JP2013139735A - Method and device for cleaning supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for cleaning a supercharger to obtain a supercharger that is prevented from being corroded and has no adhered soot dust.SOLUTION: A method for cleaning a supercharger 1 includes: a step for spraying an alkaline detergent containing an alkaline substance stored in a detergent container 15 from an exhaust gas inlet 8 side at a predetermined timing into the superchrger 1; a step for calculating a predetermined gas velocity suitable for adhering the sprayed alkaline detergent to a turbine 2 based on the particle diameter and density of the alkaline substance; a step for detecting the velocity of exhaust gas in an outer diameter part of the turbine 2; and a step for controlling a spray timing so that the flow velocity of the exhaust gas decelerates down to the predetermined gas velocity or less, and the alkaline detergent is spayed at a timing such that temperature in the supercharger 1 exceeds the acid-dew point of sulfate.

Description

  The present invention relates to a supercharger cleaning method and a cleaning apparatus.

  In a supercharger, soot (carbon) is likely to be deposited in portions exposed to combustion gases such as moving blades and stationary blades. If the accumulation of dust is left unattended and the maintenance is neglected, the rotation of the turbine becomes unstable, which may cause damage to the turbocharger and stop the main engine. However, the accumulated dust is fixed inside the supercharger and cannot be easily removed.

  Examples of the method for removing the fixed dust include warm water immersion cleaning, blast cleaning, cleaning with a cleaning agent, solid cleaning, and water cleaning. Hot water immersion cleaning, blast cleaning, and cleaning with a cleaning agent are performed with the supercharger stopped. Solid cleaning and water cleaning are performed during operation of the supercharger. Currently, solid cleaning is mainly employed as a method for removing the adhered dust (see Patent Document 1).

  In the solid cleaning, the solid cleaning material is made to collide with the fixed dust so that the dust is physically removed. As the solid cleaning material, mainly used rice and walnut shells are used. Since the solid cleaning material is supplied with the air for miscellaneous purposes, it can be supplied from the cleaning tank toward the moving blades and the stationary blades without reducing the rotational speed of the turbine. The air into which the solid cleaning material is charged can be extracted or substituted with compressed air at the outlet of the supercharger blower (see Patent Document 2). In addition, solid cleaning, unlike water cleaning, does not cause parts damage due to thermal shock.

Japanese Patent Laid-Open No. 3-264736 (Claims) Japanese Utility Model Publication No. 1-159134 (the scope of claims for utility model registration and FIG. 1)

Since solid cleaning uses collision energy, it is effective to remove the dust that has stuck to the rotor blades, but the removal effect on the stationary blades where the flow is slow is limited. There is a problem.
In addition, since the dust once fixed is not easily removed, if a solid cleaning material having high hardness is introduced to enhance the cleaning effect, there is a problem that the wear of the blade tip portion is promoted.

In the supercharger, sulfuric acid is generated by combustion of sulfur contained in the fuel. There is a problem that sulfuric acid corrodes the inside of the supercharger. Patent Document 1 proposes to neutralize the condensed sulfuric acid by mixing Mg (OH) _{2 and the} like into a solid cleaning material, thereby suppressing corrosion in the water pipe. However, it is difficult to uniformly adhere to a portion where dust adhesion is to be prevented, and there is a technical problem.

  The present invention has been made in view of the above circumstances, and provides a supercharger cleaning method and a cleaning apparatus for preventing a corrosion and suppressing a dust deposit. The purpose is to do.

  In order to solve the above-mentioned problems, the following method is employed in the supercharger cleaning method and cleaning apparatus of the present invention.

