US20030192688A1 - Tubing saver rotator and method for using same - Google Patents

Abstract

The present invention relates to a tubing rotator assembly for attachment to an existing casing head for purposes of suspending and rotating a tubing string in an oil well. In the preferred embodiment, the tubing assembly includes a rotation surface, such as a bearing, in which a tubing mandrel rests and allows one to rotate the tubing manually above the wellhead. It provides a low profile reducing the distance between the casing head and the pumping tee, which may eliminate the need for one to raise the pumping unit to fit on the rotator. In addition, the conventional seals above the rotation surface have less chance of leaking fluids located between the casing and tubing due to the seals potentially installed in the present invention. In addition, if the conventional seals do start to leak, then one can change the packing rubber without having to remove the tubing rotator assembly or tubing string (thus, not requiring a rig to change the sealing elements). The tubing assembly includes a mandrel bowl that rests inside the casing head. The mandrel bowl has an interior ledge in which the bearing may be placed on top of the ledge. A tubing mandrel is partially contained within the interior of the mandrel bowl with one end exiting the bottom of the bowl and attached to the tubing string in the well, and the opposite end of the tubing mandrel exiting the top of the bowl. The tubing mandrel has a ledge which is rotatably mounted to the mandrel bowl. Said ledge of the tubing mandrel is supported on the bearing, which bearing rests on the interior ledge of the mandrel bowl. The ledge of the tubing mandrel therefore engages and rotatably rides against the bearing. This arrangement allows the tubing to rotate by rotating the tubing mandrel resting on the bearing located inside the mandrel bowl.

