Marine methanol engine fuel leakage monitoring device
By installing a transparent observation window and a methanol concentration sensor in the methanol engine fuel delivery pipeline, combined with a PLC controller, rapid location and cut-off of methanol fuel leaks can be achieved, solving the problem that existing technologies cannot detect minor leaks in a timely manner, and improving the safety and maintenance efficiency of marine methanol engines.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CSSC MARINE POWER
- Filing Date
- 2025-08-06
- Publication Date
- 2026-06-26
AI Technical Summary
Existing technologies cannot quickly and accurately detect minor leaks in marine methanol engine fuel delivery pipelines, especially when the leak amount is below 500 ppm, which poses a safety hazard.
The system employs a structure consisting of a connecting channel block, a two-way solenoid valve, a transparent observation window, a methanol concentration sensor, and a vent plug. It is fixedly connected via a methanol double-wall common rail pipe, and equipped with a transparent observation window and a methanol concentration sensor. Combined with a PLC controller, it enables real-time monitoring and rapid location of methanol fuel leaks.
It can issue an alarm signal when methanol fuel leakage reaches 2000ppm and quickly cut off the fuel supply to the leak point, ensuring safe and reliable engine operation and improving maintenance efficiency and safety.
Smart Images
Figure CN224413779U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a safety device for a new energy engine, and more particularly to a fuel leakage monitoring device for a marine methanol fuel or methanol dual-fuel engine, belonging to the field of new energy engine technology. Background Technology
[0002] Methanol fuel, as a low-carbon fuel, is increasingly widely used and has begun to be applied in small batches to marine engines. Currently, most marine methanol engines use an inner pipe to transport methanol fuel, with an annular cavity between the inner and outer pipes maintaining ventilation and permeability in a methanol double-walled common rail system. An additional ventilated purging device ensures the safety of the marine methanol engine in the event of a methanol fuel leak. For example, application publication number CN117365773A discloses a method and device for protecting methanol engine fuel leaks. This method involves installing a leak return pipe on one side of the methanol nozzle valve seat, which is connected to a liquid methanol leak detection unit. Leaking liquid methanol flows back along the leak return pipe under gravity into the liquid methanol leak detection unit below, triggering an alarm and being collected by a collection device at the end. However, this device can only detect methanol fuel leaks at the methanol nozzle valve seat and cannot detect which cylinder on the marine methanol engine body is leaking, or which section of the methanol common rail is leaking. Especially when there is a minor leak of less than 500 ppm, users may not be able to detect it in time, and it is difficult to quickly find the leak point, which poses a certain degree of safety hazard. Utility Model Content
[0003] The purpose of this invention is to provide a fuel leak monitoring device for marine methanol engines that can quickly and accurately locate leak points, thereby ensuring the safe and reliable operation of marine methanol engines.
[0004] This utility model is achieved through the following technical solution:
[0005] The objective of this utility model can also be achieved in one step through the following technical measures.
[0006] A fuel leak monitoring device for a marine methanol engine includes a connecting channel block, a two-way solenoid valve, a transparent observation window, a methanol concentration sensor, and a drain plug. Several spaced-apart connecting channel blocks are fixedly connected by methanol double-walled common rail pipes. Connecting flanges at both ends of the methanol double-walled common rail pipe connecting two connecting channel blocks are respectively embedded and fixed in the flange countersunk holes at the left and right ends of the connecting channel block. The connecting holes of the connecting channel blocks are connected to the inner tube of the methanol double-walled common rail pipe through corresponding flange countersunk holes. Several outer tube through holes with axes parallel to the axis of the connecting hole are spaced apart on the upper and lower sides of the through hole. The two ends of these outer tube through holes are connected to the annular cavity between the inner and outer tubes of the methanol double-walled common rail pipe through multiple outer tube connection holes around the connecting flange. One end of a methanol supply pipe is connected to the inner tube of the methanol double-walled common rail pipe between two adjacent cylinders, and the other end of the methanol supply pipe is connected to the methanol injector of the corresponding cylinder. Two power supplies are provided. The solenoid valve body is embedded in the large end countersunk hole of the stepped countersunk hole on the rear side of the connecting channel block. The valve core extending from the body of the two-way solenoid valve is embedded in the small end countersunk hole of the stepped countersunk hole, which intersects perpendicularly with the connecting hole. An observation window countersunk hole is provided at the center of the front end of the connecting channel block. The transparent observation window is fixed to the outside of the observation window countersunk hole by interference fit. The axes of the detection channel holes symmetrically arranged on the upper and lower sides of the observation window countersunk hole are parallel to the axis of the stepped countersunk hole. One end of the detection channel hole communicates with the bottom surface of the observation window countersunk hole, and the other end of the detection channel hole intersects perpendicularly with the corresponding external tube through holes. The lower end of the methanol concentration sensor is fixed in the upper end of the sensor screw hole, which is located on the upper side of the observation window countersunk hole and intersects perpendicularly with the observation window countersunk hole. The upper end of the vent plug is fixed in the lower end of the vent screw hole, which is located on the lower side of the observation window countersunk hole. The signal lines of the PLC controller are connected to the electromagnets of each two-way solenoid valve, and the signal lines are also connected to the control terminals of each methanol concentration sensor.