  The present invention relates to a turbine that is rotationally driven by exhaust gas guided from an internal combustion engine, a rotary shaft that is provided with the turbine at one end, and a rotary drive that is provided at the other end of the rotary shaft and is rotationally driven by the turbine. And a compressor for compressing air, wherein the alkaline cleaning agent containing an alkaline substance contained in a cleaning agent container is discharged from the exhaust gas inlet side at a predetermined timing. A step of spraying in the supercharger, a step of calculating a predetermined gas flow rate for the sprayed alkaline cleaning agent to adhere to the turbine based on the particle size and density of the alkaline substance, and the outside of the turbine Detecting the flow rate of the exhaust gas in the diameter portion, reducing the flow rate of the exhaust gas in the outer diameter portion of the turbine to the predetermined gas flow rate or less, and Machine provides a method for cleaning a supercharger and a step of controlling the timing of spraying so that the alkaline cleaner at a timing a temperature above the acid dew point of sulfuric acid is sprayed.

According to the above invention, the predetermined gas flow rate is calculated, and the alkaline cleaning agent is sprayed at the timing when the flow rate of the exhaust gas in the outer diameter portion of the turbine is equal to or lower than the predetermined gas flow rate. By doing so, the alkaline substance contained in the alkaline cleaning agent can be uniformly attached by the turbine. By adhering the alkaline substance to the turbine, it is possible to neutralize the sulfuric acid generated by the combustion of sulfur contained in the fuel. Thereby, corrosion of the turbine side member of the supercharger due to sulfuric acid can be prevented.
According to the said invention, an alkaline cleaning agent is spread | dispersed when the inside of a supercharger is the temperature exceeding the acid dew point of a sulfuric acid. Therefore, since it can neutralize before a sulfuric acid becomes a liquid, adhesion of the dust which uses the aggregated sulfuric acid as a binder can be suppressed. Further, when sulfuric acid is neutralized, it is converted into water having a low boiling point and evaporates due to a high temperature environment in the supercharger, so that there is no fear that a liquid component that can become a binder remains.

  In one embodiment of the present invention, it is preferable that a particle size of an alkaline substance contained in the alkaline detergent is 0.7 μm or more and 40 μm or less.

  The physical impact on the turbine can be suppressed by spraying fine alkaline substance as the alkaline cleaning agent. Thereby, it is possible to extend the life of the turbine.

  In one embodiment of the present invention, it is preferable that a predetermined amount of the alkaline cleaning agent is gradually sprayed over a predetermined time.

  Thereby, since the alkaline substance contained in the alkaline cleaner is easily dispersed by the exhaust gas, it can be more uniformly attached to the turbine.

  In one aspect of the invention described above, the alkaline substance derived from the alkaline detergent contained in the exhaust gas that has passed through the turbine is detected, and the predetermined timing is set so that the amount of the detected alkaline substance is within a predetermined value range. It is preferable to control.

  By detecting the alkaline substance contained in the exhaust gas that has passed through the turbine, it is possible to determine whether or not the sprayed alkaline substance adheres to the turbine as scheduled. When an alkaline substance exceeding a predetermined value is detected in the exhaust gas that has passed through the turbine, the spraying timing of the alkaline cleaning agent may be shifted until the flow rate of the exhaust gas at the outer diameter portion of the turbine is further slowed down.

  In one aspect of the invention described above, when the alkaline cleaning agent is solid, a hygroscopic agent having higher hygroscopicity than the alkaline cleaning agent is disposed at a position isolated from the alkaline cleaning agent in the cleaning agent container. It is preferable.

  When the alkaline cleaning agent is solid, the alkaline cleaning agent can be maintained in a dry state by disposing the adsorbent in the cleaning agent container and preferentially absorbing moisture in the container into the adsorbent. This facilitates dispersion in the exhaust gas when sprayed, so that the alkaline substance can be more uniformly attached to the turbine.

