ROD ROTATOR ASSEMBLY FOR WELL PUMPING ROD STRINGS

Abstract

A mechanical rod rotator assembly comprising a mechanical rod rotator and an actuating mechanism for a mechanical pumping rod rotator, wherein the mechanism comprises a connecting arm and a guide member that slidably embraces the pumping rod, in order to allow a pivoting lever that is in connection with said connecting arm, to interact with the internal mechanism of the rod rotator to gradually rotate the pumping rod and thus avoid impartial wear caused by the constant up and down reciprocating movement of the same within the well, being in turn that the mechanism of the invention does not require special tools for its assembly and installation.

Claims

1. A rod rotator assembly for well pumping rod strings of the type comprising a mechanical rod rotator and an actuating mechanism for the rod rotator, wherein the actuating mechanism has a lower part mounted around a first sucker or polished rod and an upper part connected to said rod rotator which is provided with a pivoting lever that rises and falls capable of rotating an internal mechanism of the rotator during up and down movement of the pivoting lever to rotate an upper rotator cover, which upper rotator cover in turn rotates an upper coupling or clamp of said first sucker or polished rod gradually, to rotate the string of rods, wherein the actuating mechanism comprises, at least one tube having a top part connected to said pivoting lever, and a bottom part, height-adjusting means guided and telescopically extending along an interior of the at least one tube to be selectively fixed between different height adjustment positions, to reciprocally actuate said at least one tube, a fixing element passing through the at least one tube and said height adjustment means to fix said height-adjusting means to the at least one tube in a desired position, at least one fork-shaped guide element having a fork part removably extending around the rod string and a fork base connected to a bottom part of the height-adjusting means and, damping elements located at said fork part around the rod string, and wherein, said rod rotator has at least one stop means comprising an auxiliary arm which has a first end mounted on a pivot point of the pivoting lever of said rod rotator and a free end that comes into operative contact with a stop arranged on a side of said rod rotator.

2. A rod rotator assembly according to claim 1, wherein said at least one tube comprises at least an upper extension tube and at least a lower extension tube, coupled to each other by means of coupling means, said upper extension tube being connected at a top thereof to said pivoting lever, while said lower extension tube is provided with said height adjusting means, and said upper and lower extension tubes each has respective upper and lower through holes.

3. A rod rotator assembly according to claim 2, wherein said coupling means for connecting the upper and lower extension tubes, comprises end portions having slightly smaller diameter than an internal diameter of said upper and lower extension tubes, and an intermediate portion having a diameter approximately equal to an external diameter of said upper and lower extension tubes, and said end portions of the coupling means having smaller diameter have respective through holes, to coincide with the respective upper and lower through holes of said upper and lower extension tubes, the through holes of the end portions of the coupling means and the through holes of the upper and lower extension tubes receiving pins and cotters.

4. A rod rotator assembly according to claim 2, wherein said upper extension tube is connected to said pivoting lever of the rod rotator through a lever coupler that has a lower portion fitted inside said upper extension tube, with a through hole of the upper extension tube for coinciding with the upper through hole of said upper extension tube and being fixed by a pin-cotter assembly; the lever coupler having a fork-shaped upper portion having a through hole for connecting to a through hole provided at one end of said pivoting lever by a pin and cotter.

5. A rod rotator assembly according to claim 2, wherein said height adjusting means comprises an adjustment bar provided with a plurality of adjustment holes which are selectively connectable to the lower through holes of the lower extension tube by pin—cotter assembly.

6. A rod rotator assembly according to claim 1, wherein said height adjusting means has a lower end provided with a least a through hole connectable to a through hole of the fork base, said lower end of the height adjusting means being fixed to said fork base by a pin-cotter assembly.

7. A rod rotator assembly according to claim 1, wherein the fork shaped guide element has a “U” shape with free ends and pivoting closing means are provided, with the pivoting closing means having an end pivotally connected to one of the free ends of the “U” and another end removably connectable to the opposite free end of the “U”, and the another end of the pivoting closing and the opposite end of the free ends of the “U” have respective through holes by pin-cotter assembly.

