US3431744A - Pump for liquefied gases - Google Patents
Pump for liquefied gases Download PDFInfo
- Publication number
- US3431744A US3431744A US584139A US3431744DA US3431744A US 3431744 A US3431744 A US 3431744A US 584139 A US584139 A US 584139A US 3431744D A US3431744D A US 3431744DA US 3431744 A US3431744 A US 3431744A
- Authority
- US
- United States
- Prior art keywords
- pump
- chamber
- liquid
- liquefied gas
- container
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
- F04B53/10—Valves; Arrangement of valves
- F04B53/12—Valves; Arrangement of valves arranged in or on pistons
- F04B53/125—Reciprocating valves
- F04B53/126—Ball valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B15/00—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts
- F04B15/06—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts for liquids near their boiling point, e.g. under subnormal pressure
- F04B15/08—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts for liquids near their boiling point, e.g. under subnormal pressure the liquids having low boiling points
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B23/00—Pumping installations or systems
- F04B23/02—Pumping installations or systems having reservoirs
- F04B23/021—Pumping installations or systems having reservoirs the pump being immersed in the reservoir
- F04B23/023—Pumping installations or systems having reservoirs the pump being immersed in the reservoir only the pump-part being immersed, the driving-part being outside the reservoir
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
- F04B53/08—Cooling; Heating; Preventing freezing
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
- F04B53/16—Casings; Cylinders; Cylinder liners or heads; Fluid connections
- F04B53/162—Adaptations of cylinders
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
- F04B53/00—Component parts, details or accessories not provided for in, or of interest apart from, groups F04B1/00 - F04B23/00 or F04B39/00 - F04B47/00
- F04B53/16—Casings; Cylinders; Cylinder liners or heads; Fluid connections
- F04B53/162—Adaptations of cylinders
- F04B53/164—Stoffing boxes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
- F17C2223/00—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel
- F17C2223/01—Handled fluid before transfer, i.e. state of fluid when stored in the vessel or before transfer from the vessel characterised by the phase
- F17C2223/0146—Two-phase
- F17C2223/0153—Liquefied gas, e.g. LPG, GPL
- F17C2223/0161—Liquefied gas, e.g. LPG, GPL cryogenic, e.g. LNG, GNL, PLNG
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17C—VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES
- F17C2227/00—Transfer of fluids, i.e. method or means for transferring the fluid; Heat exchange with the fluid
- F17C2227/01—Propulsion of the fluid
- F17C2227/0128—Propulsion of the fluid with pumps or compressors
- F17C2227/0171—Arrangement
- F17C2227/0178—Arrangement in the vessel
Definitions
- liquefied gases are used on a large scale in industry, more particularly in the vacuum technique, for example for collecting, i.e. condensing, vapours of unwanted substances or, in a more ygeneral sense, of gases having a condensation temperature which is higher than that of the boiling point of the liquefied gas used as a coolant.
- the liquid being pumped may partly evaporate due to the heat produced by friction between the piston and the cylinder, the heat supplied by conduction by the pump itself from its parts which contact the surroundings, and the heat which may be produced by compression of the liquid as it is flowing through the channels, The resulting gases interfere with satisfactory operation of the pump.
- the pump for liquefied gases according to the invention h-as been designed for the direct feeding of a device with a cooling agent circulaing in it for collecting vapours or other devices intended to obtain or maintain very low temperatures from bottles containing liquefied gas which are sold commercially.
- the pump and its method of circulating liquefied gas according to the invention is distinguished from known pumps by a plurality of features which considerably limit the losses of liquid.
- the pump for liquefied gas which gas is contained in a vessel, comprises a piston which is connected to a reciprocatable piston rod and which is housed with very small clearance in a pump body or housing which may be immersed in rthe liquefied gas and in which a valve system permits the g-as to be supplied into the pump body and pressed out of it and, according to the invention, it is characterized in that the pump includes two chambers which co-axially surround each other and the said piston rod, the first of which chamber communicates a one end with the pump body and at its other end with -an outlet which may be connected to a circulation system for the liquefied gas present outside the pump, and the second of which has, at one end, at least one aperture through which it communicates with the-said vessel and has, at its oher end, an inlet which may likewise be connected to the circulation system present outside the pump and also an outlet which is situated above the inlet and empties into the atmosphere.
- the liquid fiows through the first chamber which is cooled by liquid flowing back from said system into the second chamber. This prevents the liquid present in the first chamber from being evaporated as the result of heat of conduction coming from without.
- This double-chamber construction also reduces the conduction of heat to the liquid in the container.
- the pump according to the invention has two seals which bound a chamber in which the vapours of the liquid being pumped may be partly collected and heated so that in this chamber a certain pressure above atmospheric pressure arises which reduces the loss of vapour leaking to the exterior.
