US3804556A - Slurry pump - Google Patents

Abstract

The invention is a pump adaptable to pump mud and silt or other slurried material. The pump comprises two cylinders. While one is pumping, the other is filling with mud. Each cylinder has a piston (preferably floating) in it which separates the mud from the hydraulic fluid. The hydraulic fluid is oil or is essentially water containing soluble oils for lubrication. The hydraulic fluid is pumped out of one cylinder and into the other. This operation draws the floating piston away from one end of the first cylinder, thereby drawing in the mud under vacuum plus the differential barometric head. At the same time an equal volume of hydraulic fluid is pumped into the other cylinder, causing the piston therein to eject mud through a mud line. At the moment that one piston reaches one extreme of its stroke, the other one reaches the other extreme of its stroke. At this same moment, a switching mechanism changes the direction of flow of the hydraulic fluid between the two cylinders. Also, at this same moment, the positions of the two cylinders relative to a discharge line opening are shifted so that the cylinder which has just filled with mud becomes aligned with the mud line to shore and it begins its exhaust stroke. This fluid reversal and shifting will generally take place several times per minute. To change the relative positions of the cylinders and the mud line, the mud line may be shifted from one cylinder to the other, or the cylinders may be shifted while the mud line remains stationary.

Description

United States Patent 1191 Katzer et a].

1451 Apr. 16, 1974 SLURRY PUMP [75] Inventors: Melvin F. Katzer, Danville; Willis G.

Routson, Walnut Creek, both of [21] Appl. No.: 293,116

[5 7] ABSTRACT The invention is a pump adaptable to pump mud and silt or other slurried material. The pump comprises two cylinders. While one ispumping, the otheris filling with mud. Each cylinder has a piston (preferably floating) in it which separates the mud from the hydraulic fluid. The hydraulic fluid is oil or is essentially water containing soluble oils for lubrication. The hydraulic fluid is pumped out of one cylinder and into the other. This operation draws the floating piston away from one end of the first cylinder, thereby draw- [52] US. Cl 417/390, 417/516, 417/517, ing i the mud under vaCuum plus the diff ti l 417/900 barometric head. At the same time an equal volume of [51] Int. Cl. F04b 9/08, F04b 7/00 hydraulic fluid i pumped int the other cylinder, Fleld of Search 117/517, 900, 390, causing the piston therein to eject mud through a mud 117/122 149 line. At the moment that one piston reaches one ex- I I v i I treme of its stroke, the other one reaches the other ex- 6] References Clted treme of its stroke. At this same moment,'a switching UNITED STATES PATENTS mechanism changes the direction of flow'of the hy- 2,796,032 6/1957 Ballert 417 900 drflulic fluid betweenlheiwo cylinders- A180, at this 2,857,852 10/1955 Carignani et al. 417/122 same moment, the positions of the two cylinders rela- 3,298,322 1/1967 Sherrod 417/517 tive to a discharge line opening are shifted so that the 3,630,638 12/1'971 Huso 417/390 cylinder which has just filled with mud becomes AIltOSh 1 1 aligned the mud to shore and its ex- 3,682,575 8/1972 Guddal 417/517 haust stroka i fluid reversal and i g will FOREIGN PATENTS ORAPPLICATIONS erally take place several times per minute. To change 1,214,342 12/1970 Great Britain 417/517 felatwe 9 f cylinders m 1 line, the mud line maybe shifted fromone cylmder to Primary Examiner wllliam L Freeh the other, or the cylinders may-be shifted while the Assistant Examiner-Richard E. Gluck mud remams stlanonary' Attorney, Agent, or F1rm--Earl D. Ayers 6 Claims 5 Drawing Figurejs f/ybraQ/fc pump t 5 5 r em 54 1; f 5 Con/reflex SLURRY PUMP BACKGROUND OF THE INVENTION This invention relates to slurry pumps and particu- 5 larly to multiple cylinder-type which are adapted to operation while submerged.