8. A rod rotator assembly according to claim 7, wherein said dumping means comprises a plurality of dumping wheels along said “U” shape of the fork part and said closing pivoting means.

9. A rod rotator assembly according to claim 1, wherein said auxiliary arm is arranged at an angle between 0° and 45° in respect to the pivoting lever.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] For greater clarity and understanding of the object of the present invention, it has been illustrated in several figures, in which the invention has been represented in one of the preferred embodiments, all by way of example, wherein:

[0026] FIG. 1 shows a perspective view of the rotator actuating mechanism of the rod rotator assembly according to the present invention;

[0027] FIG. 2 shows an exploded perspective view of the actuating mechanism according to the present invention;

[0028] FIG. 3 shows an enlarged sectional view of a lower portion of a tube of the actuating mechanism of the rotator assembly according to the invention;

[0029] FIG. 4 shows an enlarged perspective view of an end portion of the actuating mechanism of the invention, which is mounted around the polished rod;

[0030] FIG. 5 shows a perspective diagram of a rod rotator of the rod rotator assembly, wherein the rotator has a stop according to the present invention;

[0031] FIG. 6 shows a perspective view of the pumping rod rotator assembly of the invention;

[0032] FIGS. 7 to 9 show different views of the possible stages of the installation of the pumping rod rotator assembly of the invention; and

[0033] FIGS. 10 and 11 show views of the movement performed by the rod rotator assembly of the invention when the pumping rods ascend or descend in operation.

DETAILED DESCRIPTION OF THE INVENTION

[0034] Referring now to the figures, it can be seen that the invention relates to a new sucker rod rotator assembly comprising a rod rotator for the oil industry and an actuating mechanism for the rod rotator, either for extraction of oil, gas or water, which allows the rotation of the pumping rods in a gradual and practical way, avoiding impartial (localized) wear in their external structure, in their connection couplings and in the inner diameter of the “tubing” or piping. Likewise, by means of the pumping rod rotator assembly of the invention, the use of cables or external equipment that occupy considerable physical space and that, in cases of failures or weather changes that may generate involuntary accidents, may be detrimental to installations and site personnel, is avoided, also avoiding the use of special tools for its installation and extending the useful life of the parts that comprise it.

[0035] Thus, the pumping rod rotator assembly of the invention comprises an actuating mechanism for a mechanical pumping rod rotator that is indicated by general reference 1 and comprises at least one tube 2 that may comprise one or more extension tubes, at least an upper one 3 and at least a lower one 4 coupled to each other by means of a coupling means 5 or respective fixing elements. Wherein, said upper extension tube 3 is connected at a top part thereof to a pivoting arm or lever 6 of a rod rotator 7 which also forms part of the pumping rod rotator assembly of the invention. The lower extension tube 4 is provided with a height adjustment means 8 that moves guided and longitudinally along the interior of tube 8 and which is selectively fixed between height adjustment positions by means of a fixing element that passes through said lower extension tube 4 and said height adjusting means 8.

[0036] Although the use of an upper and a lower tube is mentioned, this is not limiting for the invention, since a plurality of tubes of different sizes can be used depending on the requirements of each installation, as well as a single tube connected to the pivoting arm of the rotator and to the height adjustment means. In the case of using more than two extension tubes, a corresponding number of coupling means 5 shall be used for the respective connection between the parts. For its part, if a single tube is used, the coupling means 5 is annulled, having the single extension tube both in its upper part and in its bottom or lower part, the corresponding construction features to carry out the connection with both the pivoting arm 5 and the height adjusting means 8, and said features will be described below.

[0037] Each of said upper 3 and lower 4 extension tubes have upper 9-11 and lower 10-12 through holes, respectively. Likewise, said coupling means 5 of the upper and lower 4 tubes, comprises end portions 13-14 slightly smaller in diameter than the inner diameter of said tubes 3-4 so as to be able to fit into them, and an intermediate portion 15 of approximately equal diameter to the external diameter of said tubes 3-4, being that said end portions 13-14 of smaller diameter have respective through holes 16-17, being at least one, for example 16 but not limited thereto, in coincidence with the hole lower through hole 11 of the upper tube 3, while the other, for example 17 but not limited thereto, being in coincidence with the upper hole 10 of the lower tube 4, passing through it said fixing elements that comprise pins 18 and cotters 19.