  The present invention also provides a turbine that is rotationally driven by exhaust gas guided from an internal combustion engine, a rotary shaft that is provided with the turbine at one end, and a rotary shaft that is provided at the other end of the rotary shaft and is rotationally driven. A cleaning device for a supercharger having a compressor that compresses air by being driven to rotate, wherein an alkaline cleaner containing an alkaline substance is accommodated, and the alkaline cleaner is contained in the supercharger using chore air. A cleaning agent container connected to the exhaust gas inlet side of the supercharger, a control unit for controlling the timing of spraying the alkaline cleaning agent, and a miscellaneous air inlet of the cleaning agent container. An electromagnetic valve, and the control unit detects a flow rate of the exhaust gas in an outer diameter portion of the turbine, and the sprayed alkaline cleaning agent adheres to the turbine. Calculation means for calculating the predetermined gas flow rate based on the particle size and density of the alkaline cleaning agent, based on the flow rate data of the exhaust gas in the outer diameter portion of the turbine detected by the detection means, The solenoid valve is opened and closed so that the alkaline cleaning agent is sprayed at a timing when the flow rate data of the exhaust gas decelerates to the predetermined gas flow rate or less and the temperature in the supercharger exceeds the acid dew point of sulfuric acid. A supercharger cleaning device is provided.

According to the above invention, the predetermined gas flow rate is calculated, and the alkaline cleaning agent is sprayed at the timing when the flow rate of the exhaust gas in the outer diameter portion of the turbine is equal to or lower than the predetermined gas flow rate. By doing so, the alkaline substance contained in the alkaline cleaning agent can be uniformly attached by the turbine. By adhering the alkaline substance to the turbine, it is possible to neutralize the sulfuric acid generated by the combustion of sulfur contained in the fuel. Thereby, corrosion of the turbine side member of the supercharger due to sulfuric acid can be prevented.
According to the said invention, an alkaline cleaning agent is spread | dispersed when the inside of a supercharger is the temperature exceeding the acid dew point of a sulfuric acid. Therefore, since it can neutralize before a sulfuric acid becomes a liquid, adhesion of the dust which uses the aggregated sulfuric acid as a binder can be suppressed. Further, when sulfuric acid is neutralized, it is converted into water having a low boiling point and evaporates due to a high temperature environment in the supercharger, so that there is no fear that a liquid component that can become a binder remains.

  In one embodiment of the present invention, it is preferable that a particle size of an alkaline substance contained in the alkaline detergent is 0.7 μm or more and 40 μm or less.

  The physical impact on the turbine can be suppressed by spraying fine alkaline substance as the alkaline cleaning agent. Thereby, it is possible to extend the life of the turbine.

  1 aspect of the said invention WHEREIN: It is preferable that the said solenoid valve is controllable so that it may open | release over predetermined time so that the said alkaline cleaning agent may be sprayed gradually.

  Thereby, since the alkaline substance contained in the alkaline cleaner is easily dispersed by the exhaust gas, it can be more uniformly attached to the turbine.

In one aspect of the invention, an exhaust port for exhaust gas that has passed through the turbine includes an alkali detection unit that detects an alkaline substance derived from the alkaline cleaner contained in the exhaust gas,
It is preferable that the controller can control the opening and closing of the solenoid valve so that the amount of the alkaline substance detected by the alkali detector is within a predetermined value range.

  By detecting the alkaline substance contained in the exhaust gas that has passed through the turbine, it is possible to determine whether or not the sprayed alkaline substance adheres to the turbine as scheduled. When an alkaline substance exceeding a predetermined value is detected in the exhaust gas that has passed through the turbine, the spraying timing of the alkaline cleaning agent may be shifted until the flow rate of the exhaust gas at the outer diameter portion of the turbine is further slowed down.

  1 aspect of the said invention WHEREIN: The said alkaline cleaning agent is solid, and the hygroscopic agent with higher hygroscopicity than the said alkaline cleaning agent is arrange | positioned in the position isolated from the said alkaline cleaning agent in the said cleaning agent container. Is preferred.