Description

CROSS REFERENCES TO RELATED APPLICATIONS
• U.S. Provisional Application for Patent No. 60/371,393, filed Apr. 10, 2002, with title “Tubing Saver Rotator and Method For Using Same” which is hereby incorporated by reference. Applicant claims priority pursuant to 35 U.S.C. Par. 119(e)(i).[0001]
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
• Not Applicable[0002]
BACKGROUND OF THE INVENTION
• 1. Field of the Invention[0003]
• This invention relates to a tubing rotator assembly that sits inside a casing head for purposes of suspending and rotating the tubing string in an oil well.[0004]
• 2. Brief Description of Prior Art[0005]
• A typical wellhead is often comprised of a casing head which engages or is otherwise mounted to a casing string contained within a wellbore of a well at the surface. A mandrel bowl is mounted to the casing head and provides a support mechanism for the tubing string which is contained within the wellbore.[0006]
• The production of fluids from an oil and gas well often involves the use of a downhole pump that can pump fluids to the surface through the tubing string. This downhole pump is often mechanically actuated through the use of a rod string located within the tubing string. The rod string is usually reciprocated up and down at the surface or, rotated at the surface to impart motion on the pump. The reciprocation or rotation of the rod string causes the rods to wear against the tubing, which may cause the tubing string to wear thin and develop a hole in the tubing. This wear action also wipes off chemical inhibitors that may be placed into a well to minimize corrosion of the tubing and rods by the production fluids. Thus, the wear action can also lead to tubing holes due to corrosion since the inhibitors are wiped off. These wear related holes in the tubing causes inefficient lift or no lift of the fluids to the surface and typically requires a rig to service the well. Reducing the failure frequency of the tubing strings will not only reduce operating costs but also will allow additional oil to be developed by reducing the economic production rate limit of each well.[0007]
• Since 1927, several patents have been obtained on variations to tubing rotators that generally rotate the tubing manually or automatically to attempt to reduce the frequency of tubing holes developed due to the wearing action of the rods. Conventional casing heads are not typically able to be retrofitted to accommodate the necessary structure of a tubing rotator. Further, the tubing rotators of the prior art typically use gears and drive assembly to rotate the tubing. As a result, a housing is normally required to be attached above the casing head to provide room for the gearing and allow a rod to exit the tubing rotators of the prior art to allow manual rotation or automatic/continuous rotation of the tubing string.[0008]
• These prior art designs therefore often include several seals to seal off the rod attached to the gears, seal the fluids between the casing and tubing, and further seal fluids produced up the tubing from exiting the tubing string into the atmosphere, ground, or annulus between the tubing and casing. The rotators with continuous rotation commonly have more corrosion holes due to wear than a manual or intermittent rotator, and fail when a gear mechanism fails and may damage the rotator or wellhead assembly due to the torque imparted on the gears. In addition, the positioning of a housing on top of the casing head is more costly and may involve the need to raise the pumping unit due to large spacing requirements between the casing head and the pump tee.[0009]
• As will be seen from the subsequent description, the preferred embodiments of the present invention overcome these and other shortcomings of prior art.[0010]
• There is need for a compact tubing rotator that may be operated manually, reduces the height clearance between the casing head and the pump tee, is inexpensive, has minimal seals to potentially fail and leak fluids, provides for replacement of rubbers or seals that protect the atmosphere and environment from leaking fluids without removing the tubing rotator or tubing string from the well, provides additional seals to minimize or stop contamination of the grease packed bearing housing from wellbore or external fluids, utilizes commonly available equipment to reduce costs of repairs, and provides ease of installation and use.[0011]
• The present invention is an apparatus for attachment within an existing casing head or within a casing head modified to accept a bowl or ledge assembly. In the preferred embodiment, this apparatus has a bearing in which a tubing mandrel rests and allows one to rotate the tubing manually above the wellhead. It provides a low profile reducing the distance between the casing head and the pumping tee, which may eliminate the need for one to raise the pumping unit to fit on the rotator. In addition, the conventional seals located above the bowl assembly have less chance of leaking fluids located between the casing and tubing as a result of the seals installed in the present invention. In addition, if the conventional rubber element starts to leak, then one can change the sealing elements without having to remove the tubing rotator assembly or tubing string from the well.[0012]