[0007] Furthermore, the two-way solenoid valve is a normally open type. The valve core of the normally open type two-way solenoid valve is clearance-fitted with the countersunk hole at the small end, and several O-rings are installed on the valve core. A transverse hole is provided in the middle of the valve core. When the electromagnet of the two-way solenoid valve is not energized, the valve core moves outward into position under the action of the compression spring in the valve body of the two-way solenoid valve, and the transverse hole communicates with the connecting hole. When the electromagnet of the two-way solenoid valve is energized, the electromagnet pulls the valve core inward into position against the elastic force of the compression spring, and the transverse hole is not connected to the connecting hole, thus cutting off the inner pipe channel of the methanol double-wall common rail pipe.
[0008] Furthermore, the two-way solenoid valve core has an axial blind hole at the end facing the observation window countersunk hole.
[0009] Furthermore, the ratio of the diameter of the transverse hole D1 to the diameter of the connecting hole D2 is: D1 / D2 = 0.70 to 0.76.
[0010] Furthermore, the transparent observation window is made of resin.
[0011] Furthermore, the methanol concentration sensor has a measurement range of 0–20000 ppm and outputs a current signal of 4–20 mA.
[0012] This invention employs a structure consisting of several spaced-apart connecting channel blocks, each fixedly connected by a methanol double-walled common rail. Two-way solenoid valves and methanol concentration sensors are mounted on these connecting channel blocks. The methanol supply pipes to each cylinder are connected to the inner tubes of the methanol double-walled common rail. When methanol fuel leaks from the inner tube of the methanol double-walled common rail near a cylinder into the annular cavity between the inner and outer tubes, the methanol detectors on all connecting channel blocks after that cylinder will detect the leak. When the methanol fuel leakage reaches the alarm threshold of 2000 ppm, the PLC controller receives a signal from the methanol concentration sensor indicating excessive methanol fuel leakage and issues an audible and visual alarm, displaying which methanol double-walled common rail is leaking, thus enabling timely and accurate location of the leak point. Simultaneously, the two-way solenoid valves on the connecting channel blocks after that cylinder retract their valve cores upon receiving a power command from the PLC controller, cutting off the inner tube channels of the corresponding methanol double-walled common rails, preventing further methanol fuel leakage, facilitating timely maintenance by the user, and significantly improving the safety of marine methanol engines during operation.
[0013] The advantages and features of this utility model will be illustrated and explained through the following non-limiting description of preferred embodiments, which are given by way of example only with reference to the accompanying drawings. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the structure of this utility model used in a marine methanol engine;
[0015] Figure 2 This is a full sectional view of the present invention, in which the transverse hole communicates with the connecting hole;
[0016] Figure 3 yes Figure 2 The AA section view shows that the transverse hole and the connecting hole are not connected at this time;
[0017] Figure 4 This is the left view of the connecting channel block;
[0018] Figure 5 yes Figure 4 BB cross-sectional view. Detailed Implementation
[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments of a marine 7-cylinder methanol engine.
[0020] In the description of this utility model, terms such as “center,” “upper,” “lower,” “left,” “right,” “inner,” and “outer” that indicate orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and do not indicate or imply that the device referred to must have a specific orientation.