Most slurry or mud pumps are either centrifugal, diaphragm or piston pumps. The centrifugal pump is the only one of these three types that does not require some kind of check valve system. Check valves are subject to fouling especially by sticks, wires, grass, etc. However, a centrifugal pump is a high speed pump which cannot operate efficiently at low rotational speeds. Therefore, they cannot operate efficiently at low rotational speeds. Therefore, they cannot efficiently be used for pumping extremely viscous materials such as muds and sediment.

One other type of pump that has been used successfully is a large diameter roller pump. It can pump heavy slurries and has no valves to become plugged with debris. However, any tin cans or other solid debris may lodge under the roller and could easily become stuck at that point or might cut or damage the tubing.

As mentioned, both piston and diaphragm pumps require the use of check valves which are subject to fouling and represent a constriction in the line.

OBJECTS OFTI-IE INVENTION A principal object of this invention is to provide an improved slurry pump.

Another object of this invention is to provide an improved, simple to. construct and operate, slurry pump.

A further object of this inventionis to provide an improved slurry'pump which is" well adapted to operate with slurries which are viscous and/or contain debris.

STATEMENT OF THEINVENTION In accordance with this invention, there is provided aslurry pump comprising a piston inside each of one or more cylinders. One end of each cylinder is open to receive or discharge the mud or slurry. The other ends of the cylinders are connected to a hydraulic system which alternately applies suction and then pressure. The piston preferably floating separates the hydraulic system from the mud system. During the suction stroke, the piston moves away from the mud source and mud or other slurry is drawn into the cylinder. When the end'ofthe stroke is reached, the negative pressure is reversed to a positive pressure and the floating piston is pushed toward the open end of the cylinder. At the same moment the entire cylinder assembly (or the receiving end of the discharge line) is shifted so that the open end of the cylinder is now aligned with a discharge pipe that leads to a spoils area. Ideally the discharge pipe has the same diameter as the cylinder so that any debris that enters the cylinder can flow all the way to the spoils area without plugging the discharge line. Once the piston goes to the end of its pressure stroke, both the direction of flow of the hydraulic fluid and the relative positions of the cylinder and discharge. line are again reversed.

Two such cylinders mounted adjacent to each other permit the use of a common discharge pipe and two separate but adjacent suction ports. When either piston reaches the end of its suction stroke, either a proximity switch or a sudden increase in the negative pressure signals the hydraulic system to reverse and also signals the shift in the location of the mud discharge line relative to the cylinder end(s).

Instead of a lateral shift, it is also feasible to have the cylinders mounted on a common axis on opposite sides of a spool pierced by axially arcuate bores of the same diametrical size as the cylinders. The spool rotatingly slidesor shifts to alternately connect the cylinders and discharge lines through said bores. Preferably, the spool and cylinder axes are at right angles to each other in a horizontal plane and the discharge and intake line openings are respectively above and below the spool on a common vertical axis.

BRIEF DESCRIPTION OF THEDRAWINGS 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 simplified diagrammatical view, partly broken away and in section, of apparatus in accordance with this invention; A

FIG. 2 is an end elevational view of the apparatus of FIG. 1;

FIG. 3 is an alternative piston and cylinder arrangement in accordance with this'invention;

FIG. 4 illustrates a rotary shiftingmechanism for alternately connecting the cylinders to inlet and discharge means; and p 1 FIG. 5 shows an arrangement wherebythe discharge line may be shifted to be alternately coupled to each cylinder of the pump.

DETAILED DESCRIPTION OF THE DRAWING Referring to the drawing, and particularly to FIGS. 1 j

portion of the under or bottom side of the base plate 12, which surrounds the bore 16.

A movable rectangular plate 22, smaller than the base plate 12, has bores24, 26 extending therethrough, the spacing between the bores 24, 26 being equal to that between bores 14, 16 or. 16, 18.

Elongated hollow cylinders 28,. 30 extend down in close fit through bores 24, 26, respectively. Each of the cylinders 28, 30 has an open lower end the terminal surfaces of which are flush with the bottom of plate 22 a closed upper end 32, 34, and a floating piston 36 or 38 therein. I

A layer 40 of sealant is disposed betweenthe base plate 12 and the movable plate 22. j

A double acting hydraulic cylinder 42 is coupled to the base plate 12in alignment with the longitudinal axis of the movable plate 22. The piston rod 44 of-the cylinder 42 is attached to the coupling element 46 of the plate 22.

