US2698581A - Compressed gas pump for deep boreholes - Google Patents

Description

2 Sheets-Sheet l E.` MAIER AAMA.

COMPRESSED GAS PUMP FOR DEEP BOREHOLES INVENTOR. Emilio Maier.

ATTORNIY Jan. 4, 1955 Filed sept. 27. 1949 Jan. 4, 1955 E. MAIER coMPREssED @As PUMP PoR DEEP BoREHoLEs 2 Sheets-Sheet 2 Filed Sept. 27

United States Patent O COMPRESSED GAS PUMP FOR DEEP BOREHOLES Emilio Maier, Ramos Mejia, Argentina Application September 27, 1949, Serial No. 118,126

2 Claims. (Cl. 10S-46) The present invention refers to a pump for extracting water or oil from depths exceeding 1,000 metres, or for pressurizing the corresponding liquid, by means of cornpressed gas distributed through an automatic slide valve.

The construction of compressed-gas actuated pumps is already known to the art; in these known constructions, however, the gas is mixed with the liquid and both escape upwardly, reducing their specific weight. This system has the great disadvantage that the liquid cannot ow continuously and that the force of inertia is wasted. The main riser pipe or lifting tube, after each actuating stroke, must be emptied in order to enable the liquid to re-enter the foot valve. This procedure gives rise to long interruptions between one operation and another.

In the system according to the present invention, the compressed gas is allowed to escape freely through one passage or pipe, while the liquid in the main riser pipe or lifting tube continues owing due to the force of inertia during the escape of the gas or the new admission of liquid into the thrust chamber.

Displacement of the slide valve is effected by means of a oat at the bottom of the lifting tube string, balanced against the pressure, or, alternatively, by a piston in the upper units provided with a safety or discharge valve, respectively.

In order that the present invention may be more clearly understood and readily put into practice, a preferred embodiment thereof will now be described with particular reference to attached drawings, said embodiment to be taken as an illustrative example only and in no ways as a limitation of the invention.

In the drawings:

Figures 1-4 inclusive, are vertical sectional views of a deep well pump structure embodying the invention.

In the drawings, the top end of Fig. 2 is a continuation of Fig. l; the top end of Fig. 3 is a continuation of IIig. 2; and the top end of Fig. 4 is a continuation of Like numerals represent like or similar parts throughout the several gures of the drawings.

The outer casing 48 is provided at its upper end with a header 14 having a compressed gas inlet line 4, a lateral liquid outlet connection 13, and another lateral discharge connection 26 for expanded or spent gas.

A lifting tube string 12 is suspended from the header 14 and is supported within and concentrically of the outer casing 48. This lifting tube string includes sections 9 of less diameter than the casing and is composed of a series of pipe sections coupled in the conventional manner and having interposed therein at spaced intervals a series of liquid lifting units. These units intercommunicate in the respect that they all receive compressed gas through pipe 4 and its counterparts 4' and have slide valve controlled ports opened and closed by the movement of either oat valve 6, Figure 4, or a piston 33, Fig. 3 to first admit compressed gas above the water or other liquid trapped in the thrust chamber of each unit and thus cause the pistons to push the liquid upwardly in the lifting tube to outlet connection 13, and, at the end of the liquid lifting stroke permit expanded or spent gases to pass into annular chamber 25 to escape through spent gas discharge connection 26. The annular chamber 25 is, as shown in Figure 1, formed between the outer casing 48 and the tubing string 12. Also as shown in Figure 2. this chamber 25 continues downwardly and is formed between the outer casing 48 2,698,581 Patented Jan. 4, 1955 vice and the tubing 9. In Figure 3, the annular chamber 25 continues to be formed between the outer casing 48 and tubing 9 but as will be observed from the lower end of Figure 3 and the upper portion of Figure 4, the annular space 25 is formed between the tubing 9 and the pipe or sheath 3, the said sheath 3 extending downwardly in Figure 4 and having threaded engagement with the coupling 35.

In the case of the lowermost unit (Fig. 4), the piston 33 is replaced by a valved float 6 so that functionally, though not structurally, the pistons of upper units are the equivalent of the oat since both actuate a related slide valve 16.

In Figure 4, the openings 17 and 18 of this slide valve 16, later to be described, are shown in registry so that compressed gas supplied through line 4 may escape into the gas chamber 5 at the lower end of the lifting tube, said chamber being above the oat 6, and the latter operating in thrust chamber 7 to force liquid out of the lower end of tube section 8 into the lifting space between 8 and 9.

