Fuel transferring system and method of use

A portable system for transferring liquids, such as diesel fuel, from a first tank, such as a railcar, to a second tank, such as on a transport truck. The system is self-contained and comprises a pump driven by an engine fueled by the liquid being transferred. A meter measures the amount of liquid being transferred. An inlet hose is used to connect the system to the railcar, and an outlet hose is used to connect the system to the transport truck. Air from the truck may be used to blow any liquid out of the outlet hose after a transferring operation.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to equipment for unloading petroleum products such as diesel fuel from one storage or transport tank to another, such as from a railcar to a transport trailer, and more particularly, to a portable system for unloading a railcar into a transport trailer without the necessity of any permanently installed equipment and which can be used at virtually any site at which access to the railcar is available.

2. Brief Description of the Prior Art

The use of railroad tank cars for bulk transportation of petroleum products, such as diesel and other fuels, is well known. It is also known to transport such fluids over the highways by truck using specially designed transport trailers, often called tanker trailers.

The railcars have top openings therein through which the railcars can be filled or loaded and bottom openings through which they can be emptied or unloaded. A valve on the bottom opening is used to open and close it. Normally, loading the railcar is done at a refinery site. When the railcars travel to an unloading terminal, permanent equipment is used to unload the railcar and transfer the product therein to another vessel of some sort. This might be a stationary storage tank, but often is a transport trailer. Both the stationary tanks and the tanks on the transport trailers also have openings therein with valves controlling them through which these vessels can be loaded and subsequently unloaded. It is not uncommon for these tanks to have separate compartments for different products, for example, diesel fuel and gasoline. Separate openings and valves are used for the different compartments.

When transferring a liquid such as diesel fuel, the previously mentioned permanent system is used. Such a permanent system includes a pump, usually driven by an explosion-proof electric motor and a meter downstream of the pump to measure and frequently record the amount of fuel transferred. An inlet hose is connected between inlet piping to the pump and the valve on the railcar, and an outlet hose is connected between outlet piping from the meter and the desired valve on the transport trailer. These hoses may have grounding wires woven therein so that when they are connected to metal piping, valves, etc., the chance of static electricity is minimized. This is necessary because a small spark could ignite the products being transferred or at least vapors therefrom.

In these prior art permanent installations, obviously it is necessary to take the transport trailer to the terminal to which the railcars have been brought. The unloading of the product from the railcar cannot take place anywhere else. Therefore, if it is desired to unload the railcar at any other site, the permanent system is unusable. Thus, there is a need for a system which can be used to transfer product from a railcar when it is parked at a site which does not have an unloading terminal located there. The present invention solves this problem by providing a portable transferring and unloading system mounted in a small trailer which can be taken to virtually any site at which a transport trailer can be located near the railcar.

In permanent installations, although some lengths of hoses are used, most of the piping is fixed, and it does not matter if fluids remain therein after a transferring or pumping cycle. Any spillage is caught in permanent areas around the system. In the portable system of the present invention there is a relatively small amount of fixed piping in the trailer, and most of the connections between the railcar and the transport trailer are with flexible hoses. When the pumping is done, the outlet hose will still be full of fluid. After disconnecting such a hose, the hose would be extremely heavy and difficult to handle and there would be spillage of some, if not most, of the liquid in the hose. This not only would waste valuable product, such as diesel fuel, but such spills would be detrimental to the environment and most likely would violate environmental laws or regulations. The present invention solves this problem by providing a connection in the outlet of the system whereby pressurized air from the truck is used to blow the remaining liquid out of the outlet hose and into the transport trailer.

In today's petroleum market, prices can fluctuate significantly depending on economic and world conditions and events. Marketers of petroleum products, such as diesel fuel, want to find the fuel at the least possible price in order to have a competitive advantage, or at least to be competitive with other marketers. Often, a lower price might be found at some distance away from the marketer's normal supply point. In such cases, marketers may take their transport trucks to those more remote locations to load with petroleum products if the cost of transportation is not prohibitive. This still requires the transport truck to be taken to a terminal where railcars are being unloaded, and this may add more cost than can be absorbed by the marketer. Also, even once at the terminal, it may take some time for a particular transport truck to be filled if a number are waiting. If unloading could be speeded up, this would be an advantage for everyone. Further, sometimes the railcars are still at a siding somewhere and not yet located at a terminal, and currently, this means they cannot be unloaded until they are moved to a terminal. This may result in a time delay which increases the cost of transportation for the suppliers who move the products by rail. If railcars could be unloaded earlier, the supplier would get paid sooner, and the railcar could be turned around more quickly to be reloaded. Also, if unloading could be accomplished more quickly, marketers might be able to buy it at a lower price and get the petroleum into the marketing stream earlier. All of this would improve cash flow at all levels of the petroleum market, from the supplier to retail consumers.