  When the alkaline cleaning agent is solid, the alkaline cleaning agent can be maintained in a dry state by disposing the adsorbent in the cleaning agent container and preferentially absorbing moisture in the container into the adsorbent. This facilitates dispersion in the exhaust gas when sprayed, so that the alkaline substance can be more uniformly attached to the turbine.

  According to the present invention, the timing of spraying the alkaline cleaning agent at a timing at which the flow rate of the exhaust gas at the outer diameter portion of the turbine is reduced to a predetermined gas flow rate or less and the temperature in the supercharger exceeds the acid dew point of sulfuric acid. By cleaning the turbocharger by controlling the above, it is possible to obtain a supercharger in which corrosion is prevented and adhesion of dust is suppressed.

It is a whole line figure of the washing device of a supercharger concerning one embodiment of the present invention. It is a figure which shows the example of attachment of the washing | cleaning apparatus to a supercharger. It is a schematic block diagram of the washing | cleaning apparatus which spreads the cleaning agent of a solid (powder) shape. It is a schematic block diagram of another washing | cleaning apparatus which spreads the cleaning agent of a solid (powder) shape. It is a schematic block diagram of the washing | cleaning apparatus which spreads the cleaning agent of a liquid (slurry) shape. It is a figure which shows the relationship between the particle size of magnesium hydroxide, and the predetermined | prescribed gas flow rate required in order to make it adhere to a turbine. It is a figure which shows the amount of magnesium hydroxide adhering per unit area of the turbine by spraying timing.

Hereinafter, an embodiment of a supercharger cleaning method and a cleaning apparatus according to the present invention will be described with reference to the drawings.
[First Embodiment]
In FIG. 1, the whole line figure of the washing | cleaning apparatus of the supercharger which concerns on this embodiment is shown. In FIG. 2, the example of attachment of the washing | cleaning apparatus to a supercharger is shown.

  A supercharger 1 to be cleaned includes a turbine 2 that is rotationally driven by exhaust gas guided from an internal combustion engine, a rotary shaft 3 that is provided with a turbine at one end, and a turbine 2 that is provided at the other end of the rotary shaft. And a compressor 4 that compresses air by being rotationally driven.

  The turbine 2 includes a turbine disk 5 and a turbine blade 6 that rotate by receiving exhaust gas, and is covered with a turbine casing 7. The turbine casing 7 has a turbine casing inlet 8 through which exhaust gas is guided from an exhaust gas collecting pipe (not shown) of the internal combustion engine, and a turbine casing outlet 9 that guides exhaust gas that has passed through the turbine blades 6 to the outside of the turbine. doing.

  The compressor 4 includes a compressor casing 10 and an impeller 11 that compresses air by being rotationally driven. The compressor casing 10 is provided so as to cover the impeller 11. The compressor casing 10 has a compressor casing inlet (suction port) 13 for taking in air from the outside through a silencer 12 and a compressor casing outlet 14 for discharging the air compressed by the impeller 11.

  One end of the rotating shaft 3 is connected to the turbine disk 5, and the other end is connected to the impeller 11 of the compressor 4. Therefore, when the turbine disk 5 is rotationally driven, the impeller 11 is also rotationally driven and air can be compressed.

The cleaning device includes a cleaning agent container 15, a solenoid valve 16, and a control unit 17.
The cleaning agent container 15 is a container that can accommodate an alkaline cleaning agent (hereinafter referred to as a cleaning agent), and includes a miscellaneous air inlet 18 and a miscellaneous air outlet 19. One end of a cleaning agent supply pipe 21 is connected to the choke air outlet 19 via a check valve 20. The other end of the cleaning agent supply pipe 21 is connected to the turbine casing inlet 8 (or a pipe connected to the turbine casing inlet 8) so that the cleaning agent can be sprayed from the cleaning agent container 15 into the supercharger (in the turbine casing). ing. An electromagnetic valve 16 is connected to the choke air inlet 18, and the amount of choke air introduced into the cleaning agent container 15 can be adjusted by the opening of the valve.

