US3228343A - Self-priming pump - Google Patents

Description

Jan. 11, 1966 P, J. ANTON ETAL 3,223,343

SELF-PRIMING PUMP Filed May 25, 1964 ATTORNEY United States Patent Ofiice 3,223,343 Patented Jan. ll, 1966 3,228,343 SELF-PRMING PUMP Paul J. Anton, Downey, Calif., and James W. Wyche, Belmont, New Iberia, La., assignors to US. Pumps, Inc., Los Angeles, Calif., a corporation of Delaware Filed May 25, 1964, Ser. No. 369,955 5 Claims. (Cl. 103-413) This invention relates to a vertical, multi-stage pump for unloading and stripping liquid products for barges, tank ships and shore installations, and has for an object to automatically prime itself in the event of interruption of flow in the suction line, thereby having the ability to strip compartments completely without the aid of costly auxiliary equipment and with high speed and efficiency.

Another object of the invention is to provide a pump, as above characterized, that is exceptionally compact and easy to maintain in operative condition, due to its simplicity of construction.

A further object of the invention is to provide a selfprirning pump with ability to pass considerable quantities of air, create and maintain comparatively high vacuum in the suction line, and, therefore, obviate formation of vapor locks and provide highly efiicient stripping ability.

A still further object of the invention is to provide a self-priming pump, as above referred to, that embodies simple, fool-proof, and highly efiicient means that is responsive to loss of discharge pressure to institute a repriming operation automatically.

This invention also has for its objects to provide such means that are positive in operation, convenient in use, easily installed in a working position and easily disconnected therefrom, economical of manufacture, relatively simple, and of general superiority and serviceability.

The foregoing objects of the invention are realized in a pump that is vertically mounted in a barrel that con stitutes a well to which, intermediate its ends, is connected a suction flow line from a tank or tanks on barges, ships, or shore installations. The pump is formed in two stages with a connecting chamber, and the second or upper stage of the pump discharges into a line at the upper end. The above general organization is provided with means to automatically prime the pump and which comprises a liquid-recirculating valve in the lower portion of the discharge line, and an air release valve in said line above the recirculating valve. Said two valves automatically act, upon breaking of suction in the suction flow line, to effect a transfer of liquid from the discharge line to the bottom of the Well. One valve opens, due to loss of pumping pressure, and the liquid from the discharge lines empties therethrough as the other valve opens and releases air into said line to allow such liquid transfer. This liquid in the well primes the pump to effect re-establishment of normal discharge flow. A check valve in the discharge valve automatically closes upon loss of discharge pressure, limiting the transfer of liquid to the well to the liquid present in the portion of the discharge line that is between the pump and said check valve.

The invention also comprises novel details of construc tion and novel combinations and arrangements of parts, which will more fully appear in the course of the following description and which is based on the accompanying drawing. However, said drawing merely shows, and the following description merely describes, one embodiment of the present invention, which is given by way of illustration or example only.

In the drawing, like reference characters designate similar parts in the several views.

FIG. 1 is a vertical sectional view of a self-priming pump according to the present invention.

FIG. 2 is an enlarged vertical sectional view showing the portion of the discharge line adjacent the pump and the self-priming means of the present invention applied thereto.

The self-priming pump that is illustrated comprises, generally, a well barrel 5 having a port 6 for connection to a suction line, a pump unit 7 vertically disposed in said barrel, a discharge conduit 8 extending upwardly from the pump unit and discharging into a line 9 with a check valve 10 interposed between said conduit and line to prevent back flow to the conduit 8, a mounting unit 11 closing the top of the well barrel 5, connected thereto and supporting the pump unit 7, a drive 12, sup ported by said unit 11 and having a driven shaft 13 connected to and driving the pump unit, and means to prime said pump with liquid in the conduit 8 and comprising a liquid recirculating valve 14 and an air release valve 15, both mounted on the conduit 8, the former below the latter.

The well defined by the barrel 5 is of ample size to hold all of the liquid that is transferred from the discharge conduit 8. The port 6 is located above the level of such pumppriming liquid.

The pump unit 7 preferably comprises a lower first stage pump 21 which comprises an impeller pump that has an inlet provided with a suction bell 22 open to the bottom of the well, a second stage pump 23 that comprises a plurality of impeller pumps 24, above the first stage pump, and an air chamber 25 connecting the top of pump 21 to receive the outlet thereof, and the bottom of the second stage pump 23, to conduct fluid from the first to the second stage. In a conventional manner, an air vent line 26 connects the two pump stages and the chamber 25. The impellers of the above-described pumps are all mounted on the shaft 13, the latter extending through the chamber 25, as shown.