SUMMARY OF THE INVENTION
• This invention relates to a tubing rotator assembly that sits in a casing head for purposes of suspending and rotating the tubing string in an oil well. The assembly includes a mandrel bowl or mandrel support that rests in the casing head. The mandrel bowl has an interior ledge with a surface on which a bearing may be placed. A tubing mandrel is partially contained within the interior of the mandrel bowl with one end exiting the bottom of the mandrel bowl and attached to the tubing string in the well, and the opposite end of the tubing mandrel exiting the top of the mandrel bowl. The tubing mandrel has a ledge which is rotatably mounted to the mandrel bowl. Said ledge of the tubing mandrel is supported on the bearing, which bearing rests on the interior ledge of the mandrel bowl. The ledge of the tubing mandrel therefore engages and rotatably rides against the bearing. This arrangement allows the tubing to rotate by rotating the mandrel residing on the bearing disposed on the interior ledge of the mandrel bowl. The top of the tubing mandrel may be connected to a swivel, or be an integral part of the swivel, or connected to a union in such a manner to allow one to rotate the tubing by turning the mandrel and or rotating part of the swivel. Normally, one would use a handle or pipe wrench to manually turn the mandrel or swivel or union that extends above the wellhead or, a device known in the art may be applied to automatically turn the mandrel or swivel or union..[0013]
• Seals are provided (but not necessary) to isolate the interior of the mandrel bowl from fluids from the well or outside the well, thereby preserving any lubrication of the bearings and minimizing corrosion or contamination inside the mandrel bowl area. Seals may also be placed on the outside of the mandrel bowl or bowl plate, or inside the casing head, in order to provide additional sealing of the fluids between the casing and tubing strings. A bowl plate is positioned on top of the mandrel bowl with seals preferred to allow sealing between the bowl plate and the mandrel bowl and also between the bowl plate and the tubing mandrel. This allows the tubing rotator assembly to be a self contained unit with connection ends above and below the mandrel bowl to allow connection to the tubing string below the mandrel bowl and connection to a swivel, union, or other material to allow fluids to exit the wellbore from the tubing.[0014]
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is a front view of a preferred embodiment of the present invention, a tubing saver rotator.[0015]
• FIGS.[0016]2-4 are front views of the tubing rotator saver of FIG. 1 without the standard equipment generally found on wellheads.
• FIG. 5 illustrates a front view of an alternate embodiment of the present invention.[0017]
• FIG. 6 illustrates a front view of a second alternate embodiment of the present invention.[0018]
DESCRIPTION OF THE PREFERRED EMBODIMENT
• FIGS.[0019]1-4 illustrate a preferred embodiment of a tubingsaver rotator assembly100 made in accordance with the present invention. Generally, the present invention is an apparatus for attachment in an existing casing head or a casing head modified to accept a bowl or ledge assembly. This apparatus having a surface, such as a bearing in which a tubing mandrel rests and allows one to rotate the tubing above the wellhead. It provides a low profile reducing the distance between the casing head and the pumping tee, which may eliminate the need for one to raise the pumping unit to fit on the rotator. In addition, the conventional seals above the bowl assembly have less chance of leaking fluids located between the casing and tubing due to the seals potentially installed in the present invention. In addition, if the conventional seals do start to leak, one can change the sealing elements without having to remove thetubing rotator assembly100 or tubing string (not shown) from the well. In the preferred embodiment, the present invention includes a pin end projecting upwardly from the mandrel or from the swivel joint. This allows a rig to pick up the mandrel and attach it to the pump tee above the wellhead and to the tubing string below the mandrel by simply screwing on two connections as will be further described. A conventional screwdriver or hex wrench will allow replacement of all the seals in the bowl and tubing mandrel assembly if replacement becomes necessary. If the fluids between the casing head and tubing string start to leak around the wellhead, sealing elements may be tightened to effect a good seal, or the seal elements may be replaced and tightened without removing the tubing rotator or tubing string with a rig. This provides ease and speed of repair by one person in lieu of a conventional rig job, which may help the environment and lower operating costs.