The piston and the slide valve, Figs. 3 and 4 respectively, are shown in position to allow the spent gas to leave the trap chamber, and the piston about to rise due to the rise of the liquid brought about by the filling of the thrust chamber.

The lowermost lifting unit should be submerged from l0 to 30 meters below the level of the liquid which enters through the foot valve 1, and as there is no gas pressure at all the liquid enters and fills the entire interior of the casing 48 including annular space 25 up to the level marked 2, Fig. 3. Pipe 3 surrounding pipe 9 should project a few meters above the liquid level to allow the gas to freely escape without mixing with the liquid. Except for the fact that the lowermost unit uses float 6 instead of piston 33 to actuate the slide valves, a general description of the lowermost unit will apply to those above it and including said pistons.

Compressed gas is caused to pass through pipe 4 into chamber 5 of tube 8 and as thrust chamber 7 is full of liquid the oat 6, in its upper position is subjected to downward pressure to force the liquid in chamber 7 around the lower end of trap tube 8 as shown by the arrows (Fig. 4), to enter the annular passage or space between tube sections 8 and 9, passing through bore 10 to check valves 11 and through the units of tubing string 12 to water or liuuid outlet 13 of header 14.

Each lifting unit has the inner trap tube portion 8 containing a float 6 or a piston 33 which moves downward due to the gas pressure and upward due to the rise of the liquid on account of the filling of the trap chamber of a particular unit or the action of other lower chambers 7. Tube section 9 communicates with passage 10 controlled by check valve 11, mounted in coupling 35. In the uppermost unit of Fig. 3 in addition to the check valve 11, the coupling has a bore for a nipple 28 to connect with the compressed gas pipe 4. The coupling 35 (Fig. 4) has at its lower end a reduced threaded portion 39 to carry tube section 8 and is provided with a central bore 36, a bore 10 for the passage of the liquid, and also has a bore 24 for the compressed gas and a bore 23 for the exit of the spent gas.

The upper socket end of central bore 36 is threaded at 30 to receive a pipe 21 having ports 22 communicating with spent gas bore 23 leading to exhaust suace 25. The upper end of an exhaust pipe 21 rigidly receives the pressure gas pipe section 4' which communicates with bore 24 leading to main gas pressure line 4. The pipe 21 flares outwardly about the pipe section 4 and then iits the same snugly at its lower end, said ared portion providing a space or passage for conducting spent gas to ports 22 from ports 20 when ports 19 of slide valve member 16 (Fig. 4) register therewith. The gas pressure pipe section 4 is also provided with ports 18 adapted to register with ports 17 to permit fresh gas pressure to enter chamber 5 when slide valve 16 is pushed up to close ports 19 and 20. The upper end 16a of slide valve 16 is of reduced diameter to enter a socket portion 35 in the coupling 35, said reduced portion acting as a guide and the shoulder between the reduced portion and the main portion constituting an abutment to limit the sliding movement of the valve 16.

As shown in Figs. 2 and 4 the slide valve is externally provided with annular keeper grooves 27 and 27 to receive rollers 37 carried by spring arms 38 rigidly supported at their upper ends on the lower portion of coupling 35. This arrangement, in different positions of the slide valve keeps ports 19 and 20, or ports 17 and 18 in registry for the proper phase of the pumping cycle. Said slide valve member has an elongated stem portion 46 embracing gas pipe extension 4' and at the junction ofsaid sleeve portion with the valve body, there is provided a piston abutment shoulder 47.

The piston 33 (Fig. 3) lits snugly in tube section 8 and includes a bushing 34 which slidably bears on the lower stem portion 46 of the valve member 16 (Fig. 2) which telescopes over the lower end of gas pipe extension 4.

When the slide valve is in its upper position, ports 17 and 18 register (see Figs. 2 and 4) and allow the compressed gas to enter chamber 5 pressing the piston downward along extension 46 of.slide valve 16 until it strikesagainst abutment 15 of the slide valve displacing the latter to its lower position, blocking the inflow of compressed gas until ports 19 of the slide valve and 20 of the pipe 21 to register, allowing the spent gas to escape or exhaust through the openings 22 of passage 23 and space 25 and outlet 26 of header 14. The piston after the exhaust cycle, slides upward again under liquid pressure until it strikes shoulder 47 of the slide valve and again allows compressed gas to enter through ports 17 and 18.

