Marine low-speed diesel engine methanol injection system with airtightness detection function

Abstract

The utility model discloses a marine low-speed diesel engine methanol injection system with an airtight detection function, which is formed by communicating a methanol liquid inlet double-wall pipe, a methanol liquid return double-wall pipe, a methanol pressurizing unit and a high-pressure pipeline, and the methanol liquid inlet double-wall pipe is communicated with a fresh water supply system through a liquid inlet stop valve. A liquid return stop valve is arranged on the methanol liquid return double-wall pipe, a liquid return chain pipe valve is communicated between the methanol liquid return double-wall pipe and the methanol pressurizing unit, and a communication valve is arranged between the methanol liquid inlet double-wall pipe and the methanol liquid return double-wall pipe; a communicating port of the high-pressure pipeline and the methanol pressurizing unit is plugged through a plugging tool which is detachably arranged on the methanol pressurizing unit, and a plurality of methanol pressure detection sensors are arranged on the methanol liquid inlet double-wall pipe and the methanol liquid return double-wall pipe respectively. According to the utility model, fresh water with intersolubility with methanol is used as a tightness inspection medium, so that the complete tightness inspection of the methanol spraying system of the marine methanol dual-fuel low-speed diesel engine is realized, the detection efficiency is high, and the leakage point detection speed is high.

Description

TECHNICAL FIELD

[0001] The utility model relates to a marine low -speed diesel engine methanol injection system with air -tight detection function belongs to marine diesel engine technical field. BACKGROUND

[0002] In the field of ship transportation, the regulatory limit value requirement of the emission of the internal combustion engine can be increasingly strict, and the attention degree of the internal combustion engine alternative fuel is increasingly improved at home and abroad. Methanol fuel has been confirmed as a kind of clean fuel, does not contain sulfur, and only contains very few particles, and the emission of NOx, SOx and particles is lower than that of traditional diesel engine, which meets the emission requirement of the International Maritime Organization. The marine methanol diesel engine learns from the mature diesel engine technology, only needs to make small improvement to the original diesel engine, and the technology is relatively mature, and the cost is relatively low, and in recent years, the shipping industry in the world has paid attention.

[0003] Methanol is fused with water, when methanol is exposed to air, it will absorb water in the air, and the methanol containing water is more corrosive. Compared with conventional diesel fuel, methanol fuel has a higher risk coefficient, once leakage occurs, the possibility of causing engine room fire and crew casualties is higher, which will have very serious consequences on the safety of ships and crew. Therefore, it is essential to check the sealing of the methanol injection system. And the traditional dual-fuel main engine adopts nitrogen for conventional air tightness inspection, and it is found through test that the air tightness inspection efficiency of nitrogen on the methanol engine is not ideal, and it is difficult to quickly find the leakage point, therefore, the diesel engine methanol injection system in the field urgently needs an air tightness structure that can quickly realize the air tightness inspection of the methanol diesel engine. UTILITY MODEL CONTENTS

[0004] The technical problem to be solved by the utility model is that the sealing inspection method used by the existing methanol diesel engine has low inspection efficiency and cannot quickly find the leakage point.

[0005] In order to solve the above technical problem, the utility model provides a marine low-speed diesel engine methanol injection system with air tightness detection function, uses fresh water with mutual solubility with methanol as the air tightness inspection medium, and realizes complete air tightness inspection of the marine methanol dual-fuel low-speed diesel engine methanol injection system.

[0006] In order to realize the above technical purpose and achieve the above technical effect, the utility model realizes the following technical scheme:

[0007] The utility model provides a kind of with air-tightness detection function's marine low-speed diesel engine methanol injection system, including methanol injection system, the methanol injection system includes methanol inlet double-wall pipe, methanol return liquid double-wall pipe, methanol booster unit and high pressure pipeline, inlet stop valve is equipped on the methanol inlet double-wall pipe, return liquid stop valve is equipped on the methanol return liquid double-wall pipe, methanol inlet double-wall pipe and methanol return liquid double-wall pipe are communicated with the methanol booster unit, and return liquid chain pipe valve is communicated between methanol return liquid double-wall pipe and the methanol booster unit, communication valve is arranged between methanol inlet double-wall pipe and methanol return liquid double-wall pipe, one end of the high pressure pipeline is detachably communicated with the methanol booster unit, and the other end corresponds to communicate multiple alcohol sprayers;

