Fuel valve and engine with same

Abstract

A fuel valve (30) for a large two-stroke turbocharged uniflow scavenging internal combustion engine and such an engine comprising a fuel valve (30). The fuel valve (30) includes an elongate fuel valve body (32) and a nozzle body (40) releasably attached to the fuel valve body (30). The elongate valve member (35) is axially displaceable between a closed position and an open position. The valve member (35) comprises a proximal end portion (35a) and a distal end portion (35b), the distal end portion (35b) being arranged to axially move in unison with the proximal end portion (35a) between a closed position and an open position, the distal end portion (35b) being arranged to be radially displaceable relative to the proximal end portion (35a).

Description

Technical Field

[0001] This disclosure relates to a fuel valve for injecting liquid fuel into the cylinder of a large turbocharged two-stroke single-flow scavenging internal combustion engine, and an engine having such a fuel valve. Background Technology

[0002] Large turbocharged two-stroke single-flow scavenging crosshead internal combustion engines are typically used as prime movers in large ocean-going vessels such as container ships or in power plants.

[0003] These engines' cylinders are equipped with: a single exhaust valve centrally located in the cylinder head, i.e., at the top of the cylinder; and a ring of piston-controlled scavenge ports located in the lower region of the cylinder liner. Accordingly, the gas flowing through the cylinder is directed from bottom to top, thus constituting a single-flow scavenging. The scavenging ports are angled to create vortices in the gas within the combustion chamber.

[0004] Two or three fuel valves are arranged around a centrally located exhaust valve in the cylinder head, with the fuel valve nozzles extending into the combustion chamber. Alternatively, the fuel valves may be positioned peripherally (not centrally) in the cylinder head, with the nozzle orifices generally aligned with the swirl direction, away from the cylinder wall and pointing towards the combustion chamber. Sometimes, a single nozzle orifice points towards the swirl in the combustion chamber.

[0005] The nozzle is attached to the front or distal end of the fuel valve body. The fuel valve includes an elongated body having a proximal or rear end extending from the upper surface of the cylinder head, and the elongated fuel valve body extends through the cylinder head, with a nozzle at the front or distal end of the elongated fuel valve body that extends into the combustion chamber.

[0006] Known nozzles for large, crosshead-type two-stroke diesel engines typically have a nozzle body comprising a cylindrical portion with a main nozzle orifice extending from the base of the nozzle at the proximal end of the nozzle body to a nozzle orifice located near the distal or distal end of the nozzle body. The distal or distal end can be rounded or flattened, but is closed, as the nozzle orifice should not point downwards toward the piston (when the piston is at top dead center (TDC), i.e., the moment of fuel injection in a compression-ignition engine, the upper surface of the piston is very close to the distal end of the nozzle due to the high compression ratio). Typically, each nozzle has three to seven nozzle orifices, all connected to the main orifice. These valves typically have a movable valve member (also called a "spindle") that mates with a conical valve seat located within the fuel valve body. In the closed position, the movable valve member rests on the valve seat, preventing fuel from flowing to the nozzle orifice; in the open position, the movable valve member is lifted from the valve seat, allowing fuel to flow to the nozzle orifice. Therefore, known fuel valves typically feature an axially displaceable valve member (spindle) that mates with a conical valve seat to control fuel flow toward the nozzle. Furthermore, the front portion of the spindle usually includes a distal cylinder that is tightly received within the main bore. When the spindle is in the closed position, this distal cylinder acts as a sliding valve to close the nozzle orifice, thereby reducing the so-called sac volume—the volume of fuel remaining in the space formed by the main bore in the nozzle. Without such a sliding valve arrangement, after a fuel injection event, the residual fuel volume in the main bore (and nozzle orifice) would drip into the combustion chamber, which would adversely affect fuel consumption, reliability, and emissions, for example, due to incomplete or unburned combustion of fuel in the exhaust gases.

[0007] However, the combination of a valve seat within the valve body that mates with a movable valve member and a sliding valve assembly formed by the slightly distal end of the movable valve member that mates with a main orifice in the nozzle is a relatively complex and expensive structure. Furthermore, there is still a desire to further reduce the bladder volume, especially for fuels such as ammonia, because unburned ammonia will cause ammonia slippage in the exhaust gas, potentially exceeding acceptable limits.

[0008] EP0744007A1 discloses a fuel valve for injecting liquid fuel into the combustion chamber of a large, two-stroke, turbocharged, single-flow scavenging internal combustion engine with a crosshead. This fuel valve typically includes: an elongated fuel valve body extending axially between a proximal end and a distal end, and a nozzle body extending axially from a base located at the proximal end of a nozzle body to the distal end of the nozzle body. The nozzle body is releasably attached to the fuel valve body, with its base connected to the distal end of the fuel valve body. A valve main orifice extends axially within the fuel valve body and opens to the distal end of the fuel valve body. The nozzle main orifice opens to the proximal end of the nozzle body and extends axially toward the distal end of the nozzle body, terminating at a valve seat. The elongated valve member is axially displaceable between a closed position and an open position, in which the valve member rests on the valve seat and in the open position, the valve member is lifted from the valve seat. When the valve assembly is raised, the main nozzle orifice is fluidly connected to multiple nozzle orifices; when the valve assembly is lowered, the main nozzle orifice is fluidly disconnected from the nozzle orifices. The valve assembly typically includes a proximal portion and a distal portion, the distal portion being configured to move axially between a closed position and an open position in sync with the proximal portion. Summary of the Invention

[0009] In view of the above, the object of the present invention is to provide a fuel valve for injecting liquid fuel into a large two-stroke single-flow scavenging internal combustion engine of the crosshead type, so as to overcome or at least reduce the above-mentioned problems.