- the liquid being pumped evaporates in part as it flows through the circulation system present outside the pump and as it cools the walls contacted by it. After having flowed through the system, the liquid and the vapour are collected again.
- the liquid portion returns to the container Ifilled with liquefied gas through the second of the above-mentioned double chamber.
- the evaporate-d portion is led through the second outlet, which is situated at a suitable height, into a closed insulated chamber which surrounds the greater part of the section of the pump present outside the container with liquid.
- the cold vapour cools this section of the pump, thus reducing the temperature gradient between the parts of the pump located inside and outside the container and hence also reducing the losses due to heat of conduction to the interior.
- Such a construction also affords the advantage that this cold gas which has been produced by evaporation is very dry, resulting in cooling being obtained without the formation of ice on this part of the pump.
- the metal used for the structure of the pump naturally has a thickness which is as small as possible in order to inhibit thermal conduction, but this thickness must vary with the mechanical forces occurring in the various sections.
- the metal must be strictly neutral relative to the 3 liquids being pumped.
- a pump according to the invention may function without any lubrication of the parts contacting the liquid gas so that it is possible to use any arbitrary gas.
- FIGURE 1 shows a longitudinal section of a pump for liquefied gas which is partly immersed in liquefied gas present in an insulated container.
- FIGURE 2 is a sectional view -on a larger scale of a section of the pump of FIGURE l.
- FIGURE 3 is also a sectional view on a larger scale of the double chamber for the leaving and returning liquids and illustrates the manner in which the various tubular Iparts forming the pump are connected together.
- the pump in the figures is subdivided into five sections indicated by I, II, III, IV and V.
- FIGURE 1 shows that the pump having a housing of which the lower end is partly immersed in liquefied gas contained in an ordinary insulated bottle or container 2.
- the lower part of the pump which is present in the liquefied gas comprises a piston 3 connected to a piston rod 18 and formed by the body of a ball type valve 3a having ducts 3b.
- the piston 3 is adapted to reciprocate in a cylinder 4 having a length which corresponds to the stroke of piston 3.
- the cylinder 4 is bounded at the bottom by another ball type valve 5 which is fixed in the cylinder by contraction.
- Section II A stainless steel tube 6 of a comparatively small wall thickness, which constitutes the outer envelope of the pump, is fixed on cylinder 4 by contraction.
- the further component parts of the pump are mounted in tube 6, the separations between the various sections of the pump being obtained by separating rings provided at different levels.
- the tube 6 is fixed by contraction on the outer surface of a ring 7 placed in the pump body at a height such that it projects above the level of the liquefied gas when the bottle 2 is completely filled.
- the contracted connection is obtained, for example, by driving the metal of tube 6 by means of a pressure roller M into a re-entrant part 7a of the ring 7 (see FIGURE 3).
- the ring 7 has a thinner part 8 (see the detail in FIG- URE 3) on which a tube 9 likewise of a comparatively small wall thickness is fixed by contraction, the tube 9 being secured at its upper end, likewise by contraction, on a thinner part 10 of a ring 11 which is identical with the ring 7.
- the outer chamber which lies between the tubes 6 and 9 has near the ring 11, an inlet 12 which is soldered on the tube 6 and which may be connected to a circulation system (not shown) located outside the pump.
- the tube 6 in section III is provided with holes one of which, indicated by 13, is provided in the upper part above the inlet 12 and on which an outlet is soldered, whereas the other holes 14 and 15 are provided in the lower part.
- Section IV The tube 6 which is secured, on the one hand, to the ring 11 and on the other to a ring 16 which constitutes a bearing and is provided with a stuffing box for the sealing round about the piston rod 18 forms another chamber on which an outlet 17 is soldered which is intended to be connected to the circulation system present outside the pump.
- Section V This section comprises a chamber which is formed by the tube 6 around the piston rod 18 and which is closed at the top by a sealing bearing 19.
- the piston rod 18 which transmits a reciprocating movement to the piston 3 is driven by an electric motor with transmission shown diagrammatically at 20.
- the portion of the pump which is located outside the container 2 is insulated by a space 21 filled with heatinsulating material.
- a space 21 filled with heatinsulating material For example, a polyamide is used for the walls of space 21 and a sponge polystyrene as the filling.
- the lower surface of space 21, which forms the supporting surface of the pump on the neck of the container, comprises an insulating ring 22 of which the edges contacting the tube 6 are bevelled as shown at 23 so that the heat-exchange between the tube 6 and the ring 22 remains limited.