It will be understood that liquid in the bottom of the well, during normal operation of the pump unit 7, is drawn upwardly through the bell 22 by the first-stage pump 21, displaced into and upwardly through the chamber 25 and, finally, received by the second-stage pump 23 and forced thereby into and upwardly through the conduit 8, past the check valve 10, and outwardly through the discharge pipe 9.

The mounting unit 11 is provided with a mounting plate 27 that, by being connected to a top flange 28 on the well barrel 5, closes the well. This unit includes an elbow 29 that is at the upper end of the conduit 8 and is formed with an upper extension 30 on which the motor 12 is mounted. The shaft 13, driven by said motor, extends through said extension 30, the elbow 29, the conduit 8, and through the pump unit 23 to drive the impellers thereof.

So long as there is a solid column of liquid in the suction line to the port 6, the lower part of the well covering said port, and though the pump unit 7, conduit 8, elbow 29, and the check valve 1!), liquid will continue to flow to the discharge pipe 9. The self-priming means comprising the valves 14 and 15 automatically react to a change in this condition in which the change causes a reduction of pressure in said conduit as a result or" a loss of suction in the suction line to the port 6.

The valve 14 is mounted on a boss 31 adjacent the lower end of the conduit 8 and is shown as a body 32 connected to said boss, a central passage 33 in said body connecting the interior of the conduit with the well, said body having a valve seat 34 around said passage and facing the interior of the conduit, a valve disc 35 operatively associated with the valve seat 34 and provided with a stem 36 guided in a 3 bearing 37 formed in a bridge extension of the body 32, and a spring 38 around the stem 36 between said disc 35 and bearing 37 to normally bias the disc to spaced relation with the valve seat 34 to open the valve. It will be understood that pressure in conduit 8, greater than the force of spring 38, will cause said valve to close.

The valve 14 is located on the conduit 8 so that the volume of liquid between said valve and the check valve 10 is large enough to provide liquid to the level 20 in the well, when the valve is opened to allow discharge from the conduit into the well.

The valve 15 is mounted on a boss 39 at a level above the boss 31. Said valve is similar to valve 14 as to body 32, passage 33, valve seat 34, valve disc 35, stem 36, and bearing 37. However, the disc 35 is biased by a spring 40 to a normally spaced position from the valve seat 34 to open said valve 15. It will be understood that reduction of pressure in the conduit 8 such that the pressure in the well overcomes the bias of the spring 40, will cause said valve to open.

OPERATION The pump starts its operation with the liquid in well 5 to the level 20. The motor or engine that operates the drive 12 is started to drive the pump unit 7, causing this liquid to be drawn-upwardly through the bell 22 into the chamber 25, as shown. Since there is no pressure in the conduit 8 during this first stage of the pumping operation, the recirculating valve 14 is retained open by its spring 38. The decrease of pressure in the Well due to its initial step of the operation enables the spring 40 to close and maintain valve 15 closed. The suction line connected to port 6 is also subject to this suction, producing a rise of the liquid therein toward the port.

As the level 41 in the chamber 25 rises toward the upper pump stage, the valves 14 and 15 remain in the above-described positions and the increasing suction in the well causes the flow in the suction line to overflow the port 6 and enter the well, thereby supplying a continuous and solid flow through the entire pump unit 7. This flow creates pressure in the conduit 8 and a corresponding suction in the well above the level of the port 6. As a consequence, the valve 14 will close. Thus, both valves 14 and 15 are closed during this condition, which is the normal operating condition of the pump.

The pump operates in this normal manner until, for whatever reason, the suction is broken in the line leading to the port 6, usually when the tank being emptied through said line is completely stripped. At this time, the pump unit 7 runs out of liquid to pump and the conduit 8 loses its pressure. The'spring 38, which has a force greater than that of spring 40, opens valve 14, dumping the liquid in conduit 8, between said valve and the check valve 10, into the well. The pressure in said conduit, accordingly, decreases. Then, as the level of liquid in said conduit lowers to uncover the valve 15, a substantial suction builds up in the conduit, causing the valve 15 to open against the light bias of its spring 46. Air is, therefore, released from the well into the conduit 8 above the liquid being transferred to the well to replace said liquid, and allowing the liquid transfer to continue until the conduit has emptied to the level 42. At this time, the level 20 has been achieved, sealing the first stage pump 21, and the cycle of priming operation, as begun above, is completed. Thereafter, the pump operates in its usual manner until the suction line is again broken and repriming is instituted.