[0010] The above and other objectives are achieved through the features of the independent claims. Further implementations are readily apparent from the dependent claims, the specification, and the drawings.

[0011] According to a first aspect, a fuel valve is provided for injecting liquid fuel into the combustion chamber of a large, two-stroke, turbocharged, single-flow scavenging internal combustion engine having a crosshead, the fuel valve comprising:

[0012] - An elongated fuel valve body that extends axially between its proximal and distal ends.

[0013] - Nozzle body, the nozzle body extending axially from a base located at the proximal end of the nozzle body to the distal end of the nozzle body, the nozzle body being releasably attached to an elongated fuel valve body, wherein the base is connected to the distal end of the valve body.

[0014] - The valve main bore extends axially within the valve body and leads to the distal end of the valve body.

[0015] - Nozzle main bore, which leads to the proximal end of the nozzle body, and nozzle main bore that extends axially from the proximal end of the nozzle body toward the distal end of the nozzle body into the nozzle body and terminates in a valve seat within the nozzle body.

[0016] - An elongated valve component, capable of axial displacement between a closed position and an open position. In the closed position, the elongated valve component rests on the valve seat; in the open position, the elongated valve component is lifted off the valve seat.

[0017] - When the elongated valve member is lifted from the valve seat, the main nozzle orifice is fluidly connected to multiple nozzle orifices; and when the elongated valve member rests on the valve seat, the main orifice is fluidly disconnected from the multiple nozzle orifices.

[0018] - The elongated valve member includes a proximal portion and a distal portion, the distal portion being configured to move axially between a closed position and an open position in accordance with the proximal portion, and the distal portion being configured to be radially displaced relative to the proximal portion.

[0019] The most direct solution to reduce complexity and bladder volume is to construct a fuel valve in which the main shaft guide and atomizer body are monolithic components. However, the absence of a separate atomizer body is considered disadvantageous. The atomizer body cannot be replaced without replacing the main shaft guide because it protrudes into the combustion chamber, exposing it to very high external temperatures, while the fuel flowing through it is relatively cold. This creates significant thermal stress on the atomizer body, resulting in a much shorter lifespan for the atomizer body compared to the main shaft guide. Consequently, the nozzle may need to be replaced several times during the fuel valve's lifespan, while the main shaft guide may not require replacement.

[0020] However, it is technically impossible to combine a separate sprayer body with a valve seat located inside the sprayer with a spindle that requires 100% concentricity between the spindle guide and the sprayer, because the nozzle body cannot be reattached to the spindle guide in a manner that ensures perfect alignment between the guide hole of the nozzle body and the guide hole of the spindle guide.

[0021] The inventors believe it is advantageous to construct the main shaft from two independent parts: a proximal portion and a distal portion. The connection between the proximal and distal portions allows them to move axially in unison to control the opening and closing of the fuel valve. However, the distal portion can be at least slightly radially displaced relative to the proximal portion, so that the orifice in the nozzle body guiding the distal portion does not need to be perfectly aligned with the orifice in the main shaft guide guiding the main shaft. Therefore, the main shaft has a two-piece structure, with a distal portion mating with the nozzle and a proximal portion mating with the main shaft guide. In this way, the entire main shaft guide does not need to be replaced each time the sprayer needs to be changed.

[0022] Among the possible implementations of the first aspect,

[0023] - The proximal portion is at least partially received within the valve main bore, preferably, the axial movement of the proximal portion is guided by the valve main bore, and

[0024] - wherein the distal portion is at least partially received in the nozzle main bore, and preferably, the axial movement of the distal portion is guided by the nozzle main bore.

[0025] In a possible implementation of the first aspect, at the junction between the proximal and distal portions, the proximal end of the distal portion engages with the distal end of the proximal portion, and the junction allows the distal portion to be radially displaced relative to the proximal portion.

[0026] In a possible implementation of the first aspect, the joint includes a positive mechanical joint connection, wherein the design and geometry of the joint are such that it will not open or disengage under the action of any force or component of force during normal use or testing.

[0027] In a possible implementation of the first aspect, the form-fitting mechanical joint includes a recess, a protrusion received in the recess, preferably the recess includes a deep portion that is wider than the shallow portion, and the protrusion includes a head that is wider than the neck that supports the head.

[0028] In a possible implementation of the first aspect, the proximal end of the distal portion and the distal end of the proximal portion together form a form-fitting mechanical joint connection.

[0029] In a possible implementation of the first aspect, the distal portion is releasably connected to the proximal portion via a form-fitting mechanical engagement connector.

[0030] In a possible implementation of the first aspect, the distal end of the proximal portion includes a first abutting surface, and wherein the proximal end of the distal portion includes a second abutting surface, and wherein the first abutting surface abuts against the second abutting surface, preferably, the first abutting surface abuts against the second abutting surface by fuel pressure acting on the distal portion, the fuel pressure pushing the distal portion toward the proximal portion, thereby pressing the second abutting surface against the first abutting surface.

[0031] In a possible implementation of the first aspect, the first abutting surface abuts against the second abutting surface to form a fluid seal.