The present invention provides such an economic improvement because it can be used by the marketer to unload railcars and load transport trucks more quickly at terminals and even do this where there is no terminal because the inventive system is portable and self-contained.

SUMMARY OF THE INVENTION

The present invention includes a portable system for unloading fluids such as diesel fuel from one tank to another such as from railcars to transport trailers of the type pulled by trucks. The entire system is self-contained, and no permanent equipment at the unloading site is necessary. Thus, the transfer can take place at any location where the transport trailer can be positioned near the railcar, and it is not necessary to move the railcar to a specific unloading terminal.

The invention may be described as a portable system for transferring a liquid from a first tank such as a railcar to second tank such as a transport trailer in which the system comprises a trailer adapted for connection to a vehicle, a pump mounted on the trailer and having an inlet and an outlet, an engine mounted on the trailer and adapted for driving the pump, a flow meter mounted on the trailer and having an inlet in communication with the outlet of the pump and an outlet, an inlet hose storable in the trailer and connectable between the railcar and the inlet of the pump, and an outlet hose storable in the trailer and connectable between the outlet of the meter and the tank. The connection between the pump and meter is such that liquid pumped by the pump flows through, and is measured by, the meter.

The engine runs on the same liquid as that being transferred. Preferably, the engine is a diesel engine, and the liquid is diesel fuel. Some of the fuel is used to fill the fuel tank of the engine so that a separate fuel supply is unnecessary.

The system may further comprise an air line in communication with the outlet of the meter and an air hose connectable between the air line and an air source, whereby liquid in the outlet hose may be forced by air pressure into the tank.

In the preferred embodiment, the tank is a portion of a transport trailer on a transport truck, and the air source is mounted on the truck.

The hoses are preferably grounding hoses with a grounding wire woven therein.

The system may further comprise an alarm connected to the second tank for providing an audible signal indicating a predetermined liquid level, such as the maximum desired level, in the second tank.

The present invention also may be described as including a method of obtaining fuel at an optimum price comprising the steps of (a) locating a source of supply of the fuel at an acceptable price and contained in a railcar at a location accessible by a motor vehicle, (b) moving a portable liquid transferring system to the location, (c) moving a transport truck to the location, (d) connecting the system to the railcar and transport truck, (e) activating the system to pump the fuel from the railcar to the transport truck, (f) disconnecting the system from the railcar and transport truck, and (g) moving the transport truck to the desired marketing point. Step (d) preferably comprises connecting an inlet hose between the railcar and the system and connecting an outlet hose between the system and the transport trailer.

Between steps (e) and (f) the method may further comprise blowing liquid out of the outlet hose by applying air pressure thereto. The air may be supplied by an air system on the transport truck.

Step (e) preferably comprises driving a pump with an engine for pumping the fuel from the railcar to the transport truck. The method may further comprise fueling the engine with a portion of the fuel being transferred.

Step (e) may comprise sounding an audible alarm when the fuel in the transport truck reaches a predetermined level.

Numerous objects and advantages of the invention will become apparent as the following detailed description of the preferred embodiment is read in conjunction with the drawings illustrating such embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, and more particularly toFIG. 1, the diesel fuel transferring system of the present invention is shown and generally designated by the numeral10. System10is shown positioned on a ground surface12adjacent to railroad tracks14.FIG. 1is for illustration purposes only, and it is not intended to convey the impression that tracks14are at a higher elevation than ground surface12. No specific relative height is necessary for system10to be used.

A railroad tank car16, also referred to simply as railcar16, is positioned on tracks14. Of course, more than one railcar16may be present at any time. Railcar16is of a kind known in the art and has a tank18mounted on rail trucks20. At the bottom of tank18is a railcar valve22through which the liquid in the tank may be emptied or unloaded.

Positioned adjacent to system10on ground surface12is a transport truck24of a kind known in the art. Transport truck24has a tractor26connected to a transport trailer28by a fifth wheel30. Transport trailer28includes a tank32mounted on rear wheels34. Tank32has a transport valve36on the bottom thereof through which the tank may be filled or loaded with liquid or through which the tank may be emptied or unloaded. Although tank32is illustrated for simplicity as having a single transport valve36thereon, transport trailer tanks typically have multiple liquid compartments therein with a separate transport valve for each.

System10comprises, among other things, a pump38and a flow meter40. The inlet of meter40and the outlet of pump38are connected to one another as will be further described herein. During operation of system10, railcar valve22is connected to the inlet of pump38with an inlet hose42, and the outlet of meter40is connected to transport valve36by an outlet hose44.

Referring now toFIGS. 2–4, more details of system10will be discussed. System10also comprises a trailer46in which all of the other components are mounted. Trailer46is of generally conventional construction including a frame48mounted on an axle50and supported on wheels52. A tongue54extends from frame48and has a hitch56for attachment to a vehicle (not shown) adapted for pulling trailer46. Trailer46also has side walls58and a front wall60extending upwardly from frame48with a top62covering the trailer. Rear doors64are hingedly attached to side walls58. A floor66extends across frame48.