- the pump operates in the following manner: after having passed the complex of valves 3 and 5, the liquid in section II rises in the chamber bounded by tube 6 and piston rod 18 and in section III in the chamber bounded by tube 9 and piston rod 18. The liquid then leaves the pump through the outlet tube 17 after having passed the ring 11. Subsequently the liquid and gaseous media return through the inlet tube 12 to the pump from the circulation system present outside the pump. The liquid medium passes the chamber located between the tubes 6 and 9 in section III to be collected through the apertures 14 and 15 in the container 2. The cold gaseous medium escapes through the outlet 13 and fiows through the space 21 from which it escapes into the atmosphere.
- Section IV of the pump contains fluid medium and a little gaseous medium which has been produced, for example, due to internal frictions. It is impossible to prevent said gaseous medium from penetrating the chamber of section V through the bearing 16. Part of this chamber contacts with the surroundings. If the bearing 19 seals said chamber sufficiently, a pressure slightly above atmospheric pressure will be built up in it due to the heating 0f the gaseous medium, resulting in renewed flowing in of said gaseous medium being inhibited to a considerable extent, so that the latter escapes through the outlet 17.
- Neoprene provides a better seal than polytetrafiuoroethylene, but in the conditions here obtained the presence of the superpressure chamber weakens the imperfectnesses of the latter.
- a pump apparatus for circulating a fluid such as liquefied gas between a container and a system outside the container, the pump when upright including a housing which has a lower end immersible into the fluid in the container and defines by its inner walls a passage for said iiuid and for a piston driven reciprocally by a piston rod, the improvement in combination therewith comprising a sleeve mounted within the housing between the passage walls and the piston rod, thereby defining an outer chamber between said walls and the sleeve and an inner chamber between said sleeve and the rod, the outer chamber having an inlet and an outlet respectively in communication with said system and with the containers interior, the
- inner chamber having an inlet and an outlet respectively in communication with the housings lower end for receivi ing liquefied gas therethrough from the container and with said system, the outer chamber having a supplementary outlet through which vapor of said liquefied gas in said outer chamber is fiowable to the atmosphere, the inner and outer chambers prevented from direct intercommunication.
- the housing further comprises a third chamber through which the piston rod moves, this third chamber having one end defining a seal separating the third and inner chambers and a remote end separating the third chamber from the atmosphere.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Reciprocating Pumps (AREA)
- Filling Or Discharging Of Gas Storage Vessels (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR34515A FR1464689A (fr) | 1965-10-11 | 1965-10-11 | Perfectionnements aux pompes pour gaz liquéfiés |
Publications (1)
Publication Number | Publication Date |
---|---|
US3431744A true US3431744A (en) | 1969-03-11 |
Family
ID=8590184
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US584139A Expired - Lifetime US3431744A (en) | 1965-10-11 | 1966-10-04 | Pump for liquefied gases |
Country Status (5)
Country | Link |
---|---|
US (1) | US3431744A (xx) |
DE (1) | DE1653578A1 (xx) |
FR (1) | FR1464689A (xx) |
GB (1) | GB1160564A (xx) |
NL (1) | NL6614014A (xx) |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3510102A (en) * | 1968-08-08 | 1970-05-05 | Atomic Energy Commission | Valve assembly |
US3689206A (en) * | 1970-11-02 | 1972-09-05 | Dresser Ind | Oil well pump with permanent connections and a plunger therefor |
US4156584A (en) * | 1976-07-19 | 1979-05-29 | Carpenter Technology Corporation | Liquid cryogen pump |
US4418544A (en) * | 1981-07-03 | 1983-12-06 | Kernforschungsanlage Julich Gmbh | Pump for very cold liquids |
WO1984002969A1 (en) * | 1983-01-28 | 1984-08-02 | Eugene B Zwick | Cryogenic storage tank with built-in pump |
US4860545A (en) * | 1988-11-07 | 1989-08-29 | Zwick Energy Research Organization, Inc. | Cryogenic storage tank with a retrofitted in-tank cryogenic pump |
US4956975A (en) * | 1989-08-17 | 1990-09-18 | Gustafson Keith W | Shutoff valve for cryogenic liquid storage tank |