[0032] In a possible implementation of the first aspect, the distal end of the proximal portion is provided with a hole, and the proximal end of the distal portion is received in the hole.

[0033] In a possible implementation of the first aspect, the elongated fuel valve body includes a distal portion that is releasably attached to the remainder of the fuel valve body. Preferably, the distal portion of the elongated fuel valve body is releasably attached to the remainder of the fuel valve body via a first sleeve that is threadedly engaged with the remainder of the fuel valve body.

[0034] In a possible implementation of the first aspect, the nozzle is releasably attached to the elongated fuel valve body via a second sleeve, the second sleeve being threadedly engaged with the elongated fuel valve body.

[0035] In a possible implementation of the first aspect, the proximal portion includes a first shaft, and the distal portion includes a second shaft, preferably including one or more axially extending fuel grooves.

[0036] In a possible implementation of the first aspect, the distal portion has a distal end that rests on the valve seat when the elongated valve member is in the closed position. Preferably, the distal end of the distal portion has a shape complementary to the shape of the valve seat, such that no fuel can flow through the valve seat when the elongated valve member is in the closed position.

[0037] In a possible implementation of the first aspect, the nozzle main orifice leads to the proximal end of the nozzle and is fluidly connected to the valve main orifice leading to the distal end of the valve body for receiving liquid fuel from the fuel valve.

[0038] In a possible implementation of the first aspect, the elongated valve member moves toward the proximal end of the fuel valve to achieve lifting; preferably, the elongated valve member moves toward the proximal end of the fuel valve against the bias of the elastic member to achieve lifting.

[0039] In a possible implementation of the first aspect, the lifting of the elongated valve member is caused by fuel pressure acting on the elongated valve member.

[0040] In one possible implementation of the first aspect, the fuel chamber surrounds the distal end of the proximal portion.

[0041] In a first possible aspect, the fuel valve includes a backup valve seat configured to operate together with a backup sealing surface, the backup valve seat being disposed in an elongated valve body, the backup sealing surface being formed on a proximal portion, the backup valve seat and the backup sealing surface being configured to be raised when the elongated valve member is in an open position, a closed position, or any position between the open and closed positions, and wherein, when the elongated valve member is in a position further than the position where the distal end of the distal portion rests on the valve seat, the backup valve seat rests on the backup valve sealing surface.

[0042] According to a second aspect, a large two-stroke turbocharged single-flow scavenging internal combustion engine with a crosshead is provided, including a fuel valve according to the first aspect and any possible implementation thereof.

[0043] These and other aspects of the invention will become apparent from the embodiments described below. Attached Figure Description

[0044] In the following detailed sections of this disclosure, the invention will be explained in more detail with reference to exemplary embodiments shown in the accompanying drawings, in which:

[0045] Figure 1 This is a top view showing the front end and a lateral side of a large two-stroke unit-flow scavenged turbocharged engine according to an exemplary embodiment.

[0046] Figure 2 It shows Figure 1 A top-down view of the rear end and another lateral side of the engine.

[0047] Figure 3 It is based on Figure 1 A schematic diagram of the engine and its intake and exhaust systems.

[0048] Figure 4 It is used in Figures 1 to 3 A top-down view of the implementation of the fuel valve used in the engine.

[0049] Figure 5 yes Figure 4 A cross-sectional view of the fuel valve.

[0050] Figure 6 yes Figure 4 A cross-sectional view of the fuel valve after the nozzle has been removed.

[0051] Figure 7 yes Figure 4 A top-down view of the elongated valve component of the fuel valve.

[0052] Figure 8 yes Figure 7 A top-view view of an elongated valve component, wherein the proximal and distal portions of the elongated valve component are separated.

[0053] Figure 9 yes Figure 4 A cross-sectional view of the nozzle body of the fuel valve.

[0054] Figure 10 yes Figure 4 A cross-sectional view of the valve body (main shaft guide), movable valve component, and distal portion of the nozzle body of the fuel valve.

[0055] Figure 11This is when the valve component is in the closed position. Figure 4 A cross-sectional view of the valve body (main shaft guide), movable valve component, and distal portion of the nozzle body in another embodiment of the fuel valve.

[0056] Figure 12 This is when the raised valve component is in the open position. Figure 11 A cross-sectional view of the distal portion of the valve body (spindle guide), movable valve component, and nozzle body.

[0057] Figure 13 yes Figure 4 A cross-sectional view of the valve body (main shaft guide), movable valve component, and distal portion of the nozzle body in another embodiment of the fuel valve.

[0058] Figure 13A yes Figure 13 Detailed view of part A in the image.

[0059] Figure 13B yes Figure 13 Detailed views of part B in the document, and

[0060] Figure 14 Viewed from the piston side Figure 4 A schematic diagram showing the location of the fuel valve nozzle within the engine cylinder head, and illustrating the orientation of the nozzle orifice and the resulting fuel jet. Detailed Implementation

[0061] In the following detailed description, a fuel valve 30 and a large two-stroke turbocharged single-flow scavenging internal combustion engine using the fuel valve 30 will be described by way of exemplary embodiments. Figures 1 to 3 A large, low-speed turbocharged two-stroke internal combustion engine with crankshaft 22 and crosshead 23 is shown. Figure 3 A schematic diagram of a large, low-speed, turbocharged two-stroke internal combustion engine and its intake and exhaust systems is shown. In this exemplary embodiment, the engine has six cylinders inlined (formed by cylinder liners 1). Large turbocharged two-stroke internal combustion engines typically have between five and sixteen cylinders inlined, carried by an engine frame 24. This engine can be used, for example, as a main engine in ocean-going vessels, or as a stationary engine in a power plant for operating generators. The total output of the engine can, for example, be in the range of 5,000 kW to 110,000 kW.

