US2285710A - Apparatus for withdrawing liquids from closed containers - Google Patents

Description

F. J. HARLow. 2;2815,710

Filed June 2v, 193e INV EN TOR; FREDERICK J. HARLOW BY M, h ATTO S.

June 9, 1942.

APPARATUS FOR yWI'I'HIRAWING LIQUIDS FROM CLOSED CONTAINERS Patented June 9, 1942 Frederick J. Harlow, Bartlesville, Okla., assigner to Phillips Petroleum Company, a corporation of Delaware Application .lune 27, 1938, Serial No. -216,148

(C1. sz-1)' "I Claim.

This invention relates to apparatus -for unloading liquids from closed vessels andin its more specific aspects, to apparatus for pumping volatile liquids from vessels by means of a pump submerged in the liquid.

Heretofore, considerable difculty has been experienced with conventional types of pumps placed outside the main vessel or container when pumping liqueed petroleum gas, such as butane, propane or' mixtures thereof. The principal trouble has been c iue to the fact that the usual pumping methods and apparatus often resulted yin gas lock due to expansion of the volatile liquids. This gas lock causes pumping to cease and the bearings to become dry and overheated. In addition to objectionable, interruptions in operations, the pumps frequently 'become either par- `tially or completely destroyed. In a pump and driving Amechanism constructed in accordance with the present invention, various types of liquids including liquefied petroleum gas, gasoline, oils, varnishes, paints, and even tar, may be readily and efficiently pumped from closed containers. It will be merely a matter of mechanical skill to alter the design of this equipment in' order to use it eiectively with liquids of differ- ,ent specic gravity, volatility, and viscosity.

The primary object of this invention is to provide apparatus which eliminates all possibility of gas lock in the pump when pumping volatile liquds'out of vessels such 'as tank cars.

Another object of this invention is to equip tank cars for transporting highly volatile liquids with individual pumps'which are adaptable to being actuated by a single source of power at unloading points. In this manner, the cost of the equipment for withdrawing the liquids is materiallyvreduced as onemotor may be used to evacuate a group of cars in succession.

A further object of this invention is to provide apparatus for discharging the liquid contents of a container by means of a pump which is submerged in the liquid. By placing the pump in direct contact with the liquid, greater efllciency of operation vis obtained; and, furthermore, higher pumping capacities may be maintained. Where liquefied petroleumgas is being pumped,

the pressure in the container tends to assist the provide apparatus for discharging liquids from containers, which apparatus is reasonable in rst cost, inexpensive to operate and maintain,

and thoroughly dependable toperform its intended functions. The above and additional objects and advantages will be apparent from the following description and annexed` drawing which respectively describe, and illustrate preferred embodiments of. my invention: and wherein:

Figure 1 is a vertical cross sectional view o 'I portions of a tank car with the apparatus comprising the present invention mountedv thereon. Figure 2is an elevation view of another embodiment of my invention.

Referring to the drawing and more particularly to Figure 1, thereof Reference numerals I0 and Il indicate the upper and lower portions, respectively, of a cony tainer for liquefied petroleum gas, suchvas a' railway tank car.

Generally, containers and tank cars of thistype are provided with coverings of cork or other suitable insulating materiall2 to control the temperature of the contents'thereof. At the top ofthe caris en opening inthe formof a collar I3having an annular flanged ring Il. A closure I5 is removably connected to ring Il by a series of bolts i6. A domeY I1 is supported on closure lIii land. attached thereto by bolts i8.

The dome is provided with a cover I9 which isl pivotally mounted to the dome at 20.

A vertical shaft centrifugal pump is represented b'y pump rotors 2i, drive shaft 22,V and tubular shaft housing 23. While it is apparent that various types of vertical shaft pumps may be employed advantageously for the purposes of this invention, I prefer to use a multi-stage centrifugal pump of the type illustrated. It is observed that the lower portion of the pump extends into a sump 24 in the bottom of the tank car and is braced thereto by straps or brackets 25 which eliminate undesirable vibrations of the pump while the car is in transit or during pumping operations. The shaft housing 23 is connected to closure I5 by a collar 28. A connector 29, concentric with lthe drive shaft and containing suitable frictionless bearings, -is located in closure l5. This connector supports saidv drive shaft and is attached to the closure by a series of stud bolts 30.- A packinggland 3i, also con,- centric with the drive shaft and positioned 'ad-v jacent the connector is used to prevent leakage. 'I'he upper end portion of the drive shaft is splined as indicated at32. l