• Referring to FIG. 1, the tubing[0020]saver rotator assembly100 includes amandrel bowl1 having aledge support1A, saidmandrel bowl1 positioned on aninterior lip17A within acasing head17. Atubing mandrel2 having an extendingmandrel ledge10 is rotatably mounted to themandrel bowl1. In the preferred embodiment, saidmandrel ledge10 of thetubing mandrel2 is substantially perpendicular to the length of thetubing mandrel2 however, it is understood that themandrel ledge10 may be disposed at other angles in relationship to thetubing mandrel2 and achieve the objectives described herein.
• Said[0021]mandrel ledge10 may be supported on the surface of theledge support1A of themandrel bowl1 or, as shown in the drawings, may be supported on abearing3, whichbearing3 rests on theledge support1A of themandrel bowl1. Themandrel ledge10 and theledge support1A therefore captures thebearing3 therebetween. Themandrel ledge10 of thetubing mandrel2 therefore engages and rotatably rides against thebearing3. Abowl plate4 is attached to themandrel bowl1 with bowl plate screws5 selectively located around thebowl plate4. A lowerinterior bowl seal6, abowl plate seal7, and amandrel plate seal8 prevents fluid from contaminating saidbearing3.
• The lower end of the[0022]tubing mandrel2 is attached to the tubing string (not shown) with alower connection9, and the opposite end of thetubing mandrel2 is attached to aswivel12 with anupper connection11. Said lower and upper connection means9,11, is known in the art. As shown in FIG. 1, theswivel12 is attached to anupper end2A of thetubing mandrel2, which allows alower part12A of theswivel12 to rotate with thetubing mandrel2. Anupper part13 of theswivel12 may be attached to a stationary pump tee (not shown). Aswivel cap14 connects thelower part12A of theswivel12 to theupper part13 of theswivel12, and seals15,16, and21 are provided in theswivel12 to prevent leakage or entry of fluids from thetubing mandrel2 or environment. A union (not shown) could be used in lieu of theswivel12 as well as substitution of other types of mechanisms known in the art to allow rotation or, thetubing mandrel2 may be attached directly to the pump tee with the pump tee designed to allow some movement or rotation.
• A rubber or packing[0023]element18 is disposed on top of thebowl plate4. Atop plate19 is then disposed on top of the rubber or packingelement18, saidtop plate19 is compressed down to squeeze therubber element18 between thetop plate19 and thebowl plate4 by acasing head dognut20. Thedognut20 may be removed to grease thebearing3 area if desired or to replace thetop plate19,rubber element18,bowl plate4, bowl plate screws5,bowl plate seal7, ormandrel plate seal8. This arrangement allows most seals to be easily replaced by one person without removing thetubing mandrel2 andmandrel bowl1 which would normally require a rig in prior art designs. Thedognut20 may be tightened down from time to time if any wellbore fluids start to leak out of thecasing head17 or it may be tightened after replacing therubber element18. Theseals6,7, and8 reduce the chance that therubber element18 will leak and thereby provides extra sealing protection.
• FIG. 2 illustrates the[0024]rotator assembly100 shown in FIG. 1 without the standard equipment normally on certain wellheads. Thus a rig only needs to pick up the entirepre-assembled rotator assembly100 and stab the bottom pin into the tubing string, lower themandrel bowl1 into the well with the rig, and then attach the swivel and/or pump tee (depending on if the rig desired to install the swivel separately or as one piece). Thebowl1 may then be packed off in the wellhead with the plates and rubber element that are standard equipment for that wellhead.
• Various options may be chosen to enhance or reduce the cost of the[0025]rotator assembly100. For example, theseals6,7, and8 may be eliminated, however fluids may enter thebearing3 area during installation or operation of the oil and gas well. Seals or packing could also be used between themandrel bowl1 andcasing head17 to provide extra backup seals or eliminate the need for thebowl plate seal7. If care is taken during installation, themandrel plate seal8 may be eliminated if therubber element18 is providing a good seal. In addition, themandrel plate seal8 may be replaced with a seal between the outer diameter of themandrel ledge10 and themandrel bowl1, a seal between thetubing mandrel2 and the inner diameter of thebowl plate4, and/or a seal between thetop plate19 and thetubing mandrel2. In addition, seals may be used between thebowl plate4 and thecasing head17, or between thetop plate19 and thecasing head17, in order to provide additional backup seals, or to eliminate therubber element18.
