Plunger tool for reciprocation pump

Abstract

A plunger tool and method relating thereto is designed to remove and insert plungers of a reciprocating pump such as during maintenance and other disassembly operations. The tool has a guide which receives and supports the plunger after removal from, and before reinsertion into, the pump. The tool also has a rack and pinion actuator for moving the plunger.

Claims

1. A method of supporting a plunger during maintenance or disassembly of a reciprocal pump, the method comprises: removing a cover plate from a cylinder opening on said pump; mating a guide to said cylinder opening of a cylinder containing said pump; attaching a first end of a rack to said plunger; and using a pinion to move said plunger from said cylinder onto said guide, wherein rotational motion of said pinion results in linear motion of said rack which pulls said plunger from said cylinder, and wherein said guide supports said plunger after said plunger is moved from said cylinder.

2. The method of claim 1, wherein said guide has a first end and a second end, and said mating is by screw mounting said second end into said cylinder opening.

3. The method of claim 2, wherein said guide has a bracket mount at said first end, and said pinion is a portion of a handle, and wherein the method further comprises: mating a hub attached to a gearbox with said bracket mount so as to keep said actuator stationary with respect to said guide; sliding a portion of said rack through said gearbox; inserting said pinion portion of said handle into said gearbox so that said pinion engages said rack; and turning said handle so as to move said rack and said plunger attached to said rack such that said plunger is moved from said cylinder onto said guide.

4. The method of claim 3, further comprising: after maintenance or disassembly of said reciprocal pump is complete, turning said handle so as to move said rack and said plunger attached to said rack such that said plunger is moved from said guide into said cylinder; disengaging said rack from said pinion and said gearbox; disengaging said rack from said first end of said plunger; and placing said cover plate over said cylinder opening.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a perspective view of a typical triplex reciprocating plunger pump.

(2) FIG. 2 is a perspective view of a plunger tool in accordance with one embodiment. The plunger tool is illustrated with a plunger but not connected to a pump.

(3) FIG. 3 is a cross-sectional view of the plunger tool illustrated in FIG. 2.

(4) FIG. 4 is a perspective view of a plunger tool in accordance with another embodiment.

(5) FIG. 5 is an exploded view of the plunger tool illustrated in FIG. 4.

(6) FIG. 6 is an enlarged illustration of the gearbox assembly used in the embodiment of FIGS. 4 and 5.

(7) FIG. 7 is a perspective view of the attachment end of a rack in accordance with some embodiments.

DETAILED DESCRIPTION

(8) In the description that follows, like parts are marked throughout the specification and drawings with the same reference numerals, respectively. The drawings are not necessarily to scale and the proportions of certain parts have been exaggerated to better illustrate details and features of the invention. In the following description, the terms inwardly and outwardly are directions toward and away from, respectively, the geometric axis of a referenced object. Where components of relatively well-known designs are employed, their structure and operation will not be described in detail.

(9) Referring now to FIG. 1, there is shown a typical triplex reciprocating plunger pump 10 with which the plunger tool of this disclosure might be used. Those skilled in the art will realize that the plunger tool will be applicable to other reciprocating pump designs. Plunger pump 10 has a power end 12 and a fluid end 14. The plunger pump assembly has three plunger cylinders or bores with centerlines 18a, 18b and 18c, each corresponding with a plunger 16a, 16b and 16c.

(10) Fluid end 14 includes a pump housing 22. The housing 22 comprises a front plane 24. Each of the three plunger cylinders terminate on front plate 24 in a cylinder opening, which are separately spaced across front plate 24. During normal operation of pump 10, each of the cylinders openings is closed by a cover plate or cap 20a, 20b and 20c.

(11) For maintenance of valves within the housing 22 and for maintenance or changing of the packing seals, it is necessary to remove caps 20a, 20b and 20c on the plunger cylinders located on front plate 24. Once the caps are removed, the plungers 16a, 16b and 16c in the cylinders have to be moved outward to allow appropriate access to the interior of the housing and allow changing of the packing seal and valves. As previously indicated, the plunger is heavy and large, and can be difficult to pull from the pump and reposition back in the pump.

(12) Turning now to FIGS. 2, 3 and 5 an embodiment of the current plunger tool 100 to facilitate removal and reinstallation of a plunger 16 from a reciprocating pump is illustrated. In order not to obscure features, FIGS. 3 and 5 do not show the plunger tool 100 connected to a plunger cylinder of a plunger pump; however, during normal use the plunger tool 100 would typically be connected, as explained below.

(13) Plunger pump 100 comprises a guide 110 having a first end 112, a second end 114 and a wall 116 extending from said first end to said second end. Wall 116 is configured to receive and support a plunger 16 removed from a pump. In some embodiments, wall 116 is a semi-cylinder so as to cradle or nest plunger 16 while still allowing access on the upper side of the guide 110.

(14) At first end 112, guide 110 has a bracket mount 118. At second end 114, guide 110 has a circular ring 120 which is configured so that a mating piece 122 can be attached thereto. Mating piece 122 can be releasablely attached such as by a ball bearing and groove releasable connection. Alternatively, mating piece 122 can be integrally formed as circular ring 120 or permanently secured to circular ring 120 by welding or use of steel dowels. Mating piece 122 is configured to engage and mate with the plunger cylinder opening on the plunger pump. Generally, this is done by screw mounting mating piece 122 into the cylinder opening using threads 124 on mating piece 122 and matching threads in the cylinder opening.

