US 2998990 A
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Description (OCR text may contain errors)
p 1961 R. L. PLATTSMIER ETAL 2,998,990
SWAB MANDREL 2 Sheets-Sheet 1 Filed Aug. 4, 1958 Rodney L. Plahsmier Morgan L.Crow
INVENTORS ATTORNEYS p 1961 R. PLATTSMIER ET AL 2,998,990
SWAB MANDREL Filed Aug. 4, 1958 2 Sheets-Sheet 2 Rodney L. Plohsmier Morgan L. Crow INVENTORS WM BYZQZW 7mm ATTORNEYS United States Patent 6 This invention is concerned with a mandrel or support for swab cups is used in removing fluid from wells.
The invention is an improvement in that type of swab support disclosed in the co-pending application for patent of Norman W. Read, Serial No. 723,804, filed March 25, 1958, entitled, Swab Cup Support.
In such co-pending application, a swab cup support is disclosed comprised of a plurality of sections having oints therebetween which are'easily and quickly connected and disconnected without the employment of threads or other fixed connections, and which joints also permit relative rotatable and pivotal movement between the separate sections.
The construction and advantages of such a swab support are fully described in the said co-pending appiication, to which reference is here made.
However, in the use of a swab support such as that described in said co-pending application, it has been found that on some occasions the joints may become disconnected, allowing a section of the swab support to freely fall into the well pipe.
The reason for 'such accidents is that the lower section of such support sometimes becomes lodged in the well pipe at the surface as the swab is being inserted therein. In such event the weight of the elongated sinker bar, attached at the upper end of the swab support, may cause the sections of the swab support to buckle at the joints and move to substantially right angular position with relation to each other as the sinker bar swings to the side and is lowered, in which position the joints may become separated.
It has been found, however, that the joints between the separate sections of the swab support cannot bend and allow the sections to move to right angular position with relation to each other unless the sockets in the separate joints are turned to face in opposite directions.
This is so by reason of the fact that the sinker bar is suspended to a cable and remains in substantially upright position. Therefore, the head section to which the sinker bar is attached will also remain in upright position. The base section is held upright in the pipe in; which it is lodged, so that in order for the swab support sections to come apart the intermediate section must move to horizontal position. Such movement is permitted if the sockets and intersecting slots in the joints are turned substantially 180 apart, but such movement is impossible if the sockets and intersecting slots in the joints face substantially in the same direction, as long as the sinker bar, head section and base section remain in an upright position.
It is therefore aprimary object of this invention to provide means to maintain the sockets and intersecting slots in the joints between separate sections of such a swab support in substantial alignment and prevent them from rotating substantially 180 apart.
- It is another object of this invention to provide means for locking or keying all of the joints, except the lowermost joint, in such a swab support against relative rotation so as to maintain the sockets and intersecting slots in such joints in substantial alignment and prevent them from rotating substantially 180 apart.
A still. further object of the invention is to provide a joint between separate sections of a swab support of the type referred to which is quickly connectable and disconnectable without the employment of threads or other rigid type attachments, which permits limited pivotal movement between the separate sections, and limits rotatable movement between the separate sections.
A still further form of the invention is to provide a swab support of the type referred to in which the separate sections are prevented from moving to right angular position with relation to each other when the lowermost section is lodged in the open end of a pipe.
Other and further objects of the invention will become apparent upon reading the detailed specification hereinafter following and by referring to the drawings annexed hereto.
In the drawings suitable embodiments for carrying out the invention are disclosed in which:
FIGURE 1 is a side elevational view of a swab support assembly incorporating one form of the improvements disclosed and claimed herein.
FIGURE 11 is a side elevational view of the intermediate section of the swab support on which one form of the locking rib is provided.
FIGURE III is a side elevational view of the intermediate section of swab support taken at right angle to the view shown in FIGURE II.
FIGURE IV is a full sectional, elevational view of the intermediate section of the swab support as shown in FIGURE III.