A plurality of withdrawal-'conduits 33 arein communication with the interior of housing 23, pass through closure I5 and terminate in T-- unions 3l. Each'T-union is provided with an excess flow check valve 35 and a plug 36.v 'In The motive power for actuating the pump is safety should be of an explosion proof type. A chain 4|, connected to the motor by an eye bolt 42 is utilized to mount or remove they motor with respect to the pump. Two legs 43 of a tripod support are shown inthe drawing.l The upperl end of each leg is pivoted to the motor at 44 while the lower portion 45 of each leg is forked to iit over the edge of the dome. Through the agency of set screws 45, the tripod legs 43 are rigidly maintained in position on the car dome. The motor drive shaft 41 is equipped with a universal joint and terminates at its lower extremity in a splined socket 49 which engages splined shaft 32 of the pump.

The practice of this embodiment of my invention contemplates equipping tank cars for the transportation of liquefied petroleum gas with individual pumps. 'I'he pump, including drive shaft 22, housing 23, pump rotors 2|, and discharge conduits 33, is supported by closure |'5 and installed as a unit in the cars. Neither the closure -supplied by a motor 4l. which in the interests of r agendo `/tom of the tank car, the highlyfobjectionablepossibility of gas lock in the pump experienced heretofore is completely eliminated. Pumping continues until the tank is substantially empty, at which time the motor is stopped; valves 35 are closed; the discharge hose is disconnected and plugs 35 are reinserted in the T-unions; stud bolts 46 are loosened; and the motor is raised upwardly and swung away from vthe car. The dome cover is then replaced and we are ready to proceed with the evacuation of another car.'

' of having a separate pump in each container or tank car, I propose to use butone pump and one 'motor at the storageplant or car terminus for the purpose of withdrawing the contents of the nor the pump is removed from the cars except been lled with liqueiied petroleum gas, on reaching their destination, are run to a siding and stopped at an unloading point where the contents of the cars are to be withdrawn. At the unloading spot, a single motor 40 is utilized to successively empty each car. Individual tank car dome covers I3 are first opened and the motor, through the agency of chain 4I and eye bolt 42, is readily swung over the dome by any conventional means such as a crane. The motor is then lowered to operatingl position so that forked ends of legs 43 of the motor tripod t on the edge of the dome and are fastened thereto by set screws 46. At the same time splined socket 43 is placed in engagement with splined portion 32 of pump shaft Plates 38 are now moved away from openings 31 in the car dome and plugs 36 are removed from T-unions 34. Discharge hose is inserted through openings 31 and connected to the T-unions in place of the plugs. With valves 35 set to any desired degree of opening, the motor isplaced inof the car through the discharge hose. It is notedv that the pressure of the vapor in the upper portion of the tank car serves to aid the pump and thereby increases its eillciency and output. Vilince the pump rotors are located in sump 24 in the botcar. The end portion of a tank car is indicated by reference numeral 50. A ilexible conduit 5| is connected to the car by means of a coupling 52. This-conduit also communicates with the interior of chamber or receptacle 53 in which is mounted a pump of the type described above. The liquid is introduced by conduit 5| into chamber 53 where it is transmitted by the pump into discharge conduit 54. Asv in' the case of the first described embodiment of the present invention,

the pump rotors 2| are submerged below the liq-m uid level in the chamber in order' to prevent gas lock. Any vapors that may form inl chamber 53 pass through gas conduit 55, coupling 56, and back to the tank car.

It is to be understood that the form of this invention, herewith shown and described, islto be taken as a preferred example of the same and that various changes in size, shape and arrangement of parts may be resorted to without departing from the spirit of this invention, and further that the theories of operation set out, although believed to be accurate, are not to be considered as the sole basis of the operativeness of this device, but that this device does operate successfully whether or not upon the principles described herein, this invention to be limited only by the appended claim.

I claim: Y

In apparatus for withdrawing a volatile liquid from a closed container, the combination comprising a closed receptacle; a conduit for placing the lower portion of the receptacle in communication with the lower portion of the container; a conduit for placing the upper portion of the receptacle in communication with the upper portion of the container; pumping means in the receptacle, saidpumping means including a pump, a drive shaft operable from the exterior of the receptacle, a housing concentric with the drive shaft, and discharge conduit communicating with the housing and the exterior of the receptacle; and means external the receptacle for operating th pumping means.

FREDERICK J. HARLOW.

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