The control unit 17 includes a detection unit and a calculation unit, and can control the timing of spraying the cleaning agent.
The detection means can detect the flow rate of the exhaust gas in the outer diameter portion of the turbine 2 (the outer peripheral portion of the turbine blade 6). In the present embodiment, the detection means receives the rotation signal of the rotation shaft 3 and converts the received rotation signal into the exhaust gas flow velocity based on the diameter from the rotation shaft 3 to the outer periphery of the turbine blade 6 to thereby convert the turbine 2. The flow rate of the exhaust gas in the outer diameter part is detected. The detection means can also convert the rotation signal into the temperature inside the turbine casing. For example, a correlation between the rotational speed of the rotating shaft 3 (or the flow velocity of the exhaust gas in the outer diameter portion of the turbine 2) and the temperature change in the turbine casing is obtained in advance, and the rotation signal is converted into the turbine casing internal temperature based on the correlation.

  The calculation means can calculate a predetermined gas flow rate necessary for the sprayed cleaning agent to adhere to the turbine 2 based on the particle size and density of the cleaning agent.

  Based on the exhaust gas flow velocity data in the outer diameter portion of the turbine detected by the detecting means, the control unit 17 decelerates the exhaust gas flow velocity data to a predetermined gas flow velocity or less, and in the turbine casing (in the supercharger). The opening and closing of the solenoid valve 16 can be controlled so that the cleaning agent is sprayed at a timing when the temperature exceeds the acid dew point of sulfuric acid.

  In the present embodiment, an alkali detector may be provided at the turbine casing outlet 9 of the cleaning device (not shown). The alkali detection unit can detect an alkaline substance derived from an alkaline cleaner contained in the exhaust gas that has passed through the turbine blade 6. When the alkali detection unit is provided, the control unit 17 can control the opening and closing of the electromagnetic valve 16 so that the amount of the alkaline substance detected by the alkali detection unit is within a predetermined value range.

  In this embodiment, when the cleaning agent is solid (powder), a hygroscopic agent may be disposed in the cleaning agent container. The hygroscopic agent is covered with a material that allows only moisture to pass therethrough so as not to be supplied into the turbine casing together with the miscellaneous air, and is disposed at a position isolated from the cleaning agent. The hygroscopic agent is a substance having higher hygroscopicity than the cleaning agent, and is selected from, for example, calcium chloride, silica gel, or zeolite.

Next, a supercharger cleaning method according to this embodiment will be described.
As the cleaning agent, an alkaline cleaning agent containing an alkaline substance is used. Examples of the alkaline substance include magnesium hydroxide, calcium hydroxide, or calcium carbonate. The particle diameter of the alkaline substance is preferably 0.7 μm to 40 μm, and the average particle diameter (median diameter) is more preferably 2.9 μm to 3.9 μm. The physical impact on the turbine 2 can be suppressed by spraying fine alkaline substance as the alkaline cleaning agent.
The alkaline cleaning agent may be in a solid (powder) shape or a liquid (slurry) shape.

The alkaline detergent is sprayed from the exhaust gas inlet (turbine casing inlet 8) side toward the supercharger (turbine casing). The alkaline cleaning agent may be sprayed in a single spray in such an amount that the alkaline substance has a ratio of 700 cc to the area (m ² ) to be adhered.

  If the gas flow rate at the timing of spraying the alkaline cleaning agent is too fast, the alkaline substance is difficult to adhere to the turbine 2. Therefore, it is necessary to spray the alkaline cleaning agent at a predetermined gas flow rate or less. The supercharger cleaning method according to the present embodiment calculates a predetermined gas flow rate necessary for the alkaline substance contained in the sprayed alkaline cleaner to adhere to the turbine 2 based on the particle size and density of the alkaline substance. The process of calculating by a part is provided. Thereby, an alkaline substance can adhere to the turbine 2 more reliably.

