US 3216500 A
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Description (OCR text may contain errors)
,Nov. 9, 1965 T. w. DIEHL 3,216,500
PLUG INJECTOR APPARATUS Filed Sept. 18, 1962 To cam e I 2 INVENTOR.
Thom 06 14 Dle/l/ gjma w HGENT United States Patent Office Patented Nov. 9, 1965 3,216,500 PLUG INJECTOR APPARATUS Thomas W. Diehl, Tulsa, Okla, assignor to The Dow Chemical Company, Midland, Mich., a corporation of Delaware Filed Sept. 18, 1962, Ser. No. 224,334 4 Claims. 16670) This invention relates to plug injector apparatus and particularly to apparatus used for injecting so-called cementing type plugs into the casing of earth wells during a well treating operation.
In conventional cementing plug injector apparatus the plug or plugs is usually held in .position in the injector apparatus by means of a pin which extends across the apparatus either through or below the plug. Extraction of the pins is often difiicult to accomplish in a timely manner because the pressures encountered during the cementing or other treating operation cause the pin to bind as it is being retracted.
Accordingly, a principal object of this invention is to provide an improved plug injector apparatus for use in treating earth wells.
Another object of this invention is to provide an improved, easy to actuate plug injector apparatus for use in treating earth wells.
In accordance with this invention there is provided plug injector apparatus comprising a hollow cylindrical body section adapted to receive a plug of the so-called cementing plug type. The plug is axially aligned with the longitudinal axis of the body section and is held in position prior to its release by an arcuate (generally semicircularly shaped) element which extends across the diameter of the body section with its convex part facing upwardly and supporting the lower .part of the plug.
Means are provided for rotating the arcuate element from a position where the elements convex part faces upwardly generally along the longitudinal axis of the body section to where the arcuate element lies perpendicular to the longitudinal axis of the body section along the wall of the body section. The plug is then forced, by pressure exerted from above, down the body section, past the arcuate element and into the well casing (not shown).
The invention, as well as additional objects and advantages thereof, will best be understood when the following detailed description is read in connection with the accompanying drawing, in which FIG. 1 is a side elevational view, in section, of injector apparatus made in accordance with this invent-ion, and
FIG. 2 is an exploded isometric view showing the plug releasing mechanism of the apparatus shown in FIG. 1.
Referring to the drawing, there is shown plug injector apparatus, indicated generally by the numeral 10, which comprises an elongated generally tubular body section 12 which has an upper end cap 14 coupled thereto by means of threads 16. Threads 18 at the lower end of the body section provide the means by which a coupling element, such as the collar 20, couple the injector apparatus to other well head apparatus 22, a line 40, a valve 42 and thence to the casing (not shown) of the well under treatment.
The body section 12 has a first pumpable materials inlet 24 near its upper end and a second pumpable materials inlet 26 near its lower end. Inlets 24 and 26 are coupled by means of lines 28, 30 and valves 32, 34, respectively, to a line 36 which is coupled to the cement pump as indicated by the numeral 38.
Between the inlets 24, 26, and usually near the lower inlet 26, are disposed diametrically opposite bores 44, 48. The bore 44 extends only part way through the body section from the inner wall 78 thereof. The bore 48 extends through the wall of the body section and through the boss 46. The bore 48 has a generally circular groove 67 along its wall. A bore 50 extends from the outer surface of the boss 46 to the bore 48.
An arcuate, generally semi-circular shaped plug retaining element 56 is disposed within the hollow part of the body section, the element 56 being coupled to the bores 44, 48 which are axially aligned with one another. The retaining element 56 comprises a curved strip of spring steel plus the outwardly extending and axially aligned studs 58, 60. The stud 58 extends into the bore 44, the depth of the bore-being slightly greater than the length of the stud 58.