[0062] The engine can be a two-stroke, single-flow diesel (compression ignition) engine, having: a scavenging port 19, which is in the form of a piston-controlled port in the lower region of the cylinder liner 1; and an exhaust valve 4 at the top of the cylinder liner 1. Therefore, during the engine cycle, the flow within the combustion chamber 14 is from bottom to top, thus the engine is a so-called single-flow type. Scavenging air is delivered from the scavenging air receiver 2 to the scavenging air ports 19 of the individual cylinders formed by the cylinder liner 1. The reciprocating piston 21 in the cylinder liner 1 compresses the scavenging air, and fuel is injected via nozzles of two or three fuel valves 30 disposed in the cylinder head 26. Combustion ensues, generating exhaust gases. When the exhaust valve 4 is open, the exhaust gases flow through the exhaust pipe 20 associated with the cylinder 1 and concerned into the exhaust gas receiver 3, and flow forward through the first exhaust pipe 18 to the turbine 6 of the turbocharger 5, from which the exhaust gases exit through the second exhaust pipe 7. The turbine 6 drives the compressor 9 supplied via the air inlet 10 through the shaft 8.

[0063] Compressor 9 delivers pressurized filling air to filling air duct 11 leading to filling air receiver 2. Scavenging air in duct 11 passes through intercooler 12 for cooling the filling air. The cooled filling air is then delivered to filling air receiver 2 via auxiliary blower 16 driven by electric motor 17, which pressurizes the filling air flow under low or partial load conditions. Under higher loads, turbocharger compressor 9 delivers fully compressed scavenging air, which is then bypassed by auxiliary blower 16 via check valve 15.

[0064] The cylinder is formed in the cylinder liner 1. The cylinder liner 1 is supported by the cylinder frame 25, which is supported by the engine frame 24.

[0065] Figure 14 The diagram illustrates how the nozzle 40 is positioned peripherally within the cylinder head 26 around the exhaust valve 4, and the direction of the fuel jet from the main nozzle orifice 45 in the nozzle 40 is shown by fine dotted lines. The angled diffusion direction of the fuel jet is indicated by discontinuous double arrows. Typically, at least four nozzle orifices 45 are present. Typically, each cylinder is provided with three (as shown) or four fuel valves 30. In a dual-fuel engine, there will be an additional three or four fuel valves (not shown) for injecting other fuels while the current fuel valve 30 is only used for pilot fuel injection. The direction of the gas vortex in the combustion chamber 14 is indicated by curved discontinuous arrows 96.

[0066] Figures 4 to 10A first embodiment of two to four fuel valves 30 installed in the through holes of the cylinder head 26 of each cylinder 1 is shown, wherein the rear (proximal) end 31 of the fuel valve 30 protrudes from the upper side of the cylinder head 26, and the distal end (slight end) of the fuel valve, i.e. the nozzle 40, protrudes into the combustion chamber.

[0067] Fuel valve 30 includes an elongated fuel valve body 32 with a nozzle 40 releasably connected to a distal (front) end 33. The elongated fuel valve body 32 extends axially between a proximal end 31 and a distal end 33. The valve body 32 may be assembled from several parts; in this embodiment, the distal portion of the valve body 32 is formed by a spindle guide 89. In this embodiment, a spring guide 99 is also present as part of the valve body 32. The spring guide 99 and the spindle guide 89 are releasably attached to the remainder of the fuel valve body 32 via a first sleeve 88, which is threadedly engaged with the remainder of the valve body 32. However, it should be understood that this is only an example, and the valve body 32 may include fewer or more parts depending on the requirements of the application using the valve body 32. Liquid fuels (such as ammonia, ethanol, methanol, diesel, or heavy fuel oil) are delivered from fuel valve 30 to combustion chamber 14 in a controlled and timed manner via nozzle 40. The fuel valve 30 has an elongated body 32 with a head at its proximal end 31. The fuel valve 30 can be mounted in the cylinder head 26 in a known manner via this head, for example, by means of bolts extending through an orifice of flange 60 into a threaded hole in the cylinder head 26. The fuel valve 30 is connected to a liquid fuel source for the internal combustion engine. A hydraulically actuated liquid source, acting at a controlled pressure on a booster in the fuel valve 30 (described in more detail below), increases the fuel pressure at the start of a fuel injection event and decreases the pressure at the end of the fuel injection event. The opening and closing of the fuel valve 30 is caused and controlled by this increase and decrease in the fuel pressure supplied to the fuel valve. Typical maximum fuel injection pressures are above 200 bar, preferably above 300 bar. It should be noted that this embodiment shows the fuel valve 30 including a booster, but it should be understood that the fuel valve 30 can also be operated without a booster, the fuel supplied to the fuel valve 30 has sufficient pressure, and the fuel supplied to the fuel valve 30 has a controlled increase in pressure when fuel needs to be injected into the combustion chamber 14 and a controlled decrease in pressure when fuel does not need to be injected into the combustion chamber 14.