The predetermined gas flow rate is calculated by, for example, the following formula (I). In formula (I), v _stick is the gas flow rate (m / s), γ is the surface tension (ergs · cm ⁻² ), ε is the Young's modulus (dyn · cm ⁻² ), and R is the particle size of the alkaline substance (μm) ), Ρ is the density (g · cm ⁻³ ) of the alkaline substance.

Further, the flow rate of the exhaust gas in the outer diameter portion of the turbine 2 is detected during operation of the supercharger. During the operation of the supercharger, the turbine is rotationally driven, so that the exhaust gas flow velocity at the outermost peripheral portion of the turbine is the fastest. Therefore, the alkaline substance can be uniformly attached to the turbine 2 by spraying the alkaline cleaning agent at a timing when the flow rate of the exhaust gas in the outer diameter portion of the turbine 2 becomes equal to or lower than the flow rate of the predetermined exhaust gas.
If the dimensions of the turbine 2 are known, the flow rate of the exhaust gas can be detected indirectly based on the rotation information of the turbine. The rotational speed of the turbine 2 (rotating shaft 3) correlates not only with the flow rate of the exhaust gas but also with the temperature in the turbine casing.
For example, when a turbine having a size of 0.6 m is rotating at 13,000 rpm, the flow rate of the exhaust gas in the outer diameter portion of the turbine 2 is about 400 m / s, and the temperature in the turbine casing is 400 ° C. to 550 ° C.

  The timing of spraying the cleaning agent is controlled by the control unit. Specifically, the control unit decelerates the flow rate of the exhaust gas in the outer diameter portion of the turbine to a predetermined gas flow rate or less, and sprays the cleaning agent at a timing when the temperature in the supercharger exceeds the acid dew point of sulfuric acid. Control the solenoid valve to do.

The acid dew point temperature of sulfuric acid assumed in superchargers for marine diesel engines depends on the fuel used and can vary, but it is 12 ppm sulfur trioxide (SO ₃ ) and 6.5% moisture (H ₂ O). In this case, it is about 131 ° C. Therefore, the cleaning agent is preferably sprayed at a timing at which the temperature inside the turbine casing is 131 ° C. or higher which will surely exceed the acid dew point.

  The temperature in the turbine casing is about 400 ° C. to 550 ° C. during operation of the supercharger, and when the supercharger stops operation, the temperature decreases as the rotational speed of the turbine 2 decreases. According to this embodiment, the sulfuric acid can be neutralized before the sulfuric acid is liquefied by spraying the alkaline cleaning agent at the above timing. For example, when the alkaline substance is magnesium hydroxide, magnesium sulfate and water are produced when the sulfuric acid is neutralized. Since magnesium sulfate is a solid (powder), it is exhausted from the turbine casing outlet 9 to the outside of the system by multiplying the flow of the exhaust gas. Further, in an environment where the temperature in the turbine casing is equal to or higher than the acid dew point of sulfuric acid, water evaporates and is taken out of the system through the turbine casing outlet 9 along with the flow of the exhaust gas.

When the present inventors analyzed the scale adhering to the turbine surface of the landing turbocharger, the pH was 2 to 3, sulfur (S) was 7 to 10%, and sulfuric acid (SO ₄ ) molecules were 2 to 3 However, oil (tar content) and low melting point compounds were hardly present. From this, according to this embodiment, since it can suppress that the liquid which can become a dust binder can generate | occur | produce and remain in a turbine casing, the adhesion of the dust to the turbine 2 is also suppressed, preventing the corrosion by a sulfuric acid. It will be possible.

  The opening and closing of the electromagnetic valve 16 may be controlled so as to be gradually opened over a predetermined time. For example, the valve is opened to the supercharger side so that the valve opening becomes 100% in 3 seconds or more. By adjusting the area of the conduit and introducing the cleaning agent, the cleaning agent can be more diffused by the exhaust gas.