• FIG. 5 illustrates an alternate embodiment of a[0026]tubing saver rotator200. Therotator assembly200 includes atubing mandrel32 having an extendingmandrel ledge38. Saidmandrel ledge38 may be rotatably supported on atop surface31A of abottom plate31 or, as shown in FIG. 6, may be supported on abearing33, which bearing33 rests on thetop surface31A of thebottom plate31. Themandrel ledge38 and thebottom plate31 therefore captures the bearing33 therebetween. Themandrel ledge38 of thetubing mandrel32 therefore engages and rotatably rides against thebearing33. As shown in FIG. 5, thebottom plate31 disposed between aninterior edge50A of acasing head50 and anexterior edge32A of thetubing mandrel32. Thebottom plate31 therefore supports thebearing33. Amandrel plate34 rests on top of themandrel ledge38 and is disposed between theinterior edge50A of thecasing head50 and theexterior edge32A of thetubing mandrel32. A lowerinterior bowl seal36,exterior plate seal35, and amandrel plate seal37 prevents fluid from contaminating saidbearing33.
• The lower end of the[0027]tubing mandrel32 is attached to the tubing string (not shown) with alower connection39, and the opposite end of thetubing mandrel32 is attached to aswivel43 with anupper connection41. The lower and upper connection means39,41 are known in the art. Theswivel43 is attached to anupper end32B of thetubing mandrel32, which allows alower part42 of theswivel43 to rotate with thetubing mandrel32. Anupper part43A of theswivel43 may be attached to a stationary pump tee (not shown). Aswivel cap44 connects thelower part42 of theswivel43 to theupper part43A of theswivel43, and seals45,46, and51 are provided in theswivel43 to prevent leakage or entry of fluids from thetubing mandrel32 or environment. A union (not shown) may be used in lieu of theswivel43 as well as substitution of other types of mechanisms to allow rotation or, thetubing mandrel32 may be attached directly to the pump tee with the pump tee designed to allow some movement or rotation.
• A rubber or packing[0028]element47 is disposed on top of themandrel plate34. Atop plate48 is then disposed on the rubber or packingelement47, saidtop plate48 is compressed down to squeeze therubber element47 between thetop plate48 and themandrel plate34 by acasing head dognut49. Thedognut49 may be removed to grease the bearing33 area if desired or to replace thetop plate48,rubber element47,mandrel plate34, ormandrel plate seal37.
• Other options exist to use existing casing heads or modify the casing head design as shown in FIG. 5 to accept the[0029]bottom plate31 that provides thetop surface31A of thebottom plate31 for thebearing33 to be rotatably supported on, withseals35 and36 positioned around thebottom plate31, if desired. Further, other options exist to connect themandrel plate34 to thebottom plate31 such as using bolts, supports, or other connection means known in the art.
• The[0030]mandrel plate34 may include additional seals (not shown) on the internal and/or external diameter of themandrel plate34, if desired. It should be further understood that in shallow wells, the bearing33 may not be necessary to turn thetubing mandrel32 if a good surface is provided between thebottom plate31 and themandrel ledge38.
• The purpose of the present invention is to have the mandrel bowl[0031]1 (FIG. 1) or bottom plate31 (FIG. 5) for the support of the tubing mandrel rotatable on the bearing surface attached to the string of tubing in the well. A bearing may or may not be used between the mandrel ledge and the bowl ledge support or bottom plate. The bearing would preferably be a thrust bearing and could be of the cylindrical roller bearing, needle bearing, tapered roller bearing, spherical bearing, and/or ball bearings. Thrust washers or a good surface between the mandrel ledge and the bottom plate could be used if the thrust weight is low enough to allow rotation of the tubing mandrel.
• Referring again to FIG. 1, in the preferred embodiment seals are positioned between the[0032]tubing mandrel2 and themandrel bowl1, between thebowl plate4 and themandrel bowl1, and between thebowl plate4 and themandrel ledge10. Additional or alternate seals to prevent installation contamination or contamination from outside fluids if therubber element18 leaks, or contamination from inside fluids into thebearing3 area or external of thecasing head17, may be placed between thetubing mandrel2 and an interior4A of thebowl plate4, between themandrel ledge10 and themandrel bowl1, between thetubing mandrel2 and thetop plate19, between themandrel bowl1 and an interior17B of thecasing head17, between the interior17B of thecasing head17 and thebowl plate4, and/or between the interior17B of thecasing head17 and thetop plate19. From the above description it should be understood the present invention may allow the use of no seals or the use of any combination of seals between any combination of thetubing mandrel2,bowl plate4,top plate19,rubber element18,dognut20,mandrel bowl1, support ledges, and the casing head interior17B. Likewise, referring to the embodiment of FIG. 5, it should be understood the present invention may allow the use of no seals or the use of any combination of seals between any combination of thetubing mandrel32,bowl plate34,top plate48,rubber element47,dognut49,bottom plate31, support ledges, and the casing head interior.
• Further purpose of this invention is to allow one to attach a swivel or union to the top of the tubing mandrel. Referring to FIG. 3, the[0033]swivel12 may be attached to theupper end2A of thetubing mandrel2 or, as shown in FIG. 4, to allow for an integral part of theswivel12 to be built as part of the tubing mandrel2 (to reduce costs and also to reduce the clearance between the wellhead and pump tee). The swivel or union or the tubing mandrel may have edges placed on them to allow easier gripping of the tubing mandrel by a pipe wrench or a handle or automatic rotation device. In addition, one may place attachments to the rotator or swivel assembly to allow gearing or other means to rotate the tubing mandrel.
• Referring now to FIG. 6, illustrating a second alternate embodiment of the present invention, a tubing[0034]saver rotator assembly300 includes amandrel bowl110 having aledge support110 A, saidmandrel bowl110 positioned on alip117 of aflanged connection120. Saidflange connection120 allows for connection to the wellhead with bolts (not shown) placed throughbolt holes120A and sealing provided by a conventional ring seal (not shown) seated in a ring grove120B. An alternate arrangement is to integrally combine themandrel bowl110 and theflange connection120.
• A[0035]tubing mandrel130 is stabbed into themandrel bowl110 and rests on the surface of theledge support110A of themandrel bowl110 or, as shown in FIG. 6, may be supported on abearing140, which bearing140 rests on theledge support110A of themandrel bowl110. Abowl plate145 is attached to themandrel bowl110 with bolt plate screws115 selectively located around thebowl plate145. Fluids are prevented from entering the bearing140 area through a lowerinterior bowl seal116, abowl plate seal118, and amandrel plate seal119. The lower end of thetubing mandrel130 is attached to a tubing string (not shown) with alower connection125, and the opposite end of thetubing mandrel130 is attached to aswivel143 with anupper connection126. Saidswivel143 attached to anupper end132 of thetubing mandrel130, and allows alower part133 of theswivel143 to rotate with thetubing mandrel130. Anupper part133A of theswivel143 may be attached to a stationary pump tee (not shown). A union may be used in lieu of theswivel143 as well as substitution of other types of mechanisms known in the art to allow rotation. Further, as known in the art, thetubing mandrel130 may be attached directly to the pump tee.
• A rubber or packing[0036]element147 is disposed on top of thebowl plate145. Atop plate148 is then disposed on top of the rubber or packingelement147, saidtop plate148 is compressed down to squeeze therubber element147 between thetop plate148 and thebowl plate145 by acasing head dognut149. Thecasing head dognut149 may be removed to grease the bearing140 area if desired or to replace thetop plate148,rubber element147,bowl plate145, bowl plate screws115,bowl plate seal118, ormandrel plate seal119. This arrangement allows most seals to be easily replaced by one person without removing thetubing mandrel130 andmandrel bowl110 which would normally require a rig in prior art designs. In the preferred embodiment, thread means149A attaches thedognut149 to theflange connection120 as shown in FIG. 6, however other similar attaching means known in the art including flange means may be used. Theseals116,118, and119 reduce the chance that therubber element147 will leak and therefore provides extra sealing protection for emissions or entry of outside fluids into the wellhead.
• Other enhancements or modifications to the flanged tubing[0037]saver rotator assembly300 includes the addition of seals between any combination of thedognut149, theflanged connection120, thetop plate148, thetubing mandrel130, themandrel bowl110, or thebowl plate145. In addition, theflanged connection120 andmandrel bowl110 may be manufactured as one piece. In addition, the user may rely on theseals116,118, and119 disposed around themandrel bowl110, in place of thedognut149,top plate148, andrubber element147. One further example of modification to the tubingsaver rotator assembly300 as described above, is to have theflange connection120 and themandrel bowl110 manufactured as one piece, and usingseals116,118, and119 to prevent emissions or fluid entry into the wellhead, withseals118 and119 being replaceable without requiring use of a rig.
• Although the description above contains many specificities, these should not be construed as limiting the scope of the invention but as merely providing illustrations of a presently preferred embodiment of this invention.[0038]
• Thus the scope of the invention should be determined by the appended claims in the formal application and their legal equivalents, rather than by the examples given.[0039]

