~Z~L38~31 ~1ell Purnp Shield This invention relates to a shield for insertion in a well casing to protect the well pump.
After digging a well, it is known to sink a well casing below the water table, connect a pump pipe and an electric cable to a pump, and lower the pump into the water in the casing. It is known to mount a well cap over the upper end oE the well casing to prevent foreign o~ects from penetrating into the well casing. Some well caps have an opening for the electrical cahle to thè pump and another opening for the pump pipe. When a pitless unit is used, the well cap does not have an opening for the pump pipe as the pipe terminates at the pitless unit. The well cap may be below ground surface, in which case a vent tube from the surface connects through the cap with the interior of the casing to prevent the pump from drawing a vacuum above the water seeping into the bottom of the casing.
In consequence of the above arrangements there are bolts, nuts, steel plates and other parts on t.he well cap and pitless unit which could fall into the well casing.
~urther, during insertion of a pump into the well, or withdrawal therefrom, rocks or parts could fall into the well casing.
Material falling into the well casing could lodge be~ween the pump and well casing thereby jamming the pump in the casing. Dislodging the pump often requires significant force which may usually only be applied by tugging on the pump pipe. Since plastic pump pipe is now used in the majority of wells, such force can break the pipe resulting dm~
in the pump being lost down the well.
The present invention seeks to overcome this problem with the prior art well arranqements. Briefly stated, the present invention is an electrical well pump shield for insertion in a well casinq in order to shield an electrical well pump from objects falling into the well casing, comprisinq; a first hollow cylinder havinq an out-side diameter conforming substantially to the inside diam-eter of the well casinq; a second hollow cylinder integ-rally formed at one end of the first hollow cylinder and protrudinq therefrom, the cylinders havinq a common lonq-itudinal axis, and the second hollow cylinder havinq a smaller outside diameter than the outside diameter of the first hollow cylinder and an inside diameter conforminq substantially to the outside diameter of a pump pipe for the electrical pump at most two passaqes throuqh mater-ial inteqrally forminq the second cylinder with the first cylinder the passages spaced radially inwardly from the outside diameter of the first cylinder.
In the drawinqs which illustrate the embodi-ments o the invention:
Fiqure 1 is a perspective view of the well pump shield of this invention;
Fiqure 2 is a schematic view of the well pump shield installed in a well casing.
Referrinq to Figure 1, the well pump shield 1 consists of a larger diameter hollow cylinder 2 inteq-rally formed by means of base 4 with a smaller diameter hollow cylinder 3 so that the shield is a cup-shape~
element, with the smaller diameter cylinder protruding vtd/ ~
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from the base of the cup. The two cylinders have a common lonqitudinal axis. The end of cylinder 3 remote from cylinder 2 has a smaller outer diameter than the end proximate cylinder 2. A hose clamp S is positioned over this smaller outer diameter end.
Base 4 is convex; an openin~ 6 is provided throuqh the base and, optionally, a second openin~ 7 is also provided .
- 2a -vtd/ ~
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through the base opposite openi,ng 6.
Pump shield ]. may be rnade in various sizes and of any suitabl.e material, for example plastic, steel, wood, or rubber.
Figure 2 shows the well pump shield of I`igure 1 installed in a well casing 8. rrhe shield is oriented so that the larger diameter cylinder 2 is above the smaller diameter cylinder 3. The outer diameter of cylinder 2 is selected so that it is substantially the same as the inner diameter o the well casing. If the cylinder is madè of a flexible material, an interference fit between the cylinder and well casing is possible. Otherwise, the outer diameter of cylinder 2 should ~e slightly less than tl,e inner diameter of the well casing.
Pumpp'ipe 9 passes through cylinders 2 and 3. The inner diameter of cylinder 3 is selected to be slightly greater than the outer diameter of pump pipe 9 so that the shield may be slid onto the pump pipe and so that hose clamp 7, when tightened, causes the end of cylinder 3 remote from cylinder
2 to en~age the pipe and thereby hold the shield in place~
Submersible pump 10 is affixed to the lower end of pump pipe 9. Electric cable 11, which is connected to a source of power (not shown) passes through well cap 12 and opening 6 in pump shield 1 and is operatively connected to electrically actuated submersible pump 10.
Pump pipe 9 terminates at its upper end in pitless unit 13. The pitless unit directs water pumped through the pipe into water pipe 14 from whence it passes to a point of storage or use. A cable 15 is secured at its upper end to the well cap and at its lower end to the pitless unit 13.
dm: i - 3 q3~ 0 The well pump shield is preferrably located ahout ~' below the pitless unit.
It is seen that to install the shield, it is slid over the pump pipe to a distance of about ~' below one end. The hose clamp 7 is then tightened to secure the shield at this point. The pitless unit is at-tached to this end of the pipe and a cable is attached to-the unit. The pump is attached to the other end of the pump pipe and an electric cable is run to the pump through opening 6 in the shield. This assembly ln is lowered into the wall casing, pump first. The pitless unit is maneuvered into place and attached to the side of the we~l casing; the well cap is then installed with the cable 15 attached thereto and the electric cable passing therethrough.
Thereafter, the well cap may be covered over as long as a vent is provided from the interior of the wall casing to the surface.
Although not shown in Figure 2, a rope may be attached between the pump and well cap, such a rope passes through the optional hole 7 in shield 1.
. Alternatively, pitless unit 13 may be omitted, in such case pump pipe 9 extends to the top of the well casing and through an opening provided in the well cap. In this embodiment it is preferred that the shield be located 12' below the top of the well casing.
In either embodiment, as the installed shield is located an appreciable distance down the well, it could not easily be removed by, for example, children in play. Further, foreign articles, such as rocks, nuts, bolts, and steel plates falling from the well cap or pitless unit fall into the 30 cup-shaped shield and do not lodge between the pump and dm~
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well casing thereby jimming the pump in the casing. When the pump is brought to the surface at a future time, the shield may be emptied of any such foreign articles.
Also, duxing installation of the pump, the shield, once in the casing, prevents foreign articles whlch may fall into the casing during installation from reaching the pump.
~ hus, it is seen -that the pump shield guards against the pump becoming~jammed in the well casing and, hence, may avoid loss of the pump.
It will be apparent to those skilled in the art that the pump shield could be a disc-shaped element with a central opening and with an outer diameter substantially equal to the inner diameter of the well casing. A smaller diameter hollow cylinder could be integrally formed with the disc-shaped element to give the element stability and to permit the shield to be attached to the pump pipe.
In place of the integrally formed smaller diameter cylinder, other means could be provided to attach the shield to the pipe such as a separate supporting clamp attached to the pipe.
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