Patent Application
20210260500
The present disclosure generally relates to water drainage from fuel systems of a machine, and more particularly, to fuel systems of locomotives.
In fuel systems, such as those on locomotive engines, water is removed from the fuel supplied to engines in order to reduce the risk of corrosion and reduced performance of the engine and its related components. Fuel-water separators are typically used to remove water from the fuel prior to delivery to the engine. The liquid (primarily water) that has been separated out from the fuel by the fuel-water separator generally accumulates in the fuel-water separator and, at some point, is released and directed into a waste tank. Such release of such liquid from the fuel-water separator is typically controlled by a sensor and a magnetic valve. The sensor activates when such liquid reaches a certain level in the fuel-water separator and triggers the magnetic valve to open to release the accumulated liquid out of the fuel-water separator for routing to the waste tank for subsequent disposal. Alternatively, a manual drain cap may be utilized.
Ideally, the liquid separated and released into the waste tank comprises only water. However, while such liquid primarily includes water, the liquid may also include, and often does, some amount of fuel. This leads to a loss of fuel to the fuel system. Also, with time and use the magnetic valve can become stuck/frozen in the open or closed position. When stuck in the open position, a drop in pressure is experienced in the fuel-water separator, which can result in a pressure drop in the common rail fuel system that delivers fuel to the engine. Such a drop in pressure may adversely effect engine performance. When stuck in the closed position, the accumulated water is not released and may back up within the fuel-water separator, adversely effecting performance. Eventually, fuel mixed with water may reach the engine and its components. Similar problems may be experienced with the manually operated drain cap because such drain cap over time and use may become stuck in the closed position.
U.S. Pat No. 7,655,140, issued Feb. 2, 2010, discloses a fuel-water separator system that includes a fuel tank for storing fuel and a fuel-water separator fluidly coupled to the fuel tank fir separating water from the fuel. The fuel pump has a suction side that is fluidly coupled to the fuel-water separator for pumping fuel from the fuel-water separator. The fuel pump has a high pressure side where the fuel has a higher pressure than at the suction side. A water pump, such as a venturi or a jet pump, is fluidly coupled between the fuel-water separator and the fuel tank for pumping the water from the fuel water separator into the fuel tank. The water pump is fluidly coupled to the high pressure side of the fuel pump to receive the fuel at the higher pressure to drive the water pump. While beneficial, a better system is needed.
In one aspect of the present disclosure, a continuous flow system for draining a fuel-water separator is provided. The fuel-water separator is configured to separate water from fuel in a fluid received by the fuel-water separator and to output a first separated liquid that comprises water. The system may comprise a return conduit fluidly connecting the fuel-water separator to a fuel tank. The return conduit may be configured to deliver the first separated liquid received from the fuel-water separator to the fuel tank. The fuel-water separator is in continuous fluid communication with the fuel tank through the return conduit.
In another aspect of the disclosure, a method for assembling a continuous flow system for draining a fuel-water separator on a locomotive is disclosed. The method may comprise coupling a fuel-water separator to a fuel tank of the locomotive with conduit, the fuel-water separator in continuous fluid communication with the fuel tank through the return conduit. The fuel-water separator is configured (a) to separate water from fuel in a fluid received by the fuel-water separator and (b) to output a first separated liquid that comprises water. The return conduit is configured to deliver the first separated liquid received from the fuel-water separator to the fuel tank.
In yet another aspect of the disclosure, a continuous flow system for draining a fuel-water separator disposed on a locomotive is disclosed. The locomotive includes a fuel tank and the fuel-water separator. The fuel-water separator has an input port, a drain port and an output port. The fuel-water separator is configured to separate water from fuel in a fluid received by the fuel-water separator through the input port and to output through the drain port a first separated liquid that comprises water, and to output through the output port a second separated liquid that comprises fuel. The continuous flow system may comprise a return conduit fluidly connecting the drain port of the fuel-water separator to the fuel tank of the locomotive. The return conduit is configured to deliver the first separated liquid received from the fuel-water separator to the fuel tank, the fuel-water separator in continuous fluid communication with the fuel tank through the return conduit.
Reference will now be made in detail to specific embodiments or features, examples of which are illustrated in the accompanying drawings. Generally, corresponding reference numbers will be used throughout the drawings to refer to the same or corresponding parts, unless otherwise specified.
The fuel tank 128 is configured to hold fuel and is in fluid communication with the fuel-water separator 132. A fuel pump 130 is fluidly connected to the fuel tank 128 and an input port 142 of the fuel-water separator 132. The fuel pump 130 is configured to pump fluid out of the fuel tank 128 to deliver such fluid to the input port 142 of the fuel-water separator 132 via the input fuel line 138. The fluid pumped out of the fuel tank 128 comprises fuel, but often may comprise fuel and some volume of water.
The fuel-water separator 132 may include the input port 142, a drain port 144 and an output port 146 disposed in a body 148. As is known in the art, the fuel-water separator 132 is configured to separate water from fuel in a fluid received by the fuel-water separator 132 through the input port 142. The fuel-water separator 132 is further configured to provide through the drain port 144 a first separated liquid that comprises water, and to provide through the output port 146 a second separated liquid that comprises fuel.
The high pressure common rail pump 134 includes an inflow fuel port 166 and an outflow fuel port 168. The inflow fuel port 166 of the high pressure common rail pump 134 is fluidly connected to the output port 146 of the fuel-water separator 132. The outflow fuel port 168 of the high pressure common rail pump 134 is fluidly connected to the fuel injectors 124 of the engine 120. The high pressure common rail pump 134 is configured to suction under high pressure the second separated liquid (that comprises fuel) out of the output port 146 and deliver such second separated liquid to the fuel injectors 124 of the engine 120.