[0038] It is emphasized that all the cotters used in the present invention can be of the R type, this not being a limitation for the invention since other types of fixing elements can be considered and used without any inconvenience, as long as they do not require the use of special tools for their placement that may lead to the usual problems in conventional mechanisms used in the field of art.

[0039] For its part, said upper extension tube 3 is connected to said pivoting arm 6 of the rod rotator 7 through an arm terminal 20 that has a lower portion 21 that can be fitted inside said upper tube 3, being a through hole 22 thereof in coincidence with the upper hole 9 of said upper tube 3 and fixed through a pin 23—cotter 24 assembly; and an upper portion 25 in the form of a fork having a through hole 26 that is in linear coincidence with a hole 27 provided at one end of said pivoting arm 6 of the rotator 7, being fixed thereto through a pin 28 and cotter 29.

[0040] Likewise, said height adjusting means 8 comprises an adjustment bar or arm 30 provided with a plurality of adjustment holes 31 which are selectively coincident with the lower hole 12 of said lower extension tube 4, being that said fixing element of both parts, comprises a pin 32—cotter 33 assembly. In this way, the height adjustment or telescopic actuation of the tube 2 is allowed, with said bar or arm 30 moving inside the lower extension tube 4, avoiding projections that could cause accidents or contact with other wellhead elements. In turn, said height adjusting means 8 has a lower end 34 provided with a last through hole 31 which coincides with a through hole 35 of a fork-shaped guide element 39, more particularly of a fork base 36, said lower end of the height adjusting means 8 being fixed to said base 36 through a pin 37—cotter 38 assembly.

[0041] For its part, it is highlighted that said guiding element 39 rests on a stuffing box 57 and transmits the movement to the pivoting arm of the rotator. It also works as an actuating guide through the polished rod. It is important to clarify that its function is to guide and it is not in permanent contact with the polished rod since it has protection means that will be described below. Said guide element 39 is connected to said bottom or lower part or end 34 of said at least one tube 2 through said base 36 of the fork and which is removably arranged around a first pumping rod or polished rod 40, being slidably coupled along it. Wherein, said guide element or fork 39 comprises a longitudinal proximal part 41 that is defined by said fork base 36, while each of the free ends 42 of the distal “U” part 43 has a through hole 44, wherein in turn a pivoting closing means 45 is provided with end holes 46 coinciding with the through holes 44 of the free ends of the fork 43 and fixed by means of respective pin 47—cotter 48 assemblies.

[0042] Said longitudinal proximal part 41 of the fork can be provided with an identifying means such as a reflective tape to identify the corresponding part at night or when there is poor visibility. While said pivoting closure means 45 pivots at one end, so that assembly on the polished rod is very simple, the closure means 45 is opened, being placed around the rod and closed by means of the pin and cotter without using special tools.

[0043] It is emphasized that, as can be seen, the present invention uses fixing elements such as pins and cotters R that do not require special tools, providing functionality and simplicity when assembling and/or replacing parts, thus optimizing installation times and related costs. Likewise, in order to reduce wear due to friction or rubbing and extend the useful life of the guiding means 39 and of the rod 40, said “U” part 43 of the fork and said closing means 45, have a plurality of damping elements 49 comprising respective wheels made of plastic material that can be, but are not limited to the invention, made of plastic material.

