONTROL FOR KEEPING PRE DETERMINED WEIGHT ON A DRILLING BIT James W. Des Champs, Buenos Aires, Argentina Application November 3, 1951, Serial No. 254,735

7 Claims. (01. 254 17s) The invention herein disclosed relates to well drilling operations and particularly to the drilling of deep oil wells where there is the need for keeping as nearly as possible, a predetermined weight on the drill to maintain the most effective drilling conditions.

The general practice has been for the driller to observe a weight indicator on the deadline and to release the brakes on the spooling drum so as to lower the bit at a rate showing approximately the same load on the weight indicator. As the driller cannot watch this indicator constantly or coordinate his control actions accordingly, such methods are at best poor approximations of the control desired.

Accordingly, it is a purpose of the present invention to provide an automatic form of control which will constantly measure the load and immediately make the necessary corrections to maintain a predetermined desired Weight on the drill.

It is a further purpose of the invention to provide this automatic control in a simple, substantial form suited to oil field operations, consisting of few sturdy parts which will not get out of order under oil field operating conditions, which may be readily and easily mounted on and be connected with the drilling rig, which can be furnished at reasonable cost and which as a whole will be entirely practical and desirable for the purposes indicated.

Other objects and the novel features through which the purposes of the invention are attained are set forth or will appear in the course of the following specification.

The drawings accompanying and forming part of the specification illustrate certain present embodiments of the invention but it will be appreciated that structure and operation may be modified and changed as regards the immediate disclosure, all within the true intent and broad scope of the invention as hereinafter defined and claimed.

Fig. 1 in the drawings is an illustration of a rotary rig having the invention applied thereto;

Fig. 2 is a broken, part sectional and diagrammatic view showing the balance beam and appurtenant parts removed from the casing of the control instrument; 1

Fig. 3 is a diagrammatic View of the opposed motor control mechanism for the drawworks;

Fig. 4 is a diagrammatic view of a multiple leverage system for the balance beam;

Fig. 5 is a broken diagrammatic view of a 2 modification in which control is exercised by spooling the deadline on a separate winch.

In the general view, Fig. '1, there is shown a rotary rig of conventional design involving derrick I, draw works 8, rotary 9 and drill string l0 and bit ll suspended by traveling block l2 from crown block l3.

The automatic control mechanism is located at l4 on the floor of the derrick, connected wit and actuated by the deadline I5.

Fig. 2 shows how the deadline I5 is run down under and around guide sheaves I6, IT, to a clevis l8 swiveled at I!) to a beam 20 at one side of the supporting fulcrum 2|.

A weight 22 calculated to balance the deadline load is shiftable along the beam at the opposite side of the fulcrum by means of a screw shaft 23 which can be turned as by means of a hand crank 24 accessible at the end of the beam or by a reversible motor 25 mounted over the fulcrum portion of the beams A weight applying counter-balance 26 is shown slidably adjustable over the beam at the load applying side of the fulcrum, and this adjustable counter-weight is shown associated with 'a' scale 21 which may be calibrated in terms of tons loading on the bit.

The rocking movements of the beam occasioned by variations in the pull of the deadline caused by the changing penetrating effect of the bit, may be utilized to effect mechanical, electrical, hydraulic, compressed air, or other controls.

In the example shown in Fig. 1, an electric contact 28 on the top of the beam will engage stationary contact 29 on a bumper 30 to close one circuit on the lifting'movement, and similar contacts 3|, 32, be closed on the lowering movement of the beam.

The two circuits thus closed and opened may be utilized to efiect reverse movements of the balancing motor 25 which will shift the weight 22 to restore balance on the beam after efiecting a change in feed or,'as indicated'i'n Fig. 3, to energize one'of two reversely acting motors 33, 34, connected with a worm'35 in engagement with worm gear 36 on the spooling drum or other shaft 31 of the draw works.

Other electrical control devices may be actuated from the switches or switch contacts directly or indirectly actuated by'the beam.' In some instances only one of these'switches may be used and such switch 'o'r'switches maybe associated with other control equipment such as a Dynamatic brake or hydraulic or air actuated control equipment. 7

In Fig. 2 the end of the beam is shown as carrying an extension 38 for actuating the toggle 39 of an air controller 40 for draw works brakes or the like.