FIGURE V is a side elevational view of the base sec-' tion of the swab support.
FIGURE VI is a fragmentary, partially sectionalized, view of a typical joint between swab sections, with the head on one section inserted in the socket of another section in right angular position, and showing the locking rib to limit rotation therebetween when the sections are in alignment.
FIGURE VII is a cross-sectional view taken on the line VIIVII of FIGURE VI.
FIGURE VIII is a fragmentary, partially sectionalized, elevational view showing the joint after the separate swab sections have been turned to a position of alignment.
FIGURE IX is a front elevational view of the joint taken from the left sideof the joint as shown in FIG- URE VIII.
FIGURE X is a cross-sectional, horizontal view taken on the line XX of FIGURE IX.
FIGURE XI is a side elevational view of an intermediate swab section showing a modified form of locking rib.
FIGURE XII is a side elevational view taken at right angle to the swab support shown in FIGURE XI.
Numeral references are employed to designate the various parts of the devices shown in the drawings, and' pulley on a mast thereabove and is lowered andmaisd" by a hoist mechanism on a truck. The sinker bar provides weight to facilitate the lowering by gravity of the' swab into the well pipe. All of such suspending, lowering and raising mechanisms are conventional in the swabbing art, and it is not necessary to disclose same herein for an understanding of the present invention. The swab support also includes an intermediate section 3 and a base section 4. There may be as many of the intermediate sections 3 as may be desired to support the number of cups required.
The intermediate section 3 includes an enlarged shoe assaaeo a 5, and the base section 4 has an enlarged guide shoe 6 formed on the lower end thereof. The guide shoe 6 includes spaced ribs 6a thereabout, providing grooves 6b, through which fluid may pass as the swab is lowered into a well pipe.
The intermediate section 3 and the base section 4 include stem portions 8 and 25, respectively, on which are slidably disposed suitable resilient swab cups 7. Each swab cup 7 has a central bore 9 therethrough which slide over the stems S and 25, and such stems 8 and 25 are elongated so that the swab cups can move longitudinally thereon. The particular construction of the swab cup is not important to this invention as several diiferent types may be used with the support.
Each of the stems 8 and 25 is formed with longitudinal flutes or grooves 10 and 27, respectively, on the outer sides th f, ich gr o e a sepa a ed b r 11 and 26.
vAs the swab assembly shown in FLGUREI is lowered through a column of fluid in a well pipe, the cups 7 are caused to move upwardly on the stems 8 and 25, permitting fluid to pass through the flutes 10 and thus bypass the swab cups. Such bypass of fluid permits the swab assembly to be more easily lowered into the column of fluid. When the swab assembly is pulled upwardly under a column of fluid, the cups are caused to move downwardly to a position of rest on the shoes 5 and 6, trapping the fluid above the cups, expanding them into sealing engagement with the well pipe, thereby permitting the fluid column above the swab to be withdrawn from the well.
The intermediate section 3 includes a head portion 12 on the upper end thereof, whichhead has a central cylindrical portion 13, a spherical outer end 14, and rounded spherical sides 15 at the inner end thereof. Thus the length of the head 12 is greater than its diameter. The head 12 is joined to the stem 8 by a neck 16 which has a portion 17 of reduced radius, and the other side of the neck 16 has a widened locking rib 18 thereon which is co-extensive with the outer surface of arib 11, of which it is a continuation, and has a radiusthe same as the cylindrical part 13 of the head 12.
It will be noted that the radius of the cylindrical surface 13 is less than the radius of the spherical surfaces 14 and 15 for the purposes hereinafter described.
The head section 1, and the shoe 5 on the intermediate section, each has a socket formed therein which are identical in construction and function, and the description of one such socket will sufiice for the description of both, and same will be described in connection with the head section or body 1. Such construction is shown in detail in FIGURES VI-X.