[0068] The head at the proximal end 31 includes an actuation port 83, which is fluidly connected to a hydraulic system configured to increase pressure when a fuel injection event is required and to decrease pressure when the fuel injection event is complete. The operating system is controlled by an electric motor control system. The actuation port 83 is connected to the pressure chamber of a booster, which includes a plunger having a large diameter on its actuation port-facing side and a smaller diameter on its opposite end facing the pump chamber 80. Therefore, the pressure in the actuation port 83 is multiplied by the ratio between the effective areas defined by the respective diameters of the plunger. The pump chamber 80 is connected to a boosted fuel source, for example, pressurized to approximately 10 bar, via a one-way valve device 85. This one-way valve device 85 allows fuel to enter the pump chamber 80 from the boosted fuel source but prevents fuel from flowing from the pump chamber 80 back to the fuel source. The one-way valve device 85 also allows fuel to flow from the pump chamber 80 to a valve seat 46 located at the distal end of the nozzle body 40.

[0069] An axially displaceable elongated valve member 35 (main shaft) is pivoted within the valve housing 32 and has an open position, an intermediate position, and a closed position. In the open position, the valve member 35 is raised from a preferably tapered valve seat 36. In the intermediate position, the valve member 35 is raised from the seat 36. In the closed position, the mating or complementary portion 36 at the distal end of the valve member 35 rests in a sealing manner on the valve seat 46. The main shaft 35 is elastically biased toward the closed position by an elastic device, in this embodiment, formed by a helical spring 87 acting on a pusher 79 acting on the distal end of the main shaft 35. The pressure of fuel supplied to the space 68 surrounding the main shaft 35 and acting on a first surface of the main shaft 35 generates a force in the proximal direction that overcomes the force generated by the helical spring 87 in the distal direction, thereby raising the main shaft 35 against the bias of the helical spring 87.

[0070] The elongated valve component (main shaft) 35 is longitudinally divided into a proximal portion 35a and a distal portion 35b. A space 68 is fluidly connected to the distal end of the main shaft 35 via a groove 37 extending axially on the outer surface of the distal portion 35b, and this space 68 forms a fuel chamber.

[0071] The fuel valve 30 carries a nozzle 40 at its distal end 33. The nozzle 40 is configured to extend into the combustion chamber 14 of the engine cylinder liner 1 and to inject fuel into the combustion chamber 14 through a nozzle orifice 45.

[0072] The furthest portion of the elongated fuel valve body 32 is formed by a spindle drive 89. The spindle guide 89 is releasably attached to the remainder of the elongated fuel valve body 32 via a first sleeve 88, which is threadedly engaged with the remainder of the elongated fuel valve body 32. The nozzle body 40 is releasably attached to the spindle guide 89 via a second sleeve 49, which is threadedly engaged with a portion of the spindle guide 89.

[0073] In this embodiment, the fuel valve 30 includes an axially displaceable elongated valve member 35 in the form of a spindle. The elongated valve member 35 includes a tapered portion 36 at its distal end, which mates with a tapered seat 46 near the distal end of the nozzle body 40. It should be understood that the valve seat 46 and the surfaces on the distal ends of the elongated valve member 35 that mate with it do not need to be tapered. Other shapes can achieve the same purpose, provided that the two surfaces are complementary or at least mating when the spindle 35 rests on the valve seat 46 to form a leak-proof valve seat. The elongated valve member 35 (spindle) includes a proximal portion 35a and a distal portion 35b. The proximal portion 35a and the distal portion 35b are configured to align axially in the open position with... Figure 10 The main shaft 35 moves between the indicated closed positions, in which the main shaft 35 is not raised and the tapered portion 36 at the distal end of the distal portion 35a rests on the valve seat 46; and in the open position, the main shaft is raised and moves proximally against the bias of the conical spring 87 due to increased fuel pressure, and the tapered portion at the distal end of the main shaft 35 is not resting on the valve seat 46. When the main shaft 35 is raised in the open position, fuel can flow from the space surrounding the main shaft 35 to the nozzle orifice 45 located at the slightly distal end (distal end 44) ​​of the nozzle body 40. When the main shaft 35 is not raised, the main shaft 35 is in the closed position, and fuel from the space surrounding the main shaft 35 cannot flow to the nozzle orifice 45.

[0074] The proximal portion 35a and the distal portion 35b are configured to move concurrently between an open position and a closed position, while allowing the distal portion 35b to be radially displaced relative to the proximal portion 35a. This radial displacement capability of the distal portion 35b relative to the proximal portion 35a is limited to a very small distance to compensate for any slight misalignment between the nozzle body 40 and the elongated fuel valve body 32, which in practice is only a fraction of a millimeter. In this embodiment, these requirements are achieved by the distal end of the proximal portion 35a, which is configured to form a form-fit mechanical engagement with the proximal end of the distal portion 35b. In this invention, the distal portion of the proximal portion 35a is provided with a recess including a deep portion 63 wider than the shallow portion 61, which opens axially toward the distal end of the proximal portion 35a. The recess is configured to form a form-fit mechanical engagement with a protrusion formed at the proximal end of the distal portion 35b. The protrusion includes a head 64, which is wider than the neck 62 that supports the head 64. The diameters of the neck 62 and the head 64 are slightly smaller than the widths of the shallow portion 61 and the deep portion 63, respectively, thereby allowing the distal portion 35b to be displaced relative to the proximal portion 35 while forcing the proximal portion 35a and the distal portion 35b to move in unison in the axial direction. The axial extension of the head 64 is slightly smaller than the axial extension of the deep portion to ensure that there may be no play or only a very small play between the head 64 and the deep portion 63, thereby ensuring that the spindle 35 can move backward and forward in the axial direction, i.e., between a closed position and an open position, without noise or vibration caused by relative movement in the axial direction between the proximal portion 35a and the distal portion 35b.