Fig. 4 shows how the beam may be actuated through a leverage system in the form of a lever 4| connected with the deadline at one end, fulcrumed at 42 and bearing at 43 at the opposite end on a secondary lever 44 pivoted at one end at 45 and connected at the opposite end through a pull link 46 with the beam at the loading side of the beam fulcrum 2|.

Necessary control connections will vary according to the particular control system employed.

Fig. 2 shows how with main switch 41 closed, circuit will be completed throughconnections 48, 49, to energize the reversible balancing motor in one direction when the beam closes the upper switch contacts 28, 29, and circuit be completed through connections 59, 49, to energiz this motor in the reverse direction when the beam closes circuit through the lower set of contacts 3!, 32.

In Fig. 3 a circuit arrangement is shown for controlling two motors 33, 34, directly or indirectly geared to the spooling drum for paying out or taking in cable as the need for adding or subtracting weight on the bit arises, as indicated by lifting or lowering movements of the beam end.

The upper switch contacts 28, 29, are here shown connected by wiring 5| and 52 with motor 33 and main switch 53, this switch and the motor connected with the supply circuit at 54, 55.

The lower control switch 3 l, 32, is shown connected by wiring 58, 51, with motor 34 and the double pole main switch 53, with connections completed'through wiring58 and 59 to opposite sides of the-line.

Mechanical, hydraulic, air or other operating connections maybe employed, th air valve indicated at 40, Fig. 2, operated by the end of the beam constituting one example of the same.

The main switch such as 41 in Fig. 2, or 53 in V Fig. 3, permits the automatic control to be shut off until drilling operations commence. Then on-the closing of this switch the beam may be balanced against the pull of the deadline by shifting the balance weight 22 by hand at 24 or through motor 25. After the load of the drill string and bit is balanced the counter-weight 25 may be shifted toward the deadline pull connection Hi to in efiect lighten the pull on the beam and apply control for adding weight to the bit; in other words, effect a lowering of the bit in the hole. By proper calibrations this loading effect may b indicated by the counter-weight scale 21, or other means may be employed for indicating actual weight on the bit.

This loading or weighting of the bit may be accomplishedalso 'by'shifting the balance weight 22 on the beam'and employing the balancing motor 25 to automatically shift the balancing weight as the need arises to apply less or more weight to the drill.

As another or different method of balancing the beam, the fulcrum for the beam may be made shiftable as by locating it on a block 50, Fig. 2, slidable in a slot orguideway 6| in the beam. This block-may carry an index or scale registrable with a-scale or index on the beam to show variations-in leverage ratios, weight or other values, to-aid the driller-in effecting desired fulcrum settings. These fulcrum adjustmentsmay be effected by screw or other forms of gearing providing the necessary leverage and power for accomplishing relative shifting of the fulcrum center. The trunnion mounting for the fulcrum is not shown but it will be appreciated that this is structurally capable of carrying the full loads that may be imposed on the beam.

The invention provides simple and effective means for automatically adding or subtracting weight on the bit directly and immediately as the need for such adjustments is sensed by the deadline. The equipment necessary for th purpose may be compact and small enough to be located on the derrick floor or other convenient, appropriate place, out of the way of other drilling equipment and operations.

Fig. 5 shows how the purposes of the invention maybe attained by spooling the end of the deadline IS on a separate drum 62 which may be controlled from the beam 20 and be driven one way .or the other by reversible motors or the like, in the same manner as disclosed in Fig. 3,

This construction has the advantage that the invention may be installed without making any changes in the draw works.

In this construction the loaded end of the supplementary bar 4| carries a sheave 63 over which th deadline is run to the drum. The control mechanism for the winch in both Figs. 4 and 5 may be like that shown in Figs. 1, 2 and 3. In all cases the deadline is directly or indirectly connected with the balancing beam, and the drum control mechanism is operated by this beam in accordance with actual load on the beam.

What is claimed is:

1. Automatic control apparatus for maintaining desired weight on thebit of a rotary drill having cable supporting the drill string and terminating in a deadline, and comprising a beam fulcrumed for balancing movement and equipped with means for effecting connection of the deadline therewith and whereby said beam will be subject to the pull of said deadline, means for balancing the-beam against the load of the drill string supported by the cabl and asserted by pull of the deadline on the beam, a counterweight adjustable on the beam to the effect of applying weight to the drill string and control mechanism operable by the beam for effecting weight loading or unloading of the drill string in accordance with the movements of said beam.