[0008] It further includes fresh water supply system, plugging tool and methanol pressure detection sensor, the fresh water supply system is communicated with the methanol inlet double-wall pipe by the inlet stop valve, the plugging tool is detachably arranged on methanol booster unit to block the communication port of high pressure pipeline and methanol booster unit, the methanol pressure detection sensor is provided with multiple and is divided and arranged on methanol inlet double-wall pipe and methanol return liquid double-wall pipe, and multiple methanol pressure detection sensors are connected with external host control detection system.

[0009] Preferably, the high pressure pipeline includes at least three methanol high pressure pipes communicated with the methanol booster unit, the methanol high pressure pipe is a double-wall pipe, and the methanol booster unit is provided with a plurality of double-wall pipe connection ports corresponding to the socket communication of the methanol high pressure pipe.

[0010] Further, the plugging tool includes a sealing column, a sealing cover and fastening bolts, the sealing column is inserted into the double-wall pipe connection port to achieve plugging, and the fastening bolts are provided with multiple and are screwed with the outer wall of the methanol booster unit through the sealing cover.

[0011] Further, the outer wall of one end of the sealing column inserted into the double-wall pipe connection port is provided with a conical surface.

[0012] Further, the sealing column is provided in a cylindrical shape, and the sealing cover is a circular cover plate and is coaxially arranged with the sealing column.

[0013] Further, multiple fastening bolts are uniformly arranged around the circumferential direction of the sealing cover.

[0014] Further, the alcohol sprayer is provided with multiple corresponding to the methanol high pressure pipe.

[0015] Preferably, the inlet stop valve is arranged at the inlet port of the methanol inlet double-wall pipe, and the return liquid stop valve is arranged at the return liquid port of the methanol return liquid double-wall pipe.

[0016] Further, the methanol pressure detection sensor is provided with three and respectively arranged before the methanol pressurizing unit inlet, after the liquid inlet cut-off valve and before the liquid return cut-off valve.

[0017] Preferably, the fresh water supply system comprises a fresh water supply pump.

[0018] The methanol injection system for marine low-speed diesel engine with air tightness detection function has the following advantages.

[0019] The methanol injection system for marine low-speed diesel engine with air tightness detection function provided by the utility model has the following advantages. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The structure schematic view of the methanol injection system for marine low-speed diesel engine with air tightness detection function provided by the utility model embodiment is shown in the figure.

[0021] Figure 2 The structure schematic view of the methanol injection system for marine low-speed diesel engine with air tightness detection function provided by the utility model embodiment is shown in the figure.

[0022] Figure 3 The structure schematic view of the methanol injection system for marine low-speed diesel engine with air tightness detection function provided by the utility model embodiment is shown in the figure.

[0023] Figure 4 The structure schematic view of the plugging tool provided by the utility model embodiment is shown in the figure.

[0024] In the figure:

[0025] 1-methanol liquid inlet double-wall pipe; 2-methanol liquid return double-wall pipe; 3-methanol pressurizing unit; 31-double-wall pipe connecting port; 4-high pressure pipeline; 41-methanol high pressure pipe; 5-liquid inlet cut-off valve; 6-liquid return cut-off valve; 7-liquid return chain pipe valve; 8-communication valve; 9-methanol injector; 10-plugging tool; 101-plugging column; 102-plugging cover; 103-fastening bolt; 11-methanol pressure detection sensor. DETAILED DESCRIPTION