The movable plate 22 is held slidably in contact with the base plate 12 so that the cylinder axes are parallel to and in a common plane with the axes of bores l4, l6,

18 by means of guide members 48, 50 secured to the base plate 12.

A closed hydraulic pump system 52 is coupled to the I 'tops of each cylinder 28, 30 and to the ends of the hydraulic cylinder 42 through a valved controller 54.

The arrangement of FIG. 3 has the cylinders 28a, 30a disposed horizontally with their open ends coupled to bores 24a, 26a through curved end parts 56, 58. In this embodiment, the pistons 36a, 38a are connected by a rod 60 which extends through suitable packing glands 62, 64 in the curved end parts 56, 58.

In the embodiment of FIG. 4, the cylinders 28b and 30b are horizontally disposed, as is the discharge line a.

An intake header 66 has an open end disposed downwardly and an open end facing horizontally against a cylindrical spool 68 whose periphery also seats against the open end portions of each of the cylinders 28b, b and the discharge line 20a. For the purpose of illustration, the spool 68 may be rotated by the friction drive element 70 coupled to a suitable motor 72. In this embodiment, the spool 68 corresponds to the base plate 12 in FIG. 1 and the intake header 66 corresponds to the flange 71 in FIG. 1.

Axially arcuate internal passages 74, 76 extend horizontally through the spool 68, the outlets of the passages being disposed 90 apa rt. The cylinders 28b, 30b are positionally opposed l80 with respect to each other, as are the intake header 66 and discharge line 20a.

FIG. 5 shows in bottom view an embodiment in which a. generally U-shaped tubular conduit 88 is joined at one end 86 to the bottom side of a horizontal plate 22b by a rotatable seal-joint (Chicksan, for example) and communicates through a bore 80 in plate 22b with a discharge line (not shown, but extending above the plate 22b). The open end portions of the cylinders (not shown, but extending above plate 22b) are set in bores 82 and 84, flush with the bottom surface of plate 22b. The other end, 90, of conduit 88 bears against plate 22b in sliding, sealing relationship therewith.

A hydraulic cylinder 92, coupled to the plate 22b, has its actuating rod 94-coupled to the tubular conduit 88 to move the open end 90 of the conduit from being sealed over bore 84 to being sealed over bore 82.

OPERATION Referring to FIGS. 1 and 2, with the controller 54 causing the hydraulic cylinder 42 to have cylinders 28, 30 aligned over bores 16, 18, respectively, hydraulic pressure is applied above the piston 36 and the cylinder 30 is placed under vacuum (by being coupled to the inlet side of the hydraulic pump system). Thus, assuming the plate 12 to be immersed in a slurry, such as mud, for example, as the piston 38 rises as a result of the partial vacuumabove it, slurry will enter the cylinder 30. Simultaneously, hydraulic pressure is urging the piston 36 downwardly toward the discharge line 20. When the piston 38 is at the top of its cylinder, thus loading that cylinder with slurry, and the piston 36 is at the bottom of its stroke, the controller 54 actuates the hydraulic cylinder, advancing the rod 44 to align cylinders 28, 30 over bores 14, 16, respectively. At this time the hydraulic line to each cylinder are reversed (by valving), placing piston 36 under vacuum to draw it upwardly and bringslurry into the cylinder. The piston 38, under pressure, then is forced downwardly, forcing slurry in that loaded cylinder into the discharge line 20 coupled to the plate 12 by the flange 71 around bore 16.

The cycle is repeated at the end of piston movement in the cylinders, with one cylinder filling with slurry while the other cylinder discharges slurry, then moving the position of the cylinders with respect to the discharge line and reversing the piston movement in the cylinders.

Because of the large diameter of the cylinders (several inches are common), debris such as bottles and cans are readily drawn into the cylinders. Preferably the discharge line is at least the same diameter as the diameter of the cylinders in order that debris in the cylinders may be passed on to a spoils area without clogging the discharge line.

It should be noted that the differential barometric pressure at the inlet to the cylinders assists the loadingo the cylinders during that part of the operational cycle.