The stud 60 extends into the bore 48 and is coupled to the forked end 66 of the plug retainer actuating rod 62. The actuating rod 62 is adapted to fit slidably within the bore 48, an O ring seal 54 fitting in the groove 67 in the bore 48 and the aligned groove 68 (see FIG. 2) in the rod 62. The rod 62 also has a groove 70 which, when the rod is operatively aligned in the bore 48, is aligned with the bore 50. Set screw 52, screwed into the threaded bore 50, extends through the groove 68, keeping the rod 62 in the desired position within the bore 48 whereby the forked end 66 properly engages the stud 60. A barlike handle 65 is secured to the outer end of the rod 62. The handle contains a bore 72 through which indexing pin 74 may be inserted to engage the boss 46 and hold the retainer element 56 in the plug holding position. The indexing pin 74 is secured to the handle 65 (see FIG. 1), for example, by means of the small chain 76.
In operation, with the valve 32 closed, the valves 34 and 42 open, and a plug 64 in the body 12 of the apparatus 10 above the retainer element 56 (which is in the hold posit-ion), cement or other pumpable material is pumped into the well casing.
When it is desired to drive the plug 64 down the well casing, the retainer element 56 is turned degrees whereby it lies against the ledge 63 and thinned wall part 69, more or less out of the path 'of the plug 64 as it passes down the apparatus and into the well casing. The plug 64 is forced down the apparatus by opening valve 32 and then at least partially closing the valve 34 to provide a greater force above the plug 64 than exists below it.
Because the retainer element is supported at both ends and is merely moved out of the path of the plug 64, the movement of the element 56 may easily and rapidly be accomplished by rotating the handle 65 through a 90 degree are.
The retaining element 56 always remains entirely within the body of the apparatus, thereby eliminating the possibility of the operating pressure within the apparatus driving the retaining element from the apparatus as sometimes occurred in certain prior art plug injection apparatus.
What is claimed is:
1. Plug injector apparatus for use in earth well cementing or treating operations, comprising an elongated generally tubular body section having open upper and lower ends and inner and outer wall surfaces, means for closing said upper end, means for coupling said lower end to other hollow apparatus, a pumpable materials inlet, said inlet extending through the wall of said body section near the upper end of said body section, a pair of axially aligned bores, said bores being disposed below said materials inlet and perpendicular to the longitudinal axis of said body section, the longitudinal axis of the bores intersecting the longitudinal axis of the body section, one of said bores extending through the wall of said body section and the other bore extending partially through said body section, a plug retainer-member, said retainer member being a strap-like metal element which is semicircular in longitudinal cross sectional configuration, the diameter of the strap-like element being at least approximately the same as the inner diameter of the body section, and a pair of studs, each of said studs being rigidly secured to the outwardly facing part of said strap-like element at least near to an end of said element, one of said studs extending into each of said bores whereby said retainer member is pivotable about the longitudinal axis of said axially aligned bores, a retainer member actuating rod, said rod extending through said axially aligned bore which extends through said wall and being positively mechanically coupled to the stud in said bore whereby said retainer member rotates as said actuating rod is rotated, and means for rotating said actuating rod.
2. Apparatus in accordance with claim 1, wherein the inner wall of said body section has a recessed part adjacent to said bores which is adapted to receive said straplike element when said actuator rod is rotated to a predetermined position.
4 3. Apparatus in accordance with claim 1, wherein sealing means is provided between said actuator rod and the adjacent bore wall.
4. Apparatus in accordance with claim 1, wherein a second pumpable materials inlet extends through the wall of the body section below said bores.
References Cited by the Examiner UNITED STATES PATENTS 2,196,652 4/40 Baker 166-70 2,615,519 10/52 Carr 166--70 2,620,037 12/52 McClendon 166 -70 2,630,179 3/53 Brown 16670 2,664,163 12/53 Sch-mitter 16670 2,870,842 1/59 Hall 16670 3,125,116 3/64 Schaberg 150104.06
BENJAMIN HERSH, Primary Examiner.