[0021] like Figures 1-5 As shown, this embodiment includes a connecting channel block 1, a two-way solenoid valve 2, a transparent observation window 3, a methanol concentration sensor 4, and a vent plug 5. The six spaced-apart connecting channel blocks 1 are connected by methanol double-wall common rail pipes 6. Figure 2 As shown, the connecting flanges 61 at both ends of the methanol double-wall common rail pipe 6 used to connect the two connecting channel blocks 1 are respectively embedded in the flange connecting countersunk holes 11 at the left end and the right end of the connecting channel block 1. The two ends of the connecting hole 12 of the connecting channel block 1 are connected to the inner pipe 62 of the methanol double-wall common rail pipe 6 through the corresponding flange connecting countersunk holes 11. Figure 3 and Figure 5 As shown, three external tube through holes 13 with their axes parallel to the axis of the connecting hole 12 are respectively provided on the upper and lower sides of the connecting hole 12. The two ends of the six external tube through holes 13 are connected to the annular cavity 63 between the inner and outer tubes of the methanol double-wall common rail pipe 6 through a ring of external tube connecting holes 621 of the connecting flange 62. When the marine methanol engine is working, the inner tube 61 of the methanol double-wall common rail pipe 6 is filled with methanol fuel with a pressure greater than 10 bar. The annular cavity 63 between the inner and outer tubes of the methanol double-wall common rail pipe 6 is kept in a ventilated state, maintaining a ventilated pressure of 200~500 mbar.
[0022] like Figures 1-3 As shown, one end of the methanol supply pipe 7 is connected to the inner pipe 61 of the methanol double-wall common rail pipe 6 between two adjacent cylinders 10, and the other end of the methanol supply pipe 7 is connected to the methanol injector of the corresponding cylinder 10. The valve body 21 of the two-way solenoid valve is embedded in the large end countersunk hole 141 of the stepped countersunk hole 14 on the rear side of the connecting channel block 1, and the valve core 22 extending from the valve body 21 is embedded in the small end countersunk hole 142 of the stepped countersunk hole. The small end countersunk hole 142 intersects the connecting hole 12 perpendicularly.
[0023] like Figures 3-5As shown, the front end of the connecting channel block 1 has an observation window countersunk hole 15. A transparent resin observation window 3 is fixed to the outside of the observation window countersunk hole 15 by an interference fit. When a section of the methanol double-wall common rail pipe 6 has a large amount of methanol fuel leakage from the inner pipe 61, the leakage from the inner pipe 61 into the annular cavity 63 of the inner and outer pipes can be directly seen through the transparent observation window 3. The methanol fuel then flows into the observation window countersunk hole 15 through the detection channel hole 16. This allows for accurate identification of which section of the methanol double-wall common rail pipe 6 is leaking, facilitating the immediate replacement of that section of the methanol double-wall common rail pipe 6, reducing methanol fuel leakage, improving the maintenance efficiency of marine methanol engines, and ensuring the safe operation of marine methanol engines.
[0024] like Figure 5 As shown, the axes of the detection channel holes 16, which are symmetrically arranged on the upper and lower sides of the observation window countersunk hole 15, are parallel to the axis of the stepped countersunk hole 14. One end of the detection channel hole 16 is connected to the bottom surface of the observation window countersunk hole 15, and the other end of the detection channel hole 16 is perpendicular to the three corresponding external tube through holes 13.
[0025] like Figure 3 As shown, the lower end of the methanol concentration sensor 4 is fixed in the upper end of the sensor screw hole 151, which is located above the observation window countersunk hole 15 and perpendicularly intersects it. The upper end of the vent plug 5 is fixed in the lower end of the vent screw hole 152, which is located below the observation window countersunk hole 15. When methanol fuel leaks from the inner tube 61 of a section of the methanol double-wall common rail pipe 6, the leaked methanol fuel flows sequentially into the observation window countersunk hole 15 through the annular cavity 63 of the inner and outer tubes of the double-wall common rail pipe 6, the outer tube through-hole 13, and the detection channel hole 16. When the volume of methanol fuel in the observation window countersunk hole 15 is visually observed through the transparent observation window 3, the vent plug 5 can be opened to release the methanol fuel in the observation window countersunk hole 15 into a specific container.