Referring now to FIG. 3, the plate 22a is moved in the same manner as is the plate 22 in FIGS. 1 and 2. The cylinders 28a, 30a are in horizontally aligned position with respect to each other with their pistons connected by a rod 60 whereby the direct connection between the pistons assists the vacuum in the cylinder which is on the intake cycle.

In the embodiment shown in FIG. 4, the intake header 66 is coupled through passage 74 to cylinder 30b for the intake of slurry. At the same time, cylinder 28b is coupled via passage 76 to the discharge line 20a. At the completion of the cylinders respective intake and discharge cycle, the cylindrical spool 68 is rotated about a vertical axis, aligning cylinder 30b with the discharge line 20a and cylinder 28b with the inlet header 66.

Thus, a 90 turn of the cylindrical spool 68 at the end of each loading-unloading of the respective cylinders aligns each cylinder with the appropriate inlet header or discharge line for the reversal of direction of the respective pistons.

The 90 motion of the cylindrical spool 68 may be either oscillatory with each cycle or a stepped 90 advancement with each cycle.

In the embodiment shown in FIG. 5, the cylinders (not shown) of the pumping apparatus need not be moved to cyclically align them with the discharge line. The rotary joint-seal on the underside of the plate 22b permits the discharge line to be alternately coupled to the bores 82, 84 which communicate with the cylinders. The open end 90 of the tubular conduit 88 makes a sliding seal with the bottom of the plate 22b.

It should be mentioned that, in order to achieve efficient operation of the pumping apparatus, the bores should be spaced at least a full diameter apart.

The hydraulic system, a continuously circulating system utilizing suitable valving in the controller 54, provides both the pressure and vacuum needed to operate the apparatus. The hydraulic fluid may be mainly water with soluble oils as lubricants, or may be an oil.

The controller 54 contains a vacuum switch (not shown) which, when the floating piston seats at the closed end of its cylinder- like member 28 or 30, and the vacuum increases, reverses the hydraulic pressuresuction relationship with the cylinder-like members.

Because no pressure drop occurs across the floating pistons, the slurry and hydraulic fluid do not tend to pass the floating pistons.

In its broadest aspect, the invention is then a slurry pump comprising the combination of: V

1. At least one pair of hollow, cylinder-like members each having a closed end and an open end,

2. a piston disposed within each of the cylinder-like members,

3. means for alternately applying hydraulic pressure between the closed end of one cylinder and the piston therein while applying suction between the closed end of the other cylinder and the piston therein,

4. shiftable coupling means for alternately connecting a discharge line to the open end of each cylinder-like member while pressure is applied at the closed end of that, cylinder, said coupling means comprising a. a body member pierced through by at least one bore and so disposed in sealing and slidable engagement with the open end portions of said cylinders that a condition of alignment between said bore and either open cylinder end can be established or disestablished by a relative sliding motion between said body member and said open cylinder ends,

. b. means for joining the discharge line to the body memberto forma continuous passageway with said line when said bore is aligned with either open cylinder end,

5. means for effecting said, relative sliding motion.

Thus, in the embodiments of FIGS.'1-3, the shiftable coupling means (element (4) of'the preceding combination) is the assembly of base plate 12 (body member (a)) and flange 71 (means for joining the discharge line to the body member). Elements 42, 44, 46, 48, 50 and 22 of FIG. 1 together constitute means (5) above foreffecting a relative sliding motion which in this-case is rectilinear. The open end portions of the cylinders are flush-ste within bores 24 and 26 and bear on the upper surface of plate 12 in sliding, sealing relationship.

In this embodiment, the lower ends of the cylinders per se do notnecessarily have to be mounted flush with the bottom of plate 22. If they are recessed above the lower plate surface, the portions of the plate surface peripheral to the bores 24 and 26 function as the open ends of the cylinders in contact with base plate 12. If the cylinder endsprotrude from the bottom of plate 22, then sliding contact is only between the cylinder ends as such and base plate 12.

In the embodiment of FIG. 4, the shiftable coupling means is the combination of the cylindrical spool 68 ("body member), and the outlet header 20a (means for joining the discharge line Drive means 70 and 72, together with. suitable supporting and bearing means (not shown) constitute means for effecting relative motion In this case, the sliding motion between the open cylinder ends and the body member is rotary, rather than rectilinear.