[0044] On the other hand, to prevent the pivoting arm 6 of the rod rotator 7 from positioning itself vertically causing the mechanism to jam and break, it is provided with at least one stop means 50 comprising an auxiliary arm 51 which has a first end 52 mounted on a pivot point 53 of the pivoting arm 6 of said rotator 7 and a free end 54 that comes into operative contact with a stop 55 arranged on one side of said rotator 7. Wherein, said auxiliary arm 51 is inclined with respect to the longitudinal development of the pivoting arm 6 of the rod rotator 7, forming an angle between 45° and 0° which prevents the pivoting arm 6 from being positioned vertically when a beam pumping unit 56 is at its top dead center (TDC). That is, the rotator housing has a fixed horizontal stop 55. The pivoting arm 6 of the rotator has the free end 54 that abuts against the fixed stop 55 and does not allow the arm 6 of the rotator to be positioned vertically, in this way when activating the mechanism the force exerted is perpendicular to the lever arm exerted by the pivoting arm 6 and not collinear to its center of rotation, preventing the pivoting arm 6 from getting stuck.

[0045] It is emphasized that the internal mechanism of the rod rotator 7 is widely known in the field of art and that for such reasons, we will not go into descriptive details about it, being the novel stop means 50 of the invention complementary and indispensable for the movement of the pivoting arm 6 and being able to be added to any known rod rotator, in order to avoid jamming and breakage of the parts that comprise it. The purpose of the new stop is to prevent the pivoting arm from being aligned with the work force in some random movement, which would generate breakage and render the equipment unusable. The arm shall always keep an angle with respect to the vertical to be able to pivot faced to the change of direction of movement of the rods, that is, the change from ascent to descent and vice versa.

[0046] In this way, the mechanical pumping rod rotator assembly of the present invention is constituted and built, which avoids the use of special tools, extends the useful life of the parts and reduces related costs thus improving the assembly and installation process in a much more practical, fast and easy way.

[0047] According to FIGS. 7 to 9, and with respect to the installation of the mechanism of the invention, it is possible to proceed, this not being limiting for the invention, as follows: [0048] 1. Placing the Rod Rotator on Hanger—FIG. 7: [0049] a) Stop and unload the pumping unit 56 [0050] a1) According to company safety procedures and regulations. [0051] b) Remove the clamp from the polished rod 58 [0052] b1) Remove spacers only for some markets like Argentina. [0053] c) Install rod rotator 7 (without actuation mechanism) [0054] c1) Check that the pivoting arm or lever 6 of the rotator is at a safe distance from the bridle. [0055] c2) Check that there are no interferences between the pivoting arm or lever and other nearby devices. [0056] d) Re-place the polished rod clamp 58. [0057] d1) Remove a ⅝″ spacer to maintain the pump height. (specific or only for Argentina) [0058] d2) Leveling disc, Leuter device, load cell, rod rotator, spacers, coupling. (only or specific for Argentina) [0059] 2. Measuring Distance for Actuator—FIG. 8: [0060] a) Load the pumping unit 57 and stop it at BDC. [0061] a1) Stop the pumping unit at the Bottom Dead Center (Head Down). [0062] b) Measure distance to assemble ACTUATOR [0063] b1) Measure the distance between the contact surface of the stuffing box 57 and the pivoting arm or rotator lever 6 of the rotator 7 in the horizontal position (activation position). [0064] 3. Assembling/Installing Actuator—FIG. 9: [0065] a) Assemble actuator [0066] a1) Add the extension tubes that will form tube 2 and that are necessary to approximate the measured distance. [0067] a2) Join the tubes by means of said coupling means, pins and cotters. [0068] b) Install actuator [0069] b1) Place the Terminal coupling or arm coupling or lever coupler 20 of the actuating mechanism at the end of said pivoting lever 6 of the rod rotator 7 by means of a pin and cotter. [0070] b2) Adjust the height of the adjustment bar 30 to the measured distance. [0071] b3) Place the fork around polished rod and close by placing pin and cotter.

[0072] Once the assembly of the invention has been installed, the operation is verified, according to FIGS. 10 and 11, wherein at the Bottom Dead Center (FIG. 11), the pivoting arm 6 is positioned horizontally and activates the mechanism of rotation of the rotator 7, verifying that the rotator cover 59 rotates using as a reference a visual position indicator conveniently arranged on the cover