Pump38is installed on a pump base68mounted on floor66. Also mounted on pump base68is a diesel engine70which drives pump38through a coupling72.

Pump38is illustrated as a centrifugal pump having a center inlet74and an outlet76. One preferred pump38is a Gorman-Rupp 3X3 with 10 horsepower diesel engine Model No. 83A1-L100EE-X. However, other types of pumps could be used, and the invention is not intended to be limited to a centrifugal pump or any particular pump design or manufacturer.

An inlet line78is connected to pump inlet74. An inlet valve80is disposed in inlet line78. Preferably, but not by way of limitation, inlet valve80is a ball valve so that there is minimal pressure drop therethrough. At an end of inlet line78is a threaded inlet connector82of a kind known in the art. Inlet connector82is adapted for connection to a hose coupling84on the end of inlet hose42.

Meter40is attached to a meter stand86mounted on floor66. For the illustrated meter40, pressure valve88forms part of the inlet of the meter. Pressure valve88is connected to inlet line78by a pressure valve line90. Pressure valve line90has a valve92herein so that the pressure valve line may be opened and closed as desired, although it is normally open. Pressure valve88is of a kind known in the art designed so that only liquid passes through meter40and no vapor or air goes through in order to insure the accuracy of the meter.

A pump outlet line94connects pump outlet76with pressure valve88of meter40. A flexible connector96may be included in pump outlet line94to compensate for any vibration from pump38and engine70.

Engine70has a fuel tank98which is preferably filled with some of the liquid, such as diesel fuel, being transferred. That is, a portion of the fuel is poured into fuel tank98. In this way, engine70is provided with fuel from the system without the necessity of a separate fuel source. It will be seen that this adds to the total portability and independent operation of system10. One preferred engine is the above-referenced 10 horsepower diesel engine with the Gorman-Rupp pump, but many types of engines could be used.

In addition to pressure valve88, meter40is illustrated as one having a resettable digital readout102and a printer104for printing the amount of liquid passing through it on any particular operation. One preferred meter is the Liquid Controls (LC) Model No. LC M-30-C-1, although the invention is not intended to be limited to any particular meter. In particular, it is not intended that the invention be limited to a meter having a pressure valve on the inlet thereof. Other types of meters designed for the liquid being transferred will work in addition to the one shown.

Meter40has an outlet106. An outlet line108is connected to meter outlet106. Outlet line108has an elbow110and an outlet valve112therein. Outlet valve112is preferably a ball valve for minimal pressure drop therethrough, but other types of valves could be used. The invention is not intended to be limited by any particular outlet valve design.

Outlet line108has a threaded outlet connector114on an end thereof. Outlet connector114is adapted for connection to a hose coupling116on outlet hose44.

Between outlet valve112and outlet connector114is an air line118in outlet line108. An air valve120in air line118allows control of communication between air line118and outlet line108. At an end of air line118is an air line connector122. Air line connector122is of a kind known in the art and is adapted for connection to an air coupling124at one end of an air hose126. The other end of air hose126is connectable to an air fitting128of a kind known in the art which is mounted on transport truck24and part of the standard air system of the truck.

System10also includes a monitoring system130, also referred to herein as monitor130, to alert the operator if the liquid level in tank32of transport trailer28exceeds a predetermined level. Transport trailer28has a standard electrical connector132thereon which is wired to an internal float switch134, both of which are part of the electrical system of transport truck24and powered thereby. A cable136connected to monitor130has a plug138thereon which is adapted for connection to electrical connector132. One known example of monitor130is the Scully Intellitrol Model No. 08909 IC-OG, although the invention is not intended to be limited to this particular monitoring system. In stationary applications, such monitors may be used to control valves in the pumping system, but this is not done in the portable system of the present invention. However, in system10an audible alarm131is connected to monitor130to alert the operator if the liquid level in transport trailer28is higher than desirable.

Also mounted in trailer46is a grounding cable140wound on a reel142. Grounding cable140is grounded to the rest of system10, such as to the piping and can be connected to a metal portion of transport trailer28to minimize the possibility of a static electrical spark when connecting system10for a pumping operation. Ordinarily, it is not necessary to connect grounding cable140because inlet hose42and outlet hose44preferably have metal wire woven therein so that they each act as grounding cables. Thus, grounding cable140is redundant in most cases, but is available if a grounded hose is not available.

OPERATION OF THE INVENTION

Referring now also to the flow schematic ofFIG. 5, the method of operation of diesel fuel transferring system10will be discussed.