(15) An actuator assembly 126 is mounted at first end 112 of guide 110. As illustrated in the figures and as can be best seen from FIG. 6, actuator assembly 126 has a circular hub 128, which is configured to have an outer groove 130. Outer groove 130 mates with bracket mount 118 so that hub 128 can be removably mounted on guide 110. When mounted on guide 110, actuator assembly 126 is kept stationary with respect to guide 110. While the circular hub 128 is currently preferred, other mating shapes are within the scope of the invention.

(16) Connected to hub 128 is gearbox 132. Gearbox 132 serves as a housing to slidingly receive a rack 134 such that, when actuator assembly 126 is mounted on bracket mount 118, rack 134 extends longitudinally along wall 116 of guide 110 from first end 112 towards second end 114. Additionally, gearbox 132 serves to receive handle 140, which is a T-bar handle having a hand-grip bar 142 perpendicular to a pinion bar 144. Pinions or gears 146 are circumferentially spaced about pinion bar 144 (best seen from FIG. 5). As will be apparent from the figures, pinion bar 144 is received into gearbox 132 so that pinions 146 engage the gears 136 on the surface of rack 134 such that pinions 146 interact with gears 136 to control movement of rack 134 through gearbox 132. Thus, rotational motion of handle 140 results in linear motion of rack 134 along guide 110. Generally, handle 140 will be received in gearbox 132 so as to allow its removal; thus, allowing removal of rack 134 from gearbox 132. This removable assembly of the gearbox, rack and pinion allows for an easier connection of the rack to the plunger and of the guide to the cylinder opening.

(17) Rack 134 has an attachment end 138, which is configured to attach to plunger 16 such that, when attachment end 138 is attached to plunger 16, linear movement of rack 134 results in linear movement of plunger 16. Typically, the attachment end 138 and the end of plunger 16 have matching male and female mating shapes. After attachment end 138 is inserted into the end of plunger 16, it can be turned through a partial rotation such that it locks into plunger 16 until it is turned back through a partial rotation.

(18) As can be seen from FIG. 7, attachment end 138 can be comprised of a removable plunger adapter 152. Adapter 152 is removably attached to attachment end 138 of rack 134 so as to be easily replaced. For example, adapter 152 can have screw threads 154 which mate with matching screw threads in a bore (shown in FIG. 3) defined in attachment end 138, or another suitable attachment that allows easy removal. Adapter 152 has an attachment head 154 configured to attach to a plunger. Because adapter 152 is removably attached to attachment end 138, adapter 152 can be swapped out when a plunger requires a different size and/or different shape of attachment head.

(19) Returning now to FIGS. 2,3 and 5, actuator assembly 126 can also include a steel coupling 150 connected to gearbox 132 on the opposing side from hub 128. In the embodiment illustrated in FIGS. 2, 3 and 5, actuator assembly 126 is mounted on guide 110 such that gearbox 132 and coupling 150 extend out from first end 112 away from guide 110. FIG. 4 illustrates an alternative embodiment where actuator assembly 126 is mounted on guide 110 such that gearbox 132 and coupling 150 extend from first end 112 into guide 110.

(20) In operation, plunger tool 100 is used to remove and hold plunger 16 from a reciprocal pump. To remove the plunger, a cover plate 20a, 20b or 20c is removed from the associated cylinder opening of the cylinder housing a plunger 16. Next, guide 110 is mated to the cylinder opening by screwing mating piece 122 into the cylinder opening. Attachment end 138 of rack 134 is inserted into the matching orifice in the end of plunger 16 and turned to lock rack 134 to plunger 16.

(21) Either before or after rack 134 is locked to the plunger 16, hub 128 is positioned in bracket mount 118 so as keep actuator assembly 126 stationary with respect to guide 110. Also, at least a portion of rack 134 is slid through gearbox 132 so as to extend through gearbox 132, guide 110 and second end 114 of guide 110. Pinion bar 144 of handle 140 is introduced into gearbox 132 so that pinions 146 engage with gears 136 of rack 134.

(22) Next, handle 140 is turned thus rotating pinion bar 144. By the engagement of pinions 146 with gear 136, rotational motion of pinions 146 results in linear motion of rack 134. The longitudinal movement of rack 134 pulls plunger 16 from the plunger cylinder. As the plunger is pulled out of the cylinder, it is pulled onto wall 116 of guide 110, which supports plunger 16. If desired, plunger tool 100 can be left attached to the cylinder opening during maintenance or disassembly of the pump, and plunger tool 100 can continue to support and store plunger 16 during the maintenance or disassembly.

(23) After maintenance or disassembly of said reciprocal pump is complete, handle 140 is turned so as to move rack 134 and plunger 16 attached to rack 134 such that plunger 16 is moved from guide 110 into the plunger cylinder. Once the plunger is positioned in the cylinder, rack 134 can be disengaged from plunger 16 by turning attachment end 138. In some embodiments, rack 134 is slid out of gearbox 132 and actuator assembly 126 is removed from guide 110 prior to disengagement of rack 134 from the plunger. After this disengagement, the cover plate is reinstalled over the cylinder opening.

(24) The above elements of the tool as well as others can be seen with reference to the figures. From the above description and figures, it will be seen that the present invention is well adapted to carry out the ends and advantages mentioned, as well as those inherent therein. While the presently preferred embodiment of the apparatus has been shown for the purposes of this disclosure, those skilled in the art may make numerous changes in the arrangement and construction of parts. All of such changes are encompassed within the scope and spirit of the appended claims.