When the rollers 37 enter an annular groove 27 of the slide valve the latter is in its upper position, and is held there until either oat 6 or piston 33 on descending strikes against abutment 15 of the slide valve sleeve, displacing it downward until ports 17 are closed and ports 19 of the valve and ports 20 of the pipe 21 register. In this position, rollers 37 enter the annular groove 27', and the gas escapes from chamber 5 through registering ports 19 and 20 and into space between 4 and 21 and goes out through ports 22 into spent gas passage 23 to the annular space 25 between outer casing 48 and lifting ttbe section 9 to expanded gas outlet 26 of header 14. The piston then begins to slide upward, due to the force of rising liquid, reaching shoulder 47 of the valve, displacing same until ports 19 and 20 become closed and ports 17 and 18, (Figs. 2 and 4) regis ter again to again allow the compressed gas from pipe 4 to enter chamber 5. In this case, the rollers enter the annular groove 27 of the slide valve holding the same until the piston again reaches top 15 of the slide valve, repeating the operation.

In order to prevent the compressed gas pipe 4 from being crushed at its lower end by its own weight (for this would amount, anyway, to about 60 kg. per 100 meters, respectively, to 600 kg. per 1,000 meters) a special device is provided permitting the pipe 4 to be suspended and straightened in the lifting tube 9 at intervals of 50 meters each. This device consists of a special nipple 41 provided with threads 42 whereon coupling 43 is threaded to permit pipe 4 to be supported, and to rest on seat of a spider 44 mounted on ring 45 projecting inwardly from the joint of the lifting tube 9.

The invention as described and illustrated may be clearly understood and no further explanations will be required by those versed in the matter.

As the invention herein shown and specied has been described in the manner of a preferred embodiment which is to be considered as an illustrative example and in no ways as a limitation upon the invention, same may be subjected to changes in its construction and details, without thereby departing from its essential nature, as clearly dened in the following claims.

I claim:

1. A pump for the extraction of liquids from casings of great depth including, a header having a uid outlet, a spent gas outlet and a gas pressure pipe inlet, a gas pressure pipe connected to said inlet a liquid lifting tube string suspended by the header in the casing, said string including concentric spaced liquid and spent gas tubing sections respectively for carrying separately tiuid upwardly to said uid outlet and spent gas to said spent gas outlet of the header, a plurality of intercommunicating lifting units, each unit comprising, a coupling having adjacent ends of the lifting tube and spent gas tube sections attached thereto, said coupling having a central bore communicating with said gas pressure pipe, and also having a liquid bore in valved communication with a related liquid tubing section and a spent gas bore in communication with the venting space between the liquid and spent gas tubing sections, a trap tube forming a thrust chamber and depending from the coupling and of less diameter than the related liquid tube section to alford communication to said liquid bore, a gas pressure tube extension fitted at its upper end in the central bore and communicating with the inlet of the gas pressure pipe, said extension having lateral gas pressure outlet ports and closed at its lower end, an exhaust pipe surrounding a portion of the said extension in spaced relation thereto and fitting the same tight at its upper and lower end portions, said exhaust pipe having upper outlet ports communicating with the spent gas bore of the coupling and also having lower spent gas inlet ports, a sliding valve member shiftable on the said extension and having a lower stem portion and an enlarged upper valve portion provided with upper ports for registry with the lower spent gas ports of the exhaust pipe and lower gas pressure ports for establishing communication with the gas pressure ports of said pressure gas tube extension, abutment means on the upper and lo wer portions of the valve member, and piston means slidable on the stern port1on of the valve member and fitting in said trap tube, said piston being responsive to gas pressure from above and liquid pressure from below in the trap tube to alternately engage said abutment means to shift the upper valve portion to regulate the registry of the said gas pressure ports and the said spent gas ports.

2. An apparatus according to claim l, wherein the upper portion of the sliding Valve member is provided with spaced keeper grooves, and spring urged rollers carried by the coupling enter said grooves to maintain the said gas ports of the extension and valve member and also the spent gas ports of the valve member and exhaust pipe in registry on the pressure and exhaust strokes of the piston operated valve member.

References Cited in the le of this patent UNITED STATES PATENTS

Images