[0026] like Figure 1 As shown, the signal line 81 of the PLC controller 8 is connected to the electromagnet of each two-way solenoid valve 2, and the signal line 81 is also connected to the control terminal of each methanol concentration sensor 4.
[0027] like Figure 2 and Figure 3As shown, the two-way solenoid valve 2 is a normally open type. The valve core 22 of the two-way solenoid valve 2 is clearance-fitted with the small end countersunk hole 142, and the valve core 22 is equipped with three O-ring seals 23. A transverse hole 221 is provided in the middle of the valve core 22. When the electromagnet of the two-way solenoid valve 2 is not energized, under the action of the compression spring in the valve body 21, the valve core 22 moves in and out of the small end countersunk hole 142, and the transverse hole 221 communicates with the connecting hole 12 of the connecting channel block 1. Methanol fuel passes sequentially through the connecting hole 12 of the connecting channel block 1, the inner tube 61 of the corresponding methanol double-wall common rail pipe 6, and the methanol supply pipe 7, leading to the methanol injector of the corresponding cylinder 10. When the electromagnet of the two-way solenoid valve 2 is energized, the electromagnet pulls the valve core 22 inward against the elastic force of the compression spring, and the transverse hole 221 is not connected to the connecting hole 12, cutting off the passage of the inner tube 61 of the methanol double-wall common rail pipe 6.
[0028] The valve core 22 is provided with an axial blind hole 222 at the end facing the observation window countersunk hole 15. Its function is to collect the small amount of leaked methanol fuel when a small amount of methanol fuel leaks from the connecting hole 12 into the small end countersunk hole 142. It can also lubricate the valve core 22 and the small end countersunk hole 142 to prevent the valve core 22 from being unable to move out and extend into place.
[0029] like Figure 2 and Figure 4 As shown, in this embodiment, the ratio of the diameter of the transverse hole D1 to the diameter of the connecting hole D2 is D1 / D2 = 0.73. Since the diameter of the transverse hole 221 is less than 3 / 4 of the diameter of the connecting hole 12, the sealing performance of the connection between the transverse hole 221 and the connecting hole 12 is effectively improved.
[0030] The methanol concentration sensor 4 has a measurement range of 0–20000 ppm and outputs a current signal of 4–20 mA.
[0031] The working process of this utility model is as follows:
[0032] When there is no leakage in the methanol double-wall common rail 6 leading to each cylinder 10, methanol fuel is normally delivered to the methanol injector of the corresponding cylinder 10 through the methanol supply pipe 7 connected to the methanol double-wall common rail 6. Each methanol injector injects methanol fuel into the corresponding cylinder 10 for ignition and power generation, and the marine methanol engine operates normally.
[0033] If a leak occurs in the methanol double-wall common rail pipe 6 leading to cylinder #3 (10), methanol fuel will leak from the inner pipe 61 of the methanol double-wall common rail pipe 6 into the annular cavity 63 between the inner and outer pipes, and then sequentially through the annular cavity 63, the six outer pipe through holes 13, and the detection channel hole 16 into the observation window countersunk hole 15, causing the methanol fuel to leak from cylinder #3 (10). The methanol detectors 4 on each subsequent connecting channel block 1 detected methanol fuel leakage. When the methanol fuel leakage reached the alarm threshold of 2000 ppm, the methanol detector 4 sent a signal to the PLC controller 8, which issued an audible and visual alarm signal. At the same time, the two-way solenoid valve 2 on the connecting channel block 1 corresponding to cylinder #3 10 received the signal from the PLC controller 8 and was energized. The electromagnet generated electromagnetic attraction, and the valve core 22 retracted into the valve body 21 after being attracted by the electromagnetic force, cutting off the connection between the transverse hole 221 of the valve core 22 and the connecting hole 12 on the connecting channel block 1, thereby cutting off the inner pipe 61 channel of the methanol double-wall common rail pipe 6 in that section. Although Figure 1 The methanol detectors 4 on each connecting channel block 1 on the right side of cylinder #3 10 all received methanol fuel leakage signals. However, since the methanol double-wall common rail pipe 6 connected to cylinder #3 10 has the largest leakage, the PLC controller 8 can determine and display that the methanol double-wall common rail pipe 6 has a leakage after logical judgment. This allows the leak point to be found in a timely, fast, effective and reliable manner, which is convenient for users to carry out timely maintenance and ensure the safety of marine methanol engines.