[0075] The nozzle body 40 extends axially from a base 42 at the proximal end 41 of the nozzle body 40 to a distal end 44 of the nozzle body 40. The nozzle body 40 is releasably attached to an elongated fuel valve body 30, wherein the base 42 of the nozzle body 40 is connected to the distal end 33 of the valve body. A valve main bore 34 extends axially within the valve body 32 and opens to the distal end 33 of the valve body. A nozzle main bore 50 opens to the proximal end 41 of the nozzle body and extends axially from the proximal end 41 toward the distal end 44 of the nozzle body into the nozzle body 40, terminating in a valve seat 46 within the nozzle body 40. When the elongated valve member 35 is lifted from the valve seat 46, the nozzle main bore 50 is in fluid connection with a plurality of nozzle orifices 45, and when the elongated valve member 35 rests on the valve seat 45, the main bore 50 is fluidly disconnected from the plurality of nozzle orifices 45. The nozzle body 40 is provided with a circumferential flange, which is engaged by a sleeve 49 to secure the nozzle body 40 to the distal end of the valve body 32, i.e., to the spindle guide 89 forming the distal portion of the valve body 32. A nozzle main bore 50 opens to the proximal end 41 of the nozzle body and is in fluid communication with a valve main bore 34, which opens to the distal end 33 of the valve body, for receiving liquid fuel from the fuel valve 30. In this embodiment, the elongated valve member 35 moves against the bias of the elastic member 87 toward the proximal end 31 of the fuel valve 30 to achieve lifting. The lifting of the elongated valve member 35 is caused by the fuel pressure acting on the elongated valve member 35.

[0076] The proximal portion 35a is at least partially received in the valve main bore 34, and its axial movement is guided by the valve main bore 34. The distal portion 35b is at least partially received in the nozzle main bore 50, and its axial movement is preferably guided by the nozzle main bore 50. Because the distal portion 35b can be radially displaced relative to the proximal portion 35a, any slight misalignment between the nozzle main bore 50 and the valve main bore 34, for example after replacing a worn nozzle body 40, will not cause the spindle 35 to jam.

[0077] At the junction between the proximal portion 35a and the distal portion 35b, the proximal end of the distal portion 35b engages with the distal end of the proximal portion 35a. This junction allows radial displacement of the distal portion 35b relative to the proximal portion 35a. The axial position of the junction between the proximal and distal portions 35b is selected such that a majority of the length of the proximal portion 35a is received in the valve main bore 34, and a majority of the length of the distal portion 35b is received in the nozzle main bore 50.

[0078] In this embodiment, the joint includes a form-fit mechanical joint connection, which will be described in more detail below.

[0079] Figure 6The fuel valve 30 is shown with the nozzle body 40 removed. The second sleeve 49 has also been removed (unscrewed). In this embodiment, the distal portion 35b cannot be replaced without disassembling the spindle guide 89 because it requires lateral movement, i.e., radial movement, to slide the head 64 out of the deep recess 63, which is impossible when the proximal portion 35a is within the valve main bore 34. The spindle guide 89 can be removed (unscrewed) by removing (unscrewing) the first sleeve 88, and can be replaced if necessary, but this is much more difficult than removing (and replacing) the nozzle body 40.

[0080] Figures 11 to 13 , Figure 13A and Figure 13B Another embodiment of the fuel valve 30 is shown. Since the rest of the fuel valve is the same as in the embodiment described above, only the distal portions of the nozzle 40 and the valve needle 35 are shown in more detail. In this embodiment, for simplicity, structures and features that are the same as or similar to the corresponding structures and features described or shown above are indicated by the same reference numerals as previously used.

[0081] exist Figure 11 In the closed position, the spindle 35 is in the closed position, wherein the surface 36 of the distal end of the distal portion 35b rests on the valve seat 46, and... Figure 12 In the middle, the main shaft 35 has been lifted, that is, the surface 36 at the distal end of the distal portion 35b is not resting on the valve seat 46.

[0082] In this embodiment, the proximal portion 35 and the distal portion 35b are held together by hydraulic pressure, meaning that there is no form-fitting mechanical locking part, at least not only in the axial direction. Therefore, the joint between the proximal portion 35a and the distal portion 35b does not include a form-fitting mechanical locking part.

[0083] In order to make the proximal portion 35a and the distal portion 35b move in the same direction in the axial direction, the force generated by the hydraulic pressure acting on the distal portion 35b in the proximal direction is greater than the force generated by the hydraulic pressure acting on the distal portion 35b in the distal direction.