Claims (53)

We claim:

1. A rotator assembly in a casing head, wellhead or tubing head (hereinafter said casing head, wellhead or tubing head referred to as “casing head”) for rotatably suspending a tubing string in an oil well, said rotator assembly comprising:

a mandrel bowl in communication with the casing head, said mandrel bowl having a ledge support, said ledge support having a rotation surface,

a tubing mandrel rotatably mounted to the mandrel bowl, said tubing mandrel having an upper end, a lower end, and a mandrel ledge, wherein the rotation surface is disposed between said ledge support and the mandrel ledge of the tubing mandrel, wherein the mandrel ledge engages and rotatably rides the rotation surface,

a bowl plate positioned between the casing head and the tubing mandrel, and

a rotation means,

wherein the tubing mandrel is rotatably supported on the rotation surface,

wherein the lower end of the tubing mandrel is attached to the tubing string.

2. The rotator assembly as recited inclaim 1, further including at least one first seals disposed between the mandrel bowl and the tubing mandrel.

3. The rotator assembly as recited inclaim 1, further including at least one second seals disposed between the mandrel bowl and the bowl plate.

4. The rotator assembly as recited inclaim 1, further including at least one third seals disposed between the tubing mandrel and the bowl plate.

5. The rotator assembly as recited inclaim 1, further including at least one fourth seals disposed between the bowl plate and the casing head.

6. The rotator assembly as recited inclaim 1, further including at least one fifth seals disposed between the mandrel bowl and the casing head.

7. The rotator assembly as recited inclaim 1, wherein the mandrel ledge of the tubing mandrel is substantially perpendicular to the length of the tubing mandrel.

8. The rotator assembly as recited inclaim 1, wherein the rotation surface is a bearing.

9. The rotator assembly as recited inclaim 8, wherein the bearing is a thrust bearing.

10. The rotator assembly as recited inclaim 8, wherein the bearing is a roller bearing.

11. The rotator assembly as recited inclaim 8, wherein the bearing is a ball bearing.

12. The rotator assembly as recited inclaim 8, wherein the bearing is a thrust washer.

13. The rotator assembly as recited inclaim 1, wherein the bowl plate rests on the mandrel ledge.

14. The rotator assembly as recited inclaim 1, wherein the bowl plate rests on the mandrel bowl.

15. The rotator assembly as recited inclaim 1, wherein the upper end of the tubing mandrel is attached to the rotation means.

16. A rotator assembly in a casing head, wellhead or tubing head (hereinafter said casing head, wellhead or tubing head referred to as “casing head”) for rotatably suspending a tubing string in an oil well, said rotator assembly comprising:

a tubing mandrel having an upper end, a lower end, and a mandrel ledge,

a bottom plate having a rotation surface positioned between the bottom plate and the mandrel ledge, wherein the mandrel ledge engages and rotatably rides the rotation surface,

said bottom plate disposed between an interior edge of the casing head and an exterior edge of the tubing mandrel,

a mandrel plate positioned between the casing head and the tubing mandrel, said mandrel plate resting on the mandrel ledge, and

a rotation means,

wherein the tubing mandrel is rotatably supported on the rotation surface,

wherein the lower end of the tubing mandrel is attached to the tubing string.

17. The rotator assembly as recited inclaim 16, wherein the mandrel ledge of the tubing mandrel is substantially perpendicular to the length of the tubing mandrel.

18. The rotator assembly as recited inclaim 16, further including at least one first seals disposed between the bottom plate and the tubing mandrel.

19. The rotator assembly as recited inclaim 16, further including at least one second seals disposed between the bottom plate and the casing head.

20. The rotator assembly as recited inclaim 16, further including at least one third seals disposed between the mandrel plate and the tubing mandrel.

21. The rotator assembly as recited inclaim 16, wherein the rotation surface is a bearing.

22. The rotator assembly as recited inclaim 21, wherein the bearing is a thrust bearing.

23. The rotator assembly as recited inclaim 21, wherein the bearing is a roller bearing.

24. The rotator assembly as recited inclaim 21, wherein the bearing is a ball bearing.

25. The rotator assembly as recited inclaim 21 wherein the bearing is a thrust washer.

26. The rotator assembly as recited inclaim 16, wherein the upper end of the tubing mandrel is attached to the rotation means.