[0026] Clearly, the described embodiments are merely a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0027] With reference to Figures 1-4 The application provides a marine low-speed diesel engine methanol injection system with air tightness detection function, which comprises a methanol injection system, the methanol injection system comprises a methanol liquid inlet double-wall pipe 1, a methanol liquid return double-wall pipe 2, a methanol supercharging unit 3 and a high-pressure pipeline 4, a liquid inlet stop valve 5 is installed on the methanol liquid inlet double-wall pipe 1, a liquid return stop valve 6 is installed on the methanol liquid return double-wall pipe 2, the methanol liquid inlet double-wall pipe 1 and the methanol liquid return double-wall pipe 2 are communicated with the methanol supercharging unit 3 to realize the liquid inlet and return of methanol when the methanol system is operated, a liquid return chain pipe valve 7 is installed and communicated between the methanol liquid return double-wall pipe 2 and the methanol supercharging unit 3, a communication valve 8 is installed between the methanol liquid inlet double-wall pipe 1 and the methanol liquid return double-wall pipe 2, one end of the high-pressure pipeline 4 is detachably communicated with the methanol supercharging unit 3, and the other end is correspondingly communicated with a plurality of methanol injectors 9, in the embodiment, the use and installation of each valve body, the methanol injector 9 and the double-wall pipe are all prior art, and excessive description is not given.

[0028] The marine low-speed diesel engine methanol injection system with air tightness detection function further comprises a fresh water supply system (not shown in the figure), a plugging tool 10 and methanol pressure detection sensors 11, the fresh water supply system is communicated with the methanol liquid inlet double-wall pipe 1 through the liquid inlet stop valve 5, the plugging tool 10 is detachably installed on the methanol supercharging unit 3 to block the communication port of the high-pressure pipeline 4 and the methanol supercharging unit 3, the methanol pressure detection sensors 11 are installed in plurality and are arranged on the methanol liquid inlet double-wall pipe 1 and the methanol liquid return double-wall pipe 2 to monitor the pressure of each pipeline part of the methanol injection system, the plurality of methanol pressure detection sensors 11 are connected with an external host control detection system, in the embodiment, the fresh water supply system adopts a fresh water supply pump, the host control detection system comprises but is not limited to a conventional PC and a PLC controller, can realize the communication and display with the methanol pressure detection sensors 11, and all are prior art, and excessive description is not given.

[0029] Further, the liquid inlet stop valve 5 is installed at a liquid inlet port of the methanol liquid inlet double-wall pipe 1, the liquid return stop valve 6 is installed at a liquid return port of the methanol liquid return double-wall pipe 2, and the methanol pressure detection sensors 11 are preferably installed in three and are respectively arranged before an inlet of the methanol supercharging unit 3, on a rear side of the liquid inlet stop valve 5 and before the liquid return stop valve 6.

[0030] With reference to Figure 1 And Figure 4The high-pressure pipeline 4 comprises at least three methanol high-pressure pipes 41 communicated with the methanol pressurizing unit 3, and the alcohol injector 9 is correspondingly provided with three methanol high-pressure pipes 41, the methanol high-pressure pipes 41 are double-wall pipes, and the methanol pressurizing unit 3 is integrally formed with a plurality of double-wall pipe connecting ports 31 correspondingly connected with the double-wall pipes 41, in the embodiment, the connecting port communication between the double-wall pipes is the prior art and will not be described in detail.

[0031] The sealing tool 10 comprises a sealing column 101, a sealing cover 102 and fastening bolts 103, the sealing column 101 and the sealing cover 102 are integrally formed, the sealing column 101 is inserted into the double-wall pipe connecting port 31 to realize sealing, the fastening bolts 103 are provided in plurality and are all threaded through the sealing cover 102 and are screwed with the outer wall of the methanol pressurizing unit 3, the sealing column 101 and the sealing cover 102 can be of any shape, in the embodiment, the sealing column 101 is preferably a cylindrical body and the outer wall of the end of the sealing column 101 inserted into the double-wall pipe connecting port 31 is provided with a conical surface, the sealing cover 102 is preferably a circular cover body coaxially arranged with the sealing column 101, and the plurality of fastening bolts 103 are uniformly arranged at intervals around the circumferential direction of the sealing cover 102.

[0032] The working principle of the methanol injection system of the marine low-speed diesel engine with the air-tightness detection function is as follows:

[0033] During the air-tightness detection process, the methanol in the methanol injection system is sealed by using 16bar sealing oil for the whole process;

[0034] When testing, first, the low-pressure pipeline air tightness detection is carried out, the high-pressure pipeline 4 is removed in advance, that is, the connection between the double-wall pipe connecting port 31 on the methanol supercharging unit 3 and the methanol high-pressure pipe 41 is disconnected, and then the double-wall pipe connecting port 31 on the methanol supercharging unit 3 is plugged by using the plugging tool 10, so that the low-pressure loop formed by the methanol liquid inlet double-wall pipe 1, the methanol liquid return double-wall pipe 2 and the methanol supercharging unit 3 is subjected to the tightness test. When testing, the liquid inlet stop valve 5, the liquid return chain pipe valve 7 and the communication valve 8 are opened to make the methanol liquid inlet double-wall pipe 1 and the methanol liquid return double-wall pipe 2 communicate, and the required amount of fresh water satisfying the test water pressure is injected into the methanol liquid inlet double-wall pipe 1 through the fresh water supply system to simulate the methanol liquid inlet environment; after the water filling is completed, the liquid inlet stop valve 5 and the fresh water supply system are closed, and the timed pressure maintaining test is carried out. In the embodiment, the fresh water with a pressure of 13 bar is injected into the methanol injection system, and the pressure maintaining test time is preferably 10 minutes; after the pressure maintaining test is carried out for 10 minutes, the data of the plurality of methanol pressure detection sensors 11 are read through the host control detection system, and it is confirmed that the pressure drop of the inlet and return pipe pressure sensors is less than 0.1 bar, so that it is confirmed that the methanol liquid inlet double-wall pipe 1, the methanol liquid return double-wall pipe 2 and the liquid inlet stop valve 5, the liquid return chain pipe valve 7 and the communication valve 8 have good sealing performance; if the pressure drop is too large, it can be judged that there is a leakage in the pipeline in the methanol liquid inlet double-wall pipe 1 and the methanol liquid return double-wall pipe 2, and the leakage point can be checked through the outer pipeline at the bottom of the valve group or the outer pipeline of the methanol liquid inlet double-wall pipe 1 and the methanol liquid return double-wall pipe 2 to check the water leakage and repair; after the repair, the above operation is repeated to finally achieve the result that the pressure drop is 0.1 bar in 10 minutes, which meets the pump pressure drop requirement, so that the air tightness detection of the low-pressure pipeline is completed.

[0035] After the low-pressure pipeline detection is completed, the high-pressure pipeline 4 is connected with the methanol supercharging unit 3 to carry out the whole machine tightness test of the high-pressure pipeline 4. When testing, the liquid return stop valve 6 is opened to drain the water in the pipeline, and all the methanol high-pressure pipes 41 of the high-pressure pipeline 4 are connected with the methanol supercharging unit 3; after the water storage is drained, the liquid return stop valve 6 is closed and the liquid inlet stop valve 5 is opened, the required amount of fresh water satisfying the test water pressure is injected into the pipeline, and the amount of fresh water injected is also 13 bar. The pressure maintaining and air tightness test operation is repeated to further check the leakage point to the high-pressure pipeline 4 and the methanol injector 9, the air tightness detection of the high-pressure pipeline 4 is realized by reading the data of the plurality of methanol pressure detection sensors 11, and the pump pressure requirement that the pressure drop is 0.1 bar in 10 minutes is met, so that the air tightness detection of the high-pressure pipeline 4 is completed.

[0036] The above merely describes preferred embodiments of the present application, and is not intended to limit the present application in any form or in essence. It should be noted that those skilled in the art can make some improvements and supplements without departing from the present application, and these improvements and supplements should also be considered as the protection scope of the present application. Any equivalent changes, modifications and evolutions made by those skilled in the art without departing from the spirit and scope of the present application, and all equivalent embodiments of the present application, are still within the scope of the technical solutions of the present application.

Claims

1. A methanol injection system for a marine low-speed diesel engine with airtightness detection function, characterized in that, The system includes a methanol injection system, which comprises a methanol inlet double-walled pipe (1), a methanol return double-walled pipe (2), a methanol boosting unit (3), and a high-pressure pipeline (4). The methanol inlet double-walled pipe (1) is equipped with an inlet shut-off valve (5), and the methanol return double-walled pipe (2) is equipped with a return shut-off valve (6). Both the methanol inlet double-walled pipe (1) and the methanol return double-walled pipe (2) are connected to the methanol boosting unit (3), and a return chain valve (7) is connected between the methanol return double-walled pipe (2) and the methanol boosting unit (3). A connecting valve (8) is provided between the methanol inlet double-walled pipe (1) and the methanol return double-walled pipe (2). One end of the high-pressure pipeline (4) is detachably connected to the methanol boosting unit (3), and the other end is connected to multiple methanol injectors (9). It also includes a fresh water supply system, a sealing fixture (10) and a methanol pressure detection sensor (11). The fresh water supply system is connected to the methanol inlet double-wall pipe (1) through the inlet shut-off valve (5). The sealing fixture (10) is detachably installed on the methanol booster unit (3) to seal the connection between the high-pressure pipeline (4) and the methanol booster unit (3). Multiple methanol pressure detection sensors (11) are provided and are respectively installed on the methanol inlet double-wall pipe (1) and the methanol return double-wall pipe (2). Multiple methanol pressure detection sensors (11) are all connected to an external host control and detection system.

2. The marine low-speed diesel engine methanol injection system with airtightness detection function as described in claim 1, characterized in that, The high-pressure pipeline (4) includes at least three methanol high-pressure pipes (41) connected to the methanol boosting unit (3). The methanol high-pressure pipes (41) are double-walled pipes. The methanol boosting unit (3) is provided with multiple double-walled pipe connection ports (31) that are connected to the methanol high-pressure pipes (41) respectively.

3. The marine low-speed diesel engine methanol injection system with airtightness detection function as described in claim 2, characterized in that, The sealing fixture (10) includes a sealing post (101), a sealing cap (102), and fastening bolts (103). The sealing post (101) is inserted into the double-walled pipe connection port (31) to achieve sealing. The fastening bolts (103) are provided in multiples and all pass through the sealing cap (102) and are screwed to the outer wall of the methanol booster unit (3).

4. The marine low-speed diesel engine methanol injection system with airtightness detection function as described in claim 3, characterized in that, The outer wall of the end of the sealing post (101) that is inserted into the double-walled pipe connection port (31) is set in a conical shape.

5. The marine low-speed diesel engine methanol injection system with airtightness detection function as described in claim 3, characterized in that, The sealing post (101) is cylindrical, and the sealing cover (102) is a circular cover plate and is coaxial with the sealing post (101).

6. The marine low-speed diesel engine methanol injection system with airtightness detection function as described in claim 5, characterized in that, Multiple fastening bolts (103) are evenly spaced around the circumference of the cover (102).

7. The marine low-speed diesel engine methanol injection system with airtightness detection function as described in claim 2, characterized in that, Multiple methanol injectors (9) are provided corresponding to the methanol high-pressure pipe (41).

8. The marine low-speed diesel engine methanol injection system with airtightness detection function as described in claim 1, characterized in that, The liquid inlet shut-off valve (5) is located at the liquid inlet port of the methanol liquid inlet double-wall pipe (1), and the liquid return shut-off valve (6) is located at the liquid return port of the methanol liquid return double-wall pipe (2).

9. The marine low-speed diesel engine methanol injection system with airtightness detection function as described in claim 8, characterized in that, Three methanol pressure sensors (11) are provided and are respectively located in front of the inlet of the methanol booster unit (3), behind the liquid inlet shut-off valve (5), and in front of the liquid return shut-off valve (6).

10. The marine low-speed diesel engine methanol injection system with airtightness detection function as described in claim 1, characterized in that, The freshwater supply system includes a freshwater supply pump.

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