In the embodiment of FIG. 5, the shiftable coupling means is the combination of tubular conduit 88 (body member pierced through by at least one bore), plate 22b having bore and the rotary seal-joint (the latter. two items constituting means for joining the discharge line to the body member). Elements 92 and 94 of FIG. 5 constitute means for effecting a relative sliding mo tion. In this case, the sliding motion is arcuate and planar.

We claim:

1. Slurry pumping apparatus comprising a plate-like structure having a pair of bores extending therethrough and having mounted thereon a pair of spaced apart hollow, cylinder-like members each having an open end and a closed end and a floating piston, said members being transversely disposed with respect to said platelike structure with their open ends coupled to said bores extending through said plate-like structure, a plate-like base member, said base member being in major surface-to-surface contact with. said plate-like structure, said base member having a discharge bore extending therethrough, means for moving said platelike structure in reciprocating linear mo'tion with respect to said base member whereby each of the bores in said plate-like structure is alternately aligned with said discharge bore, a pair of inlet bores, said inlet bores extending through said base member and-being so disposed with respect to said discharge bore that when one of said bores in said plate-like structure is aligned with said discharge bore, the other bore in said plate-like structure is aligned with one of said inlet bores, means for alternately applying hydraulic pressure between the closed end of one cylinder-like member and the floating piston therein while applying suction between the closed end of the other cylinder-like member and the floating piston therein.

2. Apparatus in accordance with claim 1 wherein said bores in said plate-like structure, said discharge and inlet bores, and the inner periphery of said hollow cylinder-like members have substantially the same transverse cross-sectional configuration.

3. Apparatus in accordance with claim 1 wherein a discharge line is coupled to said discharge bore.

4. Apparatus in accordance with claim 1 wherein controller means are provided for coordinating the movement of said plate-like structure-with respe'ctto said base member with. the application of pressure or vacuum to said cylinder-like members.

5. Apparatus in accordance with claim .1 wherein said cylinder-like members are mounted perpendicularly with respect to said basemember.

6. Apparatus in accordance with claim 1 wherein said means for moving includes a hydraulic cylinder mounted on said base member, said last mentioned hydraulic cylinder having a piston which is coupled to said plate-like structure.

Claims (6)

1. Slurry pumping apparatus comprising a plate-like structure having a pair of bores extending therethrough and having mounted thereon a pair of spaced apart hollow, cylinder-like members each having an open end and a closed end and a floating piston, said members being transversely disposed with respect to said platelike structure with their open ends coupled to said bores extending through said plate-like structure, a plate-like base member, said base member being in major surface-to-surface contact with said plate-like structure, said base member having a discharge bore extending therethrough, means for moving said plate-like structure in reciprocating linear motion with respect to said base member whereby each of the bores in said plate-like structure is alternately aligned with said discharge bore, a pair of inlet bores, said inlet bores extending through said base member and being so disposed with respect to said discharge bore that when one of said bores in said plate-like structure is aligned with said discharge bore, the other bore in said platelike structure is aligned with one of said inlet bores, means for alternately applying hydraulic pressure between the closed end of one cylinder-like member and the floating piston therein while applying suction beTween the closed end of the other cylinderlike member and the floating piston therein.

2. Apparatus in accordance with claim 1 wherein said bores in said plate-like structure, said discharge and inlet bores, and the inner periphery of said hollow cylinder-like members have substantially the same transverse cross-sectional configuration.

3. Apparatus in accordance with claim 1 wherein a discharge line is coupled to said discharge bore.

4. Apparatus in accordance with claim 1 wherein controller means are provided for coordinating the movement of said plate-like structure with respect to said base member with the application of pressure or vacuum to said cylinder-like members.

5. Apparatus in accordance with claim 1 wherein said cylinder-like members are mounted perpendicularly with respect to said base member.

6. Apparatus in accordance with claim 1 wherein said means for moving includes a hydraulic cylinder mounted on said base member, said last mentioned hydraulic cylinder having a piston which is coupled to said plate-like structure.

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