  When the alkali detection unit is provided, the alkaline substance derived from the alkaline detergent contained in the exhaust gas that has passed through the turbine blade 6 is detected, and the detergent so that the amount of the detected alkaline substance is within a predetermined range. Control the timing of spraying. For example, the density of the alkaline substance in the previous exhaust gas in the exhaust gas after passing through the turbine blade 6 is greater than or equal to a preset value with respect to the density of the alkaline substance in the exhaust gas before passing through the turbine blade 6. In this case, it is determined that the spraying timing is too early, the spraying is temporarily stopped, and the spraying timing is readjusted.

FIG. 3 illustrates a schematic configuration diagram of a cleaning apparatus for spraying a solid (powder) -shaped cleaning agent. The cleaning device includes a cleaning agent container 25, a solenoid valve 26, and a control unit 27.
A conduit 24 is provided in the cleaning agent container 25 to guide the air for chores. The conduit 24 has one end connected to the chores air inlet 28 and the other end directed to the chores air outlet 29.
The cleaning agent container 25 includes a storage unit 30 that stores the cleaning agent. The accommodating part 30 has the cleaning agent addition port 31, and the edge part of this cleaning agent addition port 31 is arrange | positioned in the conduit | pipe. A fixed amount extrusion screw 32 and a driving pulse motor 33 are connected to the storage unit 30 as automatic cleaning agent filling means, and the cleaning agent stored in the storage unit 30 can be pushed out from the cleaning agent addition port 31.

  An electromagnetic valve 26 is provided outside the cleaning agent container of the chore air inlet 28. The electromagnetic valve 26 is a three-way valve, and the other valve seat side is connected with another conduit (cleaning agent supply pipe) 34 that guides the miscellaneous air directly to the turbine casing 7 without passing through the cleaning agent container 25. Yes.

  A controller 27 is connected to the electromagnetic valve 26 and the driving pulse motor 33. The control unit 27 controls the opening and closing of the electromagnetic valve 26 at a predetermined timing, and sends a predetermined pulse to the drive pulse motor 32 so that a predetermined amount of the cleaning agent is pushed out from the cleaning agent addition port 31, thereby determining the quantitative extrusion screw 32. Can be rotated.

In FIG. 4, the schematic block diagram of another washing | cleaning apparatus which spreads the cleaning agent of a solid (powder) shape is illustrated. The cleaning device includes a cleaning agent container 35, a solenoid valve 36, and a control unit 37.
In the cleaning agent container 35, a conduit 44 for guiding the air for miscellaneous purposes is provided. The conduit 44 has one end connected to the chores air inlet 38 and the other end directed to the chores air outlet 39.
The cleaning agent container 35 has a cleaning agent inlet 40 through which a cleaning agent can be supplied from a cleaning agent storage portion (not shown). The cleaning agent inlet 40 is provided in the upper part of the cleaning agent container 35, and the supplied cleaning agent is guided to the cleaning agent supply pipe 41 on the flow of miscellaneous air discharged from the conduit 44. The cleaning agent supply pipe 41 is preferably a heat-resistant flexible hose. This makes it possible to meet new needs for after-sales service.
A solenoid valve 36 is provided outside the cleaning agent container of the chore air inlet 38.

  The control unit 37 includes a tachometer 42 and a reset switch 43. The control unit 37 controls the opening and closing of the electromagnetic valve 36 at the timing when the rotational speed of the rotating shaft 3 measured by the tachometer 42 is equal to or less than the threshold value, and sends and outputs a relay signal to open and close the cleaning agent inlet 40. The timing at which the cleaning agent is introduced can be controlled.

FIG. 5 illustrates a schematic configuration diagram of a cleaning apparatus for spraying a liquid cleaning agent. The cleaning device includes a cleaning agent container 45, a solenoid valve (not shown), and a control unit (not shown).
The cleaning agent container 45 contains a liquid cleaