US2362750A - Pumping apparatus - Google Patents

Description

' 1944. J. 'r. HAYWARD ruirme APPARATUS Filed June 26. 1942 INVENTOR JOHN T. HAYWARD A TTORNEV UNITED STATES PATENT OFFICE PUMPING APPARATUS John T. Hayward, Tulsa, Okla.

Application June 26, 1942, Serial No. 448,603

6 Claims.

This invention relates to pumps and particularly to pumping mechanism for handling fluids carrying solids in suspension.

When pumping fluids carrying solids or semisolids in suspension, such as clay or mud slurries commonly employed in drilling oil and gas wells by the rotary method, it is often desirable to pump a small portion of the mud to mud analysis or testing devices. Normally, small pumps are employed and the valves and ports of such pumps become clogged very quickly by the particles of the drill cuttings, cotton seed hulls, celotex and other addition materials commonly added to drilling muds. When screens or strainers are placed over the ends of the pump suction pipes, such screens, if fine enough to exclude the undesirable materials, quickly become clogged by such materials and render the pump inoperative.

The principal object of this invention is to provide an improved form of pumping mechanism whereby the suction screens are substantially kept clear of the undesired materials and clogging hindered, while the pump continues to deliver the desired stream of mud fluid relatively uninterruptedly.

In accordance with a general embodiment of this invention, suitable means is provided in operative association with the pump suction mechanism, which has screened inlets, whereby reversal of the fluid flow back through the suction pipe and screen may be effected either continuously or intermittently as may be desired, in various ways, several of which are described hereinafter by way of example.

Other objects and advantages of this invention will become apparent from the following detailed descr ption. when read in conjunction with the accompanying drawing which illustrates several useful embodiments in accordance with this invention.

In the drawing:

Fig. 1 illustrates an arrangement of apparatus constituting one embodiment in accordance with an embodiment of this invention;

Fig. 2 is a sectional elevation of a pumping mechanism in accordance with another embodiment of this invention; and

Fig. 3 illustrates still another embodiment in accordance with this invention.

Referring to the drawing and to Fig. l in particular, the numeral I designates a container for fluid to be handled by the pump. Container I may be a tank. ditch or pit in which the fluid is stored or through which the fluid may be flowing. The inlet end of a suction pipe 2 is immersed in the body of the fluid in'container I and is covered by scr ee n 3 having a mesh fineness adapted to eiitilfid sblid or semi-solid particles of undesired size from the suction pipe. The opposite end of suction pipe 2 is connected to a pump cylinder 4 having a discharge pipe 5. Pump cylinder 4 may be of any suitable or conventional design and may be a reciprocating, rotary or entigf ugal p u m p which is driven by mean 0 aft 6 connected to any suitable power source (not shown). A branch conduit 1 is connected into suction pipe 2 at any suitable point intermediate the ends of the suction pipe. Reciprocably mounted in branch conduit I is a, plunger 8 which is movable through a packing gland 9 arranged in the outer end of branch conduit I to form a fluid tight seal between the plunger and the branch conduit. A crank arm II] has one end pivotally connected at I I to the outer end of plunger 8 and its other end pivoted at I2 to an eccentric crank I3 which is rotated by a shaft I4, which may be driven by any suitable power source (not shown). Rotation of crank I3 reciprocates plunger 8 in branch conduit I, the stroke being limited by the throw of crank I3.

The above described mechanism is operated in the following manner: Pumping is begun in the usual manner with pump cylinder 4 drawing fluid from container I through screen 3 and suction pipe 2 and discharging the fluid through discharge pipe 5 to the desired place of delivery (not shown). the pumping operation, or as soon thereafter as screen 3 shows signs of becoming clogged, plunger 8 is set in operation. The reciprocating movement of plunger 8 in branch conduit I produces a reverse pulsation in the stream of fillid llllg yeling roug e suc iorfp'ipe'iifdbfieacli inward stroke of the plii rig'fsbifie of the fluid is forced back through the suction pipe and screen under sufiicient pressure to blow fromme sgr egp any clogging material vmh'Ynay have collected thereon. As indicated previously, crank I3 operating plunger ,8 may be driven by any suitable power source independent of pump 5, or it may be drivingly connected in any convenient and suitable manner to shaft 6, as indicated by the broken line Plunger 8, branch conduit I and crank I3 constitute a pulsating means and the diameter of plunger 8 and its rate of displacement must be such that when its rate of displacement is a maximum, it will exceed the rate of delivery of pump 4. Under these conditions the reciproca- Simultaneously with the beginning of to nman auygrtqsia amane fl vqfiluiqw keepin th suct on pipe and Q stresses..- sj nclear. In this embodiment, a pump body |6 of generally tubular form and horizontally disposed, is provided at one end with a suction valve chamber I1 and at the other end with a discharge valve chamber l8. Suction valve chamber I1 is provided with an inlet connection l9 which is connected to a suction pipe, such as suction pipe 2 of the previously described embodiment. Inlet connection I9 communicates with the interior of chamber through an upwardly opening circular port 20 provided with an annular seat 2| upon which a conical valve 22 is seated and adapted to open and close the port 20 by vertical movement relative thereto. The top of suction valve chamber I! is closed by a cover plate 23 arranged directly above valve 22 and provided with a downwardly extending boss 24 forming a stop to limit the upward travel of valve 22 relative to seat 2|. Discharge valve chamber I8 is provided with a discharge connection I81: and communicates with the interior of pump body l6 through a circular port 25 provided with an annular seat 26 and a valve 21. A cover plate 28 is arranged above valve 21 and is also provided with a downward extension 29 to limit the upward travel of valve 21, The degree of clearance between valve 22 and boss 24 is designed to be substantially greater than its normal degree of clearance in relation to that between valve 21 and extension 29.