The continuous flow system 136 for draining the fuel-water separator 132 includes a return conduit 150 fluidly connecting the drain port 144 of the fuel-water separator 132 to the fuel tank 128. The return conduit 150 is configured to continuously deliver the first separated liquid (that comprises water) received from the fuel-water separator 132 to the fuel tank 128 such that the fuel-water separator 132 is in continuous fluid communication with the fuel tank 128 through the return conduit 150. For example, during operation of the fuel-water separator 132, the return conduit 150 is configured to provide a continuous flow of the first separated liquid from the fuel-water separator 132 to the fuel tank 128.
Turning now to
The receiving conduit 152 has a receiving diameter R. The receiving diameter R may vary along the length of the receiving conduit 152. The receiving conduit 152 includes a receiving transition portion 158 disposed adjacent to the orifice 156. The receiving transition portion 158 may, in some embodiments, be frustoconical in shape. As used herein, the receiving diameter R is measured for the receiving conduit 152 at a point outside of the receiving transition portion 158 since, in some embodiments, the receiving transition portion 158 may narrow to the same diameter as the orifice diameter O in the area near where the receiving transition portion 158 meets or is adjacent to the orifice 156.
The delivering conduit 154 has a delivering diameter D. The delivering diameter D may vary along the length of the delivering conduit 154. The delivering conduit 154 includes a delivering transition portion 160 disposed adjacent to the orifice 156. The delivering transition portion 160 may, in some embodiments, be frustoconical in shape. As used herein, the delivering diameter D is measured for the delivering conduit 154 at a point outside of the delivering transition portion 160 since, in some embodiments, the delivering transition portion 160 may narrow to the same diameter as the orifice diameter O in the area near where the delivering transition portion 160 meets or is adjacent to the orifice 156.
The orifice 156 has an orifice diameter O that is less than the receiving diameter R. The orifice diameter O may also be less than the delivering diameter D. In some embodiments, such as the embodiment shown in
In an embodiment, the orifice 156 may he so dimensioned so that the continuous flow of the first separated liquid out of the fuel-water separator 132 does not result in a pressure drop of more than 0.8% in the second separated liquid (that comprises fuel) delivered to the fuel system 122, as measured before (and proximal to) the inflow fuel port 166 (see
The return conduit 150 defines a flow path 162 for the first separated fluid extending from the (open) drain port 144 of the fuel-water separator 132 to the fuel tank 128. The flow path 162 is free from obstruction, meaning that the flow path 162 is configured so that the first separated fluid flowing out of the fuel-water separator 132 through the return conduit 150 is not blocked from flowing (e.g., not blocked by a valve that is closed or a drain cap disposed over the drain port 144); in other words the flow path 162 of the first separated fluid in the return conduit 150 is free from obstruction by a valve, drain cap or the like).
Also disclosed is a method for assembling a continuous flow system 136 for draining a fuel-water separator 132 on a locomotive 102. The method may comprise coupling a fuel-water separator 132 to a fuel tank 128 of the locomotive 102 with a return conduit 150, the fuel-water separator 132 in continuous fluid communication with the fuel tank 128 through the return conduit 150, wherein the fuel-water separator 132 is configured (a) to separate water from fuel in a fluid received by the fuel-water separator 132 and (b) to output a first separated liquid that comprises water, wherein the return conduit 150 is configured to deliver the first separated liquid received from the fuel-water separator 132 to the fuel tank 128.
In operation, the fuel-water separator 132 receives fluid at the input port 142. The fluid includes fuel and may further include water. The fuel-water separator 132 separates the fluid into a first separated liquid that comprises water and a second separated liquid that comprises fuel (or is fuel). The second separated liquid exits the fuel-water separator 132 via the output port 146 and is pumped, for example, by the high pressure common rail pump 134, to the fuel injectors 124 of the engine 120 of, for example, a locomotive 102. The first separated liquid exits the fuel-water separator 132 via the drain port 144 and flows into and through the return conduit 150 to the fuel tank 128 in a continuous flow or dripping flow. The return conduit 150, as discussed herein, includes a receiving conduit 152, a delivering conduit 154, and an orifice 156. The orifice 156 is so dimensioned as (a) to provide continuous flow or dripping of the first separated liquid (delivered by the orifice 156) into the delivering conduit 154 and (b) to maintain a substantially constant pressure at the inflow fuel port 166 of the high pressure common rail pump 134 or result in a variance of 0-0.8% pressure drop during operation of the fuel-water separator 132 (as measured at the inflow fuel port 166 of the high pressure common rail pump 134).
In general, the foregoing disclosure finds utility in various applications relating to draining of the first separated liquid (that comprises water) from fuel-water separators 132. More specifically, the disclosed continuous flow system 136 may be used to drain fuel-water separators 132 of locomotives 102 or the like without an adverse effect on the pressure of the second separated liquid (that comprises fuel) provided at the inflow fuel port 166 of the high pressure common rail pump 134. This reduces the maintenance and adverse effects of traditional systems (for controlling the discharge of separated fluid comprising water from fuel-water separators 132), which have valves, drain caps or the like that become stuck/frozen in an open or closed position. When such valves or drain caps are frozen in a closed position, damage to the fuel system 122 and its components may occur. When stuck in the open position, the fuel system 122 and engine 120 may become inefficient or experience loss in power.
From the foregoing, it will be appreciated that while only certain embodiments have been set forth for the purposes of illustration, alternatives and modifications will be apparent from the above description to those skilled in the art. These and other alternatives are considered equivalents and within the spirit and scope of this disclosure and the appended claims.