US5545015A (en) * | 1993-06-11 | 1996-08-13 | Societe Europeene De Propulsion | Self-cooled and removable integrated cryogenic liquid pump |
WO2006133813A1 (de) * | 2005-06-17 | 2006-12-21 | Linde Aktiengesellschaft | Kryoverdichter mit hochdruckphasentrenner |
CN101476555B (zh) * | 2009-01-15 | 2011-07-06 | 联塑(杭州)机械有限公司 | 沉氮式泵头 |
US20170037836A1 (en) * | 2015-08-06 | 2017-02-09 | Caterpillar Inc. | Cryogenic Pump for Liquefied Natural Gas |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2018144A (en) * | 1933-04-29 | 1935-10-22 | Linde Air Prod Co | Method and apparatus for transferring gas material |
US2439957A (en) * | 1943-10-21 | 1948-04-20 | Air Prod Inc | Pump for liquefied gases |
US2837898A (en) * | 1953-07-15 | 1958-06-10 | Union Carbide Corp | Differential plunger type liquefied gas pump |
US2855859A (en) * | 1955-09-20 | 1958-10-14 | Messer Adolf Gmbh | Liquid-oxygen pumps |
US3145629A (en) * | 1960-12-13 | 1964-08-25 | Union Carbide Corp | Cryogenic pump sealing rings |
US3181473A (en) * | 1961-06-19 | 1965-05-04 | Air Reduction | High-pressure, cavitation free piston pumps |
US3220202A (en) * | 1964-05-15 | 1965-11-30 | Union Carbide Corp | Apparatus for storing and pumping a volatile liquid |
US3299828A (en) * | 1964-12-16 | 1967-01-24 | Lox Equip | Reciprocating cryogenic pump |
-
1965
- 1965-10-11 FR FR34515A patent/FR1464689A/fr not_active Expired
-
1966
- 1966-10-04 US US584139A patent/US3431744A/en not_active Expired - Lifetime
- 1966-10-05 NL NL6614014A patent/NL6614014A/xx unknown
- 1966-10-07 GB GB44936/66A patent/GB1160564A/en not_active Expired
- 1966-10-07 DE DE19661653578 patent/DE1653578A1/de active Pending
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2018144A (en) * | 1933-04-29 | 1935-10-22 | Linde Air Prod Co | Method and apparatus for transferring gas material |
US2439957A (en) * | 1943-10-21 | 1948-04-20 | Air Prod Inc | Pump for liquefied gases |
US2837898A (en) * | 1953-07-15 | 1958-06-10 | Union Carbide Corp | Differential plunger type liquefied gas pump |
US2855859A (en) * | 1955-09-20 | 1958-10-14 | Messer Adolf Gmbh | Liquid-oxygen pumps |
US3145629A (en) * | 1960-12-13 | 1964-08-25 | Union Carbide Corp | Cryogenic pump sealing rings |
US3181473A (en) * | 1961-06-19 | 1965-05-04 | Air Reduction | High-pressure, cavitation free piston pumps |
US3220202A (en) * | 1964-05-15 | 1965-11-30 | Union Carbide Corp | Apparatus for storing and pumping a volatile liquid |
US3299828A (en) * | 1964-12-16 | 1967-01-24 | Lox Equip | Reciprocating cryogenic pump |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3510102A (en) * | 1968-08-08 | 1970-05-05 | Atomic Energy Commission | Valve assembly |
US3689206A (en) * | 1970-11-02 | 1972-09-05 | Dresser Ind | Oil well pump with permanent connections and a plunger therefor |
US4156584A (en) * | 1976-07-19 | 1979-05-29 | Carpenter Technology Corporation | Liquid cryogen pump |
US4418544A (en) * | 1981-07-03 | 1983-12-06 | Kernforschungsanlage Julich Gmbh | Pump for very cold liquids |
WO1984002969A1 (en) * | 1983-01-28 | 1984-08-02 | Eugene B Zwick | Cryogenic storage tank with built-in pump |
US4472946A (en) * | 1983-01-28 | 1984-09-25 | Zwick Eugene B | Cryogenic storage tank with built-in pump |
US4860545A (en) * | 1988-11-07 | 1989-08-29 | Zwick Energy Research Organization, Inc. | Cryogenic storage tank with a retrofitted in-tank cryogenic pump |
US4956975A (en) * | 1989-08-17 | 1990-09-18 | Gustafson Keith W | Shutoff valve for cryogenic liquid storage tank |
US5545015A (en) * | 1993-06-11 | 1996-08-13 | Societe Europeene De Propulsion | Self-cooled and removable integrated cryogenic liquid pump |
WO2006133813A1 (de) * | 2005-06-17 | 2006-12-21 | Linde Aktiengesellschaft | Kryoverdichter mit hochdruckphasentrenner |
US20080213110A1 (en) * | 2005-06-17 | 2008-09-04 | Linde Aktiengesellschaft | Apparatus and Method for Compressing a Cryogenic Media |
CN101476555B (zh) * | 2009-01-15 | 2011-07-06 | 联塑(杭州)机械有限公司 | 沉氮式泵头 |
US20170037836A1 (en) * | 2015-08-06 | 2017-02-09 | Caterpillar Inc. | Cryogenic Pump for Liquefied Natural Gas |
US10024311B2 (en) * | 2015-08-06 | 2018-07-17 | Caterpillar Inc. | Cryogenic pump for liquefied natural gas |
Also Published As
Publication number | Publication date |
---|---|
GB1160564A (en) | 1969-08-06 |
DE1653578A1 (de) | 1971-04-29 |
FR1464689A (fr) | 1967-01-06 |
NL6614014A (xx) | 1967-04-12 |
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