[0084] This is achieved by the following: a first abutting surface 75 is provided at the distal end of the proximal portion 35a, the first abutting surface 75 facing a second abutting surface 76 provided at the proximal end of the distal portion 35b (in Figure 13A(See detailed diagram). The first abutment surface 75 abuts against the second abutment surface (76). Fuel pressure acts on the distal portion 35b, pushing the distal portion 35b toward the proximal portion 35a, thereby pressing the second abutment surface 76 against the first abutment surface 75. The first abutment surface 75 and the second abutment surface 76 are complementary in shape to prevent fuel from flowing between the two surfaces when they abut against each other; that is, the two surfaces form a fluid seal. The proximal portion is provided with a conduit 71 that releases pressure from a portion of the first abutment surface 75 to reduce the force generated by the hydraulic pressure in the distal direction. Therefore, the hydraulic pressure acting on the distal portion 35b presses the distal portion 35b toward the proximal portion 35a. The distal end of the proximal portion 35a is provided with an orifice 77, in which the proximal end of the distal portion 35b is received with a clearance, allowing radial movement of the distal portion 35b relative to the proximal portion 35a to avoid requiring the valve main bore 36 to be perfectly aligned with the nozzle body main bore 50. The pressure in the conduit 71 is higher than the pressure at the proximal end of the proximal portion 35a, therefore the conduit 71 can be used as a seal for any fuel that may leak into the clearance between the valve main bore 34 and the proximal portion 35a.

[0085] The advantage of this implementation is that when the nozzle body 40 is removed, the distal portion 35b can be easily pulled out from its engagement with the proximal portion 35a. Therefore, the distal portion 35b can be replaced without removing the spindle guide 89, i.e., the nozzle body 40, thus providing greater flexibility and maintainability.

[0086] Figure 13 The fuel valve shown is equipped with a replaceable heat barrier 93 to protect the nozzle body 40 from the thermal circulation within the combustion chamber 14, thereby reducing thermal stress and thermal circulation on the nozzle body 40 and extending its service life. The heat barrier 93 can be applied to any of the embodiments shown.

[0087] According to this embodiment, such as Figure 13A and Figure 13B As best shown, another feature of the fuel valve 30 is a spare valve seat 96, which is configured to operate together with a spare sealing surface 97. The spare valve seat 96 is located in the elongated valve body 32 (in this embodiment, in the spindle guide 89), and the spare sealing surface 97 is formed on the proximal portion 35a. When the elongated valve member (35) is in the open position, closed position (e.g., Figure 13 , Figure 13A and Figure 13BWhen the valve member 35 is positioned either in the open or closed position, or in any position between the open and closed positions, the backup valve seat 96 and the backup sealing surface (97) are positioned with the backup valve seat 96 raised. The backup sealing surface 97 rests on the backup valve seat 96 when the elongated valve member 35 is positioned further away from the position where the distal end of the distal portion 35b rests on the valve seat 46. This typically only occurs when the nozzle body 40 is damaged, resulting in the valve seat 46 disappearing and no longer preventing movement of the valve spindle 35 in the distal direction. Without the backup valve seat 96, this situation would result in uninterrupted and uncontrolled fuel flow into the combustion chamber 14, a highly undesirable situation due to the risk of a large amount of fuel accumulating in the combustion chamber, which could lead to a fuel ejection event, further damaging the engine and potentially injuring personnel near the engine. Having the backup valve seat 96 mitigates these risks in the event of nozzle body 40 damage, i.e., separation of the distal portion of the nozzle body 40 from the proximal portion.

[0088] Various aspects and implementations have been described in conjunction with various embodiments herein. However, by studying the accompanying drawings, this disclosure, and the appended claims, those skilled in the art who practice the claimed subject matter will understand and implement other variations of the disclosed embodiments. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "the" do not exclude multiple.

[0089] The reference numerals used in the claims shall not be construed as limiting the scope. Unless otherwise stated, the drawings will be read in conjunction with the description (e.g., crosshairs, arrangement of parts, scale, extent, etc.) and will be considered part of the entire written description of this disclosure. As used in the description, the terms “horizontal,” “vertical,” “left,” “right,” “up,” and “down,” and their adjective and adverbial derivatives (such as “horizontally,” “to the right,” “upward,” etc.) refer only to the orientation of the illustrated structure when the particular drawing is facing the reader. Similarly, the terms “inward” and “outward” generally refer, as appropriate, to the orientation of a surface relative to its axis of extension or axis of rotation.

Claims

1. A fuel valve (30) for injecting liquid fuel into the combustion chamber of a large two-stroke turbocharged single-flow scavenging internal combustion engine having a crosshead, the fuel valve (30) comprising: - An elongated fuel valve body (32) extending axially between a proximal end (31) and a distal end (33) of the fuel valve body. - Nozzle body (40), the nozzle body (40) extending axially from a base (42) located at the proximal end (41) of the nozzle body (40) to the distal end (44) of the nozzle body (40), The nozzle body (40) is releasably attached to the fuel valve body (32), and the base (42) is connected to the distal end (33) of the valve body. - Valve main bore (34), which extends axially in the fuel valve body (32) and leads to the distal end (33) of the fuel valve body. - A nozzle main bore (50) leading to a distal end (41) of the nozzle, and the nozzle main bore (50) extending axially from the proximal end (41) of the nozzle toward the distal end (44) of the nozzle into the nozzle body (40) and terminating in a valve seat (46) within the nozzle body (40). - An elongated valve component (35) capable of axially shifting between a closed position and an open position, wherein in the closed position the elongated valve component (35) rests on the valve seat (46), and in the open position the elongated valve component (35) is lifted off the valve seat (46). - When the elongated valve member (35) is lifted from the valve seat (46), the main nozzle orifice (50) is fluidly connected to the plurality of nozzle orifices (45), and when the elongated valve member (35) rests on the valve seat (46), the main nozzle orifice (50) is fluidly disconnected from the plurality of nozzle orifices (45), and - The elongated valve member (35) includes a proximal portion (35a) and a distal portion (35b), the distal portion (35b) being configured to move axially between the closed position and the open position in accordance with the proximal portion (35a), characterized in that the distal portion (35b) is configured to be radially displaced relative to the proximal portion (35a).