As shown, the socket'20 is generally spherical in shape. A circular passage or port 21, of less diameter than the socket 20, is provided through the Wall of the body 1, said passage intersecting the socket 20. A slot 22, of less width than the diameter of the passage 21 or of the socket 20, is provided in the wall of the body 1, said passage intersecting both the socket 20 and the passage 21 and opening at the lower end of the body.
It will be noted, as shown in 'FIGURES VI and VII that the cylindrical diameter 13 of the head12 is such thatit will pass through the passage 21 when the intermediate sectionis turned in right angular position with relation to the body 1 with the locking rib 18 in outwardly faci g position. Then when the intermediate section 3 is rotated to a position ofalignment with the head section 1 the neck portion 16 will pass through the slot 22. When the sections 1 and}; areso rotatedinto alignment the greater radius of the head 12, between the spherical ends 14 and 15 thereon cannot pass through the passage 21 and the head 12 is suspended in the socket 20 and cannot be disengaged until the body .1 and intermediate section 3 are again rotated to right angular position with relation. to each other. ,Howevenlirnited lateral movement a} is permitted between the body 1 and the intermediate section 3.
Relative rotation between the body 1 and the intermediate section 3 is prevented by reason of the fact that the locking rib 18 provides a greater radius on the neck 16 than the width of slot 22, as clearly shown in FIGURE X, so that the intermediate section 3 cannot rotate in the slot 22. Therefore, the turning of the body or head section 1 will also turn the intermediate section 3 thereby keeping the socket in the head section and the socket in the base of the intermediate section in substantial alignment, so that such sections and the base section cannot move to right angular position with relation to each other to accidentally come apart under the conditions hereinbefore indicated. A i
It will be understood that if' more than three sections of the swab are used, all of the sections, except the lowermost section, would haveiailocked joint therebetween as hereinbefore described. i
Preferably the lower section 4 should be allowed to swivel and rotate with relation to the intermediate section immediately above so that the lower section may rotate and move laterally ms limitedextent for the purpose of permitting it to bemore' easily worked through irregular places in the well pipe.
However, it will be understood that the lock joint hereinbefore described could be used in the joints between all sections used in the swab assembly and still the joints would have the advantage of being more easily and quickly connected and disconnected, without the employment of threads or other fixed joints. Furthermore limited lateral movement would be provided between the separate sections, providing more flexibility in the swab assembly. r
The base section 4 is arranged to swivel with relation to the intermediate section 3. It includes a stem 25 having longitudinal ribs 26 thereon'providing longitudinal flutes 27 for the purpose hereinbefore described. The head 28 has an intermediate cylindrical surface 29 and a spherical upper end 30 and spherical lower edges 31. The head is joined to the stem 25 by a reduced neck 32. The head 28 is engaged with the socket 20 in the same manner as was described with reference to head 12. However, since there is no locking rib, like that shown at 18, in conjunction with the neck portion 32, the neck portion is of such diameter that it will rotate in the slot 22, but the head 28 is suspended in the socket and cannot be retracted therefrom until the base section 4 is turned to right angular position with reference to the intermediate section, as shown in FIGURE VI.
A modified form of locking arrangement between the head and socket is shown in FIGURES XI and XII. This includes a narrower rib 33 which is co-extensive with one of the ribs 11 and conforms to the outer surface of the cylindrical portion 13 of the head. The rib 33 is in alignment with the passage 21 and slot 22 in the shoe 5 so that the sockets in the head 1 and shoe 5 are maintained less than apart, whereby they cannot accidently come apart under the conditions mentioned hereinbefore. Such a rib 33 would extend outwardly into the slot 22 and will permit limited rotational movement between the head 12 and socket 20, but provides a diameter on the neck 16 greater than the width of slot 22 to engage the wall of the slot 22 when rotated thereagainst to prevent further relative rotative movement. This will prevent the sockets 20 from becoming oppositely disposed and thus prevent the swab support sections from moving to right angular position, as hereinbefore explained, thus preventing them from coming apart.