While the foregoing has illustrated and described what is now contemplated to be thebest mode of carrying out the invention, the construction is, of course, subject to modification without departing from the spirit and scope of the invention. Therefore, it is not desired to restrict the invention to the particular form of construction illustrated and described, but to cover all modifications that may fall within the scope of the appended claims.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

1. In a self-priming pump that comprises a well provided with a suction inlet from a source of liquid, having a pumping unit in said well disposed to draw liquid from the bottom of the well, and having a discharge conduit extending from and above the pumping unit and discharging into an outlet, a valve to check return flow being interposed between the conduit and the outlet,

(a) means to provide pump-priming liquid in the bottom of the well comprising (b) a recirculating valve in the conduit adjacent the upper end of the pump, retained closed by the pressure of the liquid moved upwardly through the conduit during liquid pumping and opening automatically upon lowering of the pressure of said liquid, to effect transfer of liquid in the conduit to the bottom of the well, and

(c) a normally-closed air release valve in the conduit spaced above the recirculating valve, and opening under suction created in the conduit above the liquid during transfer thereof to supply the conduit with air to replace the liquid transferred therefrom.

2. In a self-priming pump according to claim 1, both the recirculating and the air release valves being resiliently biased, the former to a normally open position and the latter to a normally closed position.

3. In a self-priming pump according to claim 1, the liquid capacity of the conduit having the recirculating and air release valves being sufficient to provide priming liquid in the well to a level that seals the lower portion of the pump and, thereby, enables the same to return the liquid upwardly into the conduit.

4. Means to release priming liquid from a pump-propelled flow of said liquid through a vertical discharge conduit, said means comprising:

(a) a recirculating valve in the conduit adjacent its lower end and retained closed by pressure in the conduit, and

(b) a normally closed air release valve in the conduit spaced above the recirculating valve,

(c) the recirculating valve having a resilient bias to open and release the liquid in the conduit upon lowering of the pressure therein, and

(d) the air release valve having a spring to hold the same closed and yielding to suction in the conduit induced by said release of liquid to vent the conduit above the level of the water being released.

5. Means according to claim 4 in which the recirculating valve is biased by a spring that has greater force than the spring of the air release valve.

References Cited by the Examiner UNITED STATES PATENTS 1,830,923 11/1931 Bradford 103 113 2,219,635 10/11940 Ralston. 2,902,940 9/1959 Meyer et al 103-413 3,211,102 10/1965 Keehan 103-413 SAMUEL LEVINE, m ry Examiner.

Claims (1)

1. IN A SELF-PRIMING PUMP THAT COMPRISES A WELL PROVIDED WITH A SUCTION INLET FROM A SOURCE OF LIQUID, HAVING A PUMPING UNIT IN SAID WELL DISPOSED TO DRAW LIQUID FROM THE BOTTOM OF THE WELL, AND HAVING A DISCHARGE CONDUIT EXTENDING FROM AND ABOVE THE PUMPING UNIT AND DISCHARGING INTO AN OUTLET, A VALVE TO CHECK RETURN FLOW BEING INTERPOSED BETWEEN THE CONDUIT AND THE OUTLET, (A) MEANS TO PROVIDE PUMP-PRIMING LIQUID IN THE BOTTOM OF THE WELL COMPRISING (B) A RECIRCULATING VALVE IN THE CONDUIT ADJACENT THE UPPER END OF THE PUMP, RETAINED CLOSED BY THE PRESSURE OF THE LIQUID MOVED UPWARDLY THROUGH THE CONDUIT DURING LIQUID PUMPING AND OPENING AUTOMATICALLY UPON LOWERING OF THE PRESSURE OF SAID LIQUID, TO EFFECT TRANSFER OF LIQUID IN THE CONDUIT TO THE BOTTOM OF THE WELL, AND (C) A NORMALLY-CLOSED AIR RELEASE VALVE IN THE CONDUIT SPACED ABOVE THE RECIRCULATING VALVE, AND OPENING

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