[0034] In addition to the above embodiments, the present invention may have other implementation methods. All technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope claimed by the present invention.
Claims
1. A fuel leak monitoring device for marine methanol engines, characterized in that, The system includes a connecting channel block, a two-way solenoid valve, a transparent observation window, a methanol concentration sensor, and a vent plug. Several connecting channel blocks are spaced apart and connected by methanol double-wall common rail pipes. Connecting flanges at both ends of the methanol double-wall common rail pipe connecting two connecting channel blocks are embedded and fixed in the flange countersunk holes at the left and right ends of the connecting channel block, respectively. The two ends of the connecting hole are connected to the inner tube of the methanol double-wall common rail pipe through corresponding flange countersunk holes. Several outer tube through holes with axes parallel to the axis of the connecting hole are spaced apart on the upper and lower sides of the connecting hole. The two ends of these outer tube through holes are connected to the annular cavity between the inner and outer tubes of the methanol double-wall common rail pipe through multiple outer tube connecting holes around the connecting flange. One end of the methanol supply pipe is connected to the inner tube of the methanol double-wall common rail pipe between two adjacent cylinders, and the other end of the methanol supply pipe is connected to the methanol injector of the corresponding cylinder. The valve body of the two-way solenoid valve is embedded and fixed in the connecting channel block. In the large countersunk hole of the stepped countersunk hole on the rear side of the guide block, the valve core extending from the valve body of the two-way solenoid valve is embedded in the small countersunk hole of the stepped countersunk hole, and the small countersunk hole intersects perpendicularly with the connecting hole; the front center of the connecting channel block is provided with an observation window countersunk hole, and the transparent observation window is fixed to the outside of the observation window countersunk hole by interference fit; the axis of the detection channel hole symmetrically arranged on the upper and lower sides of the observation window countersunk hole is parallel to the axis of the stepped countersunk hole, one end of the detection channel hole is connected to the bottom surface of the observation window countersunk hole, and the other end of the detection channel hole is perpendicularly intersected with the corresponding external tube through holes; the lower end of the methanol concentration sensor is fixed in the upper end of the sensor screw hole, and the sensor screw hole is located on the upper side of the observation window countersunk hole and intersects perpendicularly with the observation window countersunk hole; the upper end of the vent plug is fixed in the lower end of the vent screw hole, and the vent screw hole is located on the lower side of the observation window countersunk hole; the signal lines of the PLC controller are respectively connected to the electromagnets of each two-way solenoid valve, and the signal lines are also respectively connected to the control terminals of each methanol concentration sensor.
2. The marine methanol engine fuel leakage monitoring device as described in claim 1, characterized in that, The two-way solenoid valve is a normally open type. The valve core is clearance-fitted with the small end countersunk hole, and the valve core is equipped with several O-ring seals. A transverse hole is provided in the middle of the valve core. When the electromagnet of the two-way solenoid valve is not energized, the valve core in the small end countersunk hole moves outward under the action of the compression spring in the valve body, and the transverse hole communicates with the connecting hole. When the electromagnet of the two-way solenoid valve is energized, the electromagnet pulls the valve core to move inward against the elastic force of the compression spring, and the transverse hole is not connected to the connecting hole, thus cutting off the inner pipe channel of the methanol double-wall common rail pipe.
3. The marine methanol engine fuel leakage monitoring device as described in claim 1, characterized in that, An axial blind hole is provided at the end of the valve core facing the observation window countersunk hole.
4. The marine methanol engine fuel leakage monitoring device as described in claim 1, characterized in that, The ratio of the diameter of the horizontal hole D1 to the diameter of the connecting hole D2 is: D1 / D2 = 0.70 to 0.
76.
5. The marine methanol engine fuel leakage monitoring device as described in claim 1, characterized in that, The transparent observation window is made of resin.
6. The marine methanol engine fuel leakage monitoring device as described in claim 1, characterized in that, The methanol concentration sensor has a measurement range of 0–20000 ppm and outputs a current signal of 4–20 mA.