2. Automatic control apparatus for maintaining desired weight on the bit of a rotary drill having cable supporting the drill string and terminating in a deadline, and comprising a beam fulcrumed for balancing movements and equipped with means for effecting connection of the deadline therewith and whereby said beam will be subject to th pull of said deadline, means for balancing the beam against the load of the drill string supported by the cable and asserted by pull of the deadline on thebeam, a counterweight adjustable on the beam to th effect of applying weight to the drill string, control mechanism operable by the beam for effecting weight loading or unloading of th drill string in accordance withthe movements of said beam and a variable fulcrum for the beam shiftable relative to the beam for effecting initial leverage ratios as between the fulcrum and deadline connection centers of the beam.

3. Automatic control apparatus for maintaining desired weight, on the bit of a rotary drill having. cablesupportingthe drill string and terminating in a deadline, and comprising a beam fulcrumed for balancing movements and equipped with means for effecting connection of the deadline therewith and whereby said beam will be subject to the pull of said deadline, means for balancing the beam against the load of the drill string supported by the cable and asserted by pul1 of the deadline on the beam, a counterweight adjustable on the beam to the effect of applying weight to the drill string, control mechanism operable by the beam for effecting weight loading or unloading of the drill string in accordance with the movements of said beam and motor driven mechanism on the beam for shifting said balance weight.

4. Automatic control apparatus for maintaining desired Weight on the bit of a rotary drill having cable supporting the drill string and terminating in a deadline, and comprising a beam fulcrumed for balancing movements and equipped with means for eiiecting connection of the deadline therewith and whereby said beam will be subject to the pull of said deadline, means for balancing the beam against the load of the drill string supported by the cable and asserted by pull of the deadline on the beam, a counter weight adjustable on the beam to the effect of applying Weight to the drill string, control mechanism operable by the beam for efiecting weight loading or unloading of the drill string in acoordance with the movements of said beam and motor driven mechanism on the beam for shifting said balance weight and said control mechanism including connections for eifeoting operation of said balance motor.

5. Automatic control apparatus for maintaining desired weight on the bit of a rotary drill having cable supporting the drill string and terminating in a deadline, and comprising a beam fulcrumed for balancing movements and equipped with means for effecting connection of the deadline therewith and whereby said beam will be subject to the pull of said deadline, means for balancing the beam against the load of the drill string supported by the cable and asserted by pull of the deadline on the beam, a counterweight adjustable on the beam to the effect of applying weight to the drill string and control mechanism operable by the beam for effecting weight loading or unloading of the drill string in accordance with the movements of said beam and including valve mechanism having a controller shiftable by said beam.

6. Automatic control apparatus for maintaining desired weight on the bit of a rotary drill having cable supporting the drill string and terminating in a deadline, and comprising a beam fulcrumed for balancing movements and equipped with means for efiecting connection of the deadline therewith and whereby said beam will be subject to the pull of said deadline, means for balancing the beam against the load of the drill string supported by the cable and asserted by pull of the deadline on the beam, a counter-weight adjustable on the beam to the efiect of applying weight to or subtracting it from the drill string and control mechanism operable by the beam for effecting weight loading or unloading of the drill string in accordance with the movements of said beam, and a winch controllable for winding in or paying out said deadline, said beam having a sheave over which said deadline passes in its run to said winch.

7. Automatic weight control mechanism for a rotary drilling rig having draw works for spooling the hoisting cable supporting the drill string and bit and with the cable terminating in a deadline, means for controlling the draw works for applying Weight or taking weight off the bit, a beam fulcrumed for balancing movements and having means for effecting connection of the deadline thereto at one side of the beam fulcrum and means operated by said beam for effecting actuation of said draw works controlling means, and a separately controlled winch for spooling the end of said deadline, said beam having a sheave constituting the means for efiecting connection of the deadline and over which the deadline is looped on its way to said separately controlled winch.

JAMES W. DES CHAMPS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,294,089 Graham Feb. 11, 1919 1,779,581 Behnke Oct. 28, 1930 2,068,565 OKey Jan. 19, 1937 2,073,445 De Iongh Mar. 9, 1937 2,348,382 I-Ialby May 9, 1944

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