Connected to an intermediate portion of pump body l6 and extending at right angles thereto is a cylinder 30 having a plunger 3| slidably disposed therein. The outer end of cylinder 30 is closed by a packing gland 32 which forms a fluid tight seal about the body of plunger 3|. The outer end of piston 3| i provided with a piston rod 33 for connection to any suitable power mechanism (not shown) adapted to reciprocat piston 3| in cylinder 30.

In operation, reciprocation of plunger 3| produces corresponding action of valves 22 and 21. That is, on the out-stroke of the plunger, suction is created within body l6 raising valve 22 and admitting fluid to the interior of the cylinder 30 from suction pipe 2, and on the in-stroke, the resulting compression forces the fluid to lift valve 21 for discharge through outlet l8a. By providing a greater than normal degree of clearance between suction valve 22 and its stop 24, the closing of suction port 2| will be delayed, with the result that the compression stroke of piston 3| will force some of the fluid in the pump body back through the suction port and thence 1 through suction pipe 2 and screen 3 and thereby I dislodge any material which has adhered to the kscreen.

The degree of clearance above valve 22 will preferably be so designed that the resulting seating lag will only be sufficient to permit a portion of the fluid to flow in reverse, the remainder being discharged through discharge port 25 and outlet connection |8a to thereby provide a continuous discharge of fluid from the cylinder 39 may be employed, such as gmveni'ional ball mnemmhelikew Also meaningsrocating pumps may be adapted to operate in acccfidance vTitH this embodiment.

The embodiment of Fig. 3 illustrates another embodiment of the arrangement illustrated in Fig. 2 and described above. In accordance with the embodiment of Fig. 3, an armature 34 of an electromagnet 35 is threadedly inserted through the cover plate 23 and extends into suction valve chamber I1, where the inner end of armature 34 forms a stop for valve 22 at the normal distance therefrom. Normally, therefore, suction valve 22 will operate at normal timing without lag and no back-flow will occur. The electromagnet is connected by conductor leads 36 and 31 to a battery 38 or other suitable source of current. A switch 39 is provided in the circuit of the electromagnet. In this embodiment, cover plate 23 will be constructed of brass or other nonmagnetizable material, while valve 22 will be constructed of suitable magnetizable material such as iron or steel.

With this embodiment, when it is desired to clear the suction pipe and screen, switch 39 is closed thereby energizing armature 34 with the result that, when valve 22 is raised from its seat during the suction stroke of the pump and comes up against the end of armature 34, it will be held against the armature by magnetic attraction and will remain off of seat 2| as long as current flows through the winding of the electro-magnet. With suction valve 22 held from its seat, the discharge stroke of the pump will cause reverse flow of fluid through the suction passageways, producing the previously described screen-clearing action. The electromagnet may be energized intermittently or at suitable regular intervals, or whenever the screen begins to become clogged.

It will be understood that various changes and modifications may be made in the details of the apparatus herein described within the scope of the appended claims but without departing from the spirit of this invention.

What I claim and desire to secure by Letters Patent is:

1. In pumping apparatus wherein a pump suction is provided with a suction valve and with a screen for straining extraneous matter from the fluid being pumped, the improvement for hindering clogging of the screen comprising, means associated with the suction valve of the pump to delay the normal operating period thereof whereby to produce reverse flow of said fluid through said screen.

2. In pumping apparatus wherein a pump suction is provided with a screen for straining extraneous matter from the fluid being pumped, the improvement for hindering clogging of the screen comprising, means associated with the suction of the pump and operative during the normal operation of the pump to cause a portion of the fluid entering the pump suction to reverse its direction therein and discharge through said screen.

3. In pumping apparatus wherein a pump suction is provided with a screen for straining extraneous matter from the fluid being pumped, the improvement for hindering clogging of the screen comprising, plunger means associated with the pump suction and operative therein to force a portion of the fluid entering the pump suction to reverse its direction and discharge through said screen.

4. Pumping apparatus comprising, in combination with a pump having suction and discharge valves and a suction pipe having a screen associated therewith, means associated with said suction valve for extending the normal off-seat period thereof to thereby cause a portion of the fluid passing the suction valve to reverse its direction and discharge through said screen during the discharge stroke of the pump.

5. Pumping apparatus comprising, in combination with a pump provided with a suction pipe having a screen associated therewith, an auxiliary cylinder communicating with said suction pipe between said pump and said screen, and a plunger reciprocable in said cylinder to cause a portion 15 of the fluid being drawn through said suction pipe and said screen to reverse its direction of flow and discharge through said screen.

6. In a pump having normally operating mechanism and whose suction is provided with a suction valve and with a screen for straining extraneous matter from the fluid being pumped, the improvement for hindering clogging of the screen comprising, means in addition to but associated with the operating mechanism of the pump, said means being operative during the normal continued pumping operation of the pump to effect reverse flow of said fluid through said screen.

JOHN T. HAYWARD.

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