All that is necessary is that the passages and slots 22 in the joined swab support sections be prevented from becoming oppositely disposed at substantially 180 apart. This purpose may be accomplished .by any kind of an outwardly extending rib, such as 18 or 33, or even a raised portion, or outwardly extending pin, on the neck B4! of the intermediate section to provide a lengthened radius on the neck to thereby prevent the intermediate section from rotating with reference to the socket.
It will be understood that other and further forms of the invention may be devised without departing from the spirit and scope of the appended claims.
1. In a device of the class described; a body having a socket therein intersected by a passage and a slot, the passage being less in diameter than the socket and the slot being less in width than the diameter of the passage, the said slot providing an opening from the socket and the passage through the lower end of the body; a swab cup support; a head member forming a part of the swab cup support, the said head member having a width less than the diameter of the passage so as to pass through the passage and a length greater than the diameter of the passage, whereby the head member may be passed through the passage into the socket in one position but will not pass through the passage and slot in another position; a neck portion joining the head to the swab cup support, said neck portion having one width less than the width of the slot so as to enter the slot, and another width greater than the width of the slot whereby the neck portion will not rotate in the slot.
2. The combination called for in claim 1 wherein the socket is semi-spherical in shape and the head has a cylindrical mid-portion and spherical end faces.
3. In a device of the class described; a body having a socket therein intersected by a passage and a slot; the passage having a cross-sectional area less than that of the socket, and the slot being less in width than the Width of the passage, the said slot providing an opening from the socket and the passage through the lower end of the body; a swab support; a head on the swab support, the said head being longer than it is wide and having a width less than the diameter of the passage so as to pass through the passage and a length greater than the diameter of the passage; a neck joining the head to the support; said neck having one width less than the width of the slot so as to enter the slot and another width greater than the width of the slot whereby the neck will not rotate in the slot.
4. In a device of the class described; a body having a. socket therein intersected by a passage and a slot; the passage having a cross-sectional area less than that of the socket, and the slot being less in width than the width of the passage; the said slot providing an opening from the socket and the passage through the lower end of the body; a swab support; a head on the swab support, the 5 the passage and a length greater than the diameter of the passage, the swab support having a portion thereon adjacent the head narrower than the slot so as to enter the slot; and means on such portion engageable with the wall of the slot to prevent rotation of the head in the socket.
5. The combination called for in claim 4 wherein the means for preventing rotation comprises a rib on one side of the support member adjacent the head.
6. The combination called for in claim 10 wherein the means for preventing rotation between the head section and support section comprises an enlarged radius on one side of the support section within the slot engageable with the wall of the slot.
7. The combination called for in claim 10 wherein the means for preventing rotation between the head section and support section comprises a rib on the support section engageable with the wall of the slot.
8. The combination called for in claim 7 wherein the rib is co-extensive with the surface of the head which is insertable through the passage.
9. The combination called for in claim 10 wherein the support section has a plurality of longitudinal ribs thereon, one of which is co-extensive with the outer surface of the head thereon and the other ribs are cut away adjacent the head to thereby provide a neck adjacent the head, one width of which will enter the slot and the other width of which is greater than the width of the slot to prevent rotation of the neck therein.
10. In a swab, a head section, a swab cup support member suspended to the head section, a socket in each of the head and support members; a passage into each socket of less diameter than the diameter of the socket; a head on the support member, said head having a width less than the diameter of the passage so as to be insertable through the passage in one position and a length greater than the diameter of the passage but less than the diameter of the socket; a slot in the wall of each head and support section, said slot being less in width than the diameter of the passage; said support member having a width adjacent the head thereon less than the width of the slot arranged to pass through the slot; and means to prevent rotation between the head section and support.
References Cited in the file of this patent UNITED STATES PATENTS 596,490 Edwards Jan. 4, 1898 709,762 Greaves Sept. 23, 1902 835,160 Lutz Nov. 6, 1906 2,333,671 Peters et a1. Nov. 9, 1943 2,486,483 Landen Nov. 1, 1949