2. The fuel valve (30) according to claim 1, wherein: - The proximal portion (35a) is at least partially received in the valve main bore (34), preferably, the axial movement of the proximal portion is guided by the valve main bore (34), and -in, The distal portion (35b) is at least partially received in the nozzle main bore (50), and preferably, the axial movement of the distal portion (35b) is guided by the nozzle main bore (50).

3. The fuel valve (30) according to claim 1 or 2, wherein, At the junction between the proximal portion (35a) and the distal portion (35b), the proximal end of the distal portion (35b) engages with the distal end of the proximal portion (35a), the junction allowing the distal portion (35b) to be radially displaced relative to the proximal portion (35a).

4. The fuel valve (30) according to any one of claims 1 to 3, wherein, The joint includes a form-fit mechanical joint connection.

5. The fuel valve (30) according to claim 4, wherein, The form-fitting mechanical joint connection includes recesses (61, 63) and protrusions (62, 64) received in the recesses (61, 63). Preferably, the recesses include a deep portion (63) that is wider than the shallow portion (61), and the protrusions include a head (64) that is wider than the neck (62) that supports the head (64).

6. The fuel valve (30) according to claim 4 or 5, wherein, The proximal end of the distal portion (35b) together with the distal end of the proximal portion (35a) forms a form-fit mechanical joint connection.

7. The fuel valve (30) according to any one of claims 4 to 6, wherein, The distal portion (35b) is releasably connected to the proximal portion (35b) via the form-fitting mechanical joint connector.

8. The fuel valve (30) according to any one of claims 1 to 3, wherein, The distal end of the proximal portion (35a) includes a first abutting surface (75), and the proximal end of the distal portion (35b) includes a second abutting surface (76), and the first abutting surface (75) abuts against the second abutting surface (76). Preferably, the first abutting surface (75) and the second abutting surface (76) abut against each other by fuel pressure acting on the distal portion (35b), the fuel pressure pushing the distal portion (35b) toward the proximal portion (35a), thereby pressing the second abutting surface (76) against the first abutting surface (75).

9. The fuel valve (30) according to claim 8, wherein, The first abutting surface (75) abuts against the second abutting surface (76) to form a fluid seal.

10. The fuel valve (30) according to claim 8 or 9, wherein, The distal end of the proximal portion (35a) is provided with a hole (77), and the proximal end of the distal portion (35b) is received in the hole (77) with a clearance, thereby allowing the distal portion (35b) to move radially relative to the proximal portion (35a).

11. The fuel valve (30) according to any one of claims 1 to 10, wherein, The fuel valve body (32) includes a distal portion (89) that is releasably attached to the remainder of the fuel valve body (32). Preferably, the distal portion (89) is releasably attached to the remainder of the fuel valve body (32) via a first sleeve (88) that is threadedly engaged with the remainder of the fuel valve body (32).

12. The fuel valve (30) according to any one of claims 1 to 11, wherein, The nozzle (40) is releasably attached to the fuel valve body (32) via a second sleeve (49), which is threadedly engaged with the fuel valve body (32).

13. The fuel valve (30) according to any one of claims 1 to 12, wherein, The distal portion (35b) has a distal end (36) that rests on the valve seat (46) when the elongated valve member (35) is in the closed position. Preferably, the distal end (36) of the distal portion (35b) has a shape complementary to the shape of the valve seat, such that no fuel can flow through the valve seat (46) when the elongated valve member (35) is in the closed position.

14. The fuel valve (30) according to any one of claims 1 to 13, wherein, The nozzle main orifice (50) leads to the proximal end (41) of the nozzle and is fluidly connected to the valve main orifice (34) leading to the distal end (33) of the fuel valve body for receiving liquid fuel from the fuel valve (30).

15. The fuel valve (30) according to any one of claims 1 to 14, wherein, The elongated valve member (35) moves toward the proximal end (31) of the fuel valve (30) to achieve lifting. Preferably, the elongated valve member (35) moves toward the proximal end (31) of the fuel valve (30) against the bias of the elastic member (87) to achieve lifting.

16. The fuel valve (30) according to any one of claims 1 to 15, wherein, The lifting of the elongated valve component (35) is caused by the fuel pressure acting on the elongated valve component (35).

17. The fuel valve (30) according to any one of claims 1 to 16, wherein, The fuel chamber (68) surrounds the distal end of the proximal portion (35a).

18. The fuel valve (30) according to any one of claims 1 to 17, the fuel valve (30) comprising a spare valve seat (96) configured to operate together with a spare sealing surface (97), the spare valve seat (96) being disposed in the fuel valve body (32), and the spare sealing surface (97) being formed on the proximal portion (35a), wherein the spare valve seat (96) and the spare sealing surface (97) are configured to be raised when the elongated valve member (35) is in the open position, the closed position, or any position between the open position and the closed position, and wherein, When the elongated valve member (35) is positioned further away from the position where the distal end of the distal portion (35b) rests on the valve seat (46), the spare sealing surface (97) rests on the spare valve seat (96).

19. A large two-stroke turbocharged single-flow scavenging internal combustion engine with a crosshead, comprising a fuel valve (30) according to any one of claims 1 to 18.

Images