A petroleum marketer may do a survey of available sources of supply of fuels, such as diesel fuel, and find that a particular supplier has a railcar16filled with the desired product at an attractive price. With the present invention, it does not matter whether railcar16is located at an unloading terminal. In fact, it might be learned that the price of the product will be lower if the railcar can be unloaded without having to wait for it to be moved to a terminal and further wait its turn for unloading. The present invention makes it possible to do the unloading anywhere that system10and a transport truck24can be positioned near the railcar and thus to obtain the optimum price for the product.

Prior to connection of system10, railcar valve22, inlet valve80, outlet valve112, transport valve36and air valve120are closed. Normally, valve92is left open and only closed when installing or doing maintenance on system10.

Once system10and transport truck24are positioned near a railcar16, connection of system10may be started. First, chocks144are placed for safety at each end of railcar16as seen inFIG. 1. Chocks144are easily stored in trailer46.

Inlet and outlet hoses42and44are also normally stored in trailer46. However, in some cases, inlet and outlet hoses42and44may alternatively be carried on transport trailer28in the same manner as any hose can be carried thereon. Either way, inlet hose42is taken out of storage and connected to railcar valve22in a known manner, and inlet hose coupling84is connected to inlet connector82on system10. Outlet hose44is taken out of storage and connected to transport valve36in a known manner, and outlet hose coupling116is connected to outlet connector114. Air hose126may be connected to air fitting128on transport trailer28, and air coupling124connected to air line connector122at this time, but this can be done later if desired.

Railcar valve22, inlet valve80, outlet valve112and transport valve36are then opened. If for some reason, valve92has been closed, it is opened as well. Air valve120is left closed at this time.

Diesel engine70is started and its clutch, if any, engaged automatically or manually to start driving pump38. It will be seen by those skilled in the art that system10thus acts to pump liquid out of railcar16and into transport trailer28. Since the electrical and air systems are carried normally on transport truck24, and because engine70uses the same fuel as that in system10, the entire system is self-contained. The only limitation is that the operator be able to get system10and transport trailer28close enough to railcar16so that the connections can be made.

The operator can watch meter readout102to determine when enough liquid has been transferred. Monitor130will act to warn the operator if transport trailer28is being overfilled.

When the desired amount of liquid has been loaded into transport trailer28and no more is to be unloaded from railcar16, engine70is shut off to stop pump38and railcar valve22is closed. Inlet hose42is disconnected from railcar valve22, and that end of the inlet hose is raised to allow the liquid therein to drain toward inlet valve80. Engine70is restarted and pump38thereby allowed to operate a little longer in order to evacuate the liquid from inlet hose42, at which point engine70is again shut off. At this time, inlet valve80and outlet valve112are closed. If further unloading of railcar16will be done at this time, it is not necessary to close railcar valve22or disconnect inlet hose42. Also, it will be seen that if railcar16is emptied during the transfer operation, inlet hose42will be evacuated by leaving the pump running a few moments longer, thus making the manual draining step described above unnecessary. In any event, when disconnecting inlet hose42, it is important to get the liquid out of inlet hose42to make it easier to handle for storage and to avoid any spillage of liquid into the environment.

If air hose126has not yet been installed as previously described, this step is done after pumping and closing of outlet valve112. Air valve120is then opened, and air pressure from the truck air system is applied to outlet hose44to force any liquid therein out of the outlet hose, through transport valve36and into tank32of transport trailer28. Once outlet hose44is thus emptied, air valve120is closed and air hose126disconnected. Air valve120may then be reopened to vent any air pressure from outlet hose44, after which the air valve is closed again.

Any time after railcar valve22and inlet valve80are closed following an unloading operation, inlet hose42may be disconnected from the railcar valve and inlet connector82and stored again in trailer46or on transport trailer28. Because the liquid was pumped out of inlet hose42as previously described, the inlet hose is not too heavy to handle and no significant amount of liquid is spilled into the environment. After the air pressure procedure described above, outlet hose44may be disconnected from outlet connector114and transport valve36and stored again in trailer46or on transport trailer28. Because the liquid was blown out of inlet hose42by air, the outlet hose is not too heavy to handle and no significant amount of liquid is spilled into the environment.

After disconnecting cable136from transport trailer28and, if necessary, disconnecting grounding cable140, the unloading operation is complete. Transport truck24can then be driven to the desired point of distribution of the petroleum in it. System10can be used to further unload railcar16into another transport truck or easily moved to another location to unload a different railcar.

It will be seen, therefore, that the fuel transferring system and method of determining and obtaining a source of supply of petroleum products of the present invention are well adapted to carry out the ends and advantages mentioned as well as those inherent therein. While presently preferred embodiments of the system and method have been described for the purposes of this disclosure, numerous changes in the arrangement and construction of parts in the system and steps in the method may be made by those skilled in the art. All such changes are encompassed within the scope and spirit of the appended claims.