27. A rotator assembly inside a casing head, wellhead or tubing head (hereinafter said casing head, wellhead or tubing head referred to as “casing head”) for rotatably suspending a tubing string in an oil well, said rotator assembly comprising:

a mandrel bowl in communication with the casing head, said mandrel bowl having a ledge support, said ledge support having a rotation surface,

a tubing mandrel rotatably mounted to the mandrel bowl, said tubing mandrel having an upper end, a lower end, and a mandrel ledge, wherein the rotation surface is disposed between said ledge support and the mandrel ledge of the tubing mandrel, wherein the mandrel ledge engages and rotatably rides the rotation surface, and

a rotation means,

wherein the lower end of the tubing mandrel is attached to the tubing string.

28. The rotator assembly as recited inclaim 27, wherein the mandrel ledge of the tubing mandrel is substantially perpendicular to the length of the tubing mandrel.

29. The rotator assembly as recited inclaim 27, further including at least one first seals disposed between the mandrel bowl and the tubing mandrel.

30. The rotator assembly as recited inclaim 27, further including at least one second seals disposed between the mandrel bowl and the casing head.

31. The rotator assembly as recited inclaim 27, wherein the rotation surface is a bearing.

32. The rotator assembly as recited inclaim 31, wherein the bearing is a thrust bearing.

33. The rotator assembly as recited inclaim 31, wherein the bearing is a roller bearing.

34. The rotator assembly as recited inclaim 31, wherein the bearing is a ball bearing.

35. The rotator assembly as recited inclaim 31, wherein the bearing is a thrust washer.

36. The rotator assembly as recited inclaim 27, wherein the upper end of the tubing mandrel is attached to the rotation means.

37. A rotator assembly for rotatably suspending a tubing string in an oil well, said rotator assembly comprising:

a mandrel bowl in communication with a flange connection, said mandrel bowl having a ledge support, said ledge support having a rotation surface,

a tubing mandrel rotatably mounted to the mandrel bowl, said tubing mandrel having an upper end, a lower end, and a mandrel ledge, wherein the rotation surface is disposed between said ledge support and the mandrel ledge of the tubing mandrel, wherein the mandrel ledge engages and rotatably rides the rotation surface,

a bowl plate positioned between the flange connection and the tubing mandrel,

a rotation means,

wherein the tubing mandrel is rotatably supported on the rotation surface,

wherein the lower end of the tubing mandrel is attached to the tubing string.

38. The rotation assembly as recited inclaim 37, further comprising a packing element positioned on top of the bowl plate, a top plate positioned on top of the packing element, wherein the top plate is compressed in a downward direction by a casing head dognut thereby squeezing the rubber element between the top plate and the bowl plate, said dognut attached to the flange connection.

39. The rotator assembly as recited inclaim 37, wherein the mandrel ledge of the tubing mandrel is substantially perpendicular to the length of the tubing mandrel.

40. The rotator assembly as recited inclaim 37, further including at least one first seals disposed between the mandrel bowl and the tubing mandrel.

41. The rotator assembly as recited inclaim 37, further including at least one second seals disposed between the mandrel bowl and the bowl plate.

42. The rotator assembly as recited inclaim 37, further including at least one third seals disposed between the tubing mandrel and the bowl plate.

43. The rotator assembly as recited inclaim 37, further including at least one fourth seals disposed between the bowl plate and the flange connection.

44. The rotator assembly as recited inclaim 37, further including at least one fifth seals disposed between the mandrel bowl and the flange connection.

45. The rotator assembly as recited inclaim 37, wherein the rotation surface is a bearing.

46. The rotator assembly as recited inclaim 45, wherein the bearing is a thrust bearing.

47. The rotator assembly as recited inclaim 45, wherein the bearing is a roller bearing.

48. The rotator assembly as recited inclaim 45, wherein the bearing is a ball bearing.

49. The rotator assembly as recited inclaim 45, wherein the bearing is a thrust washer.

50. The rotator assembly as recited inclaim 37, wherein the bowl plate rests on the mandrel ledge.

51. The rotator assembly as recited inclaim 37, wherein the bowl plate rests on the mandrel bowl.

52. The rotator assembly as recited inclaim 37, wherein the upper end of the tubing mandrel is attached to the rotation means.

53. The rotation assembly as recited inclaim 37, wherein the flange connection is manufactured as an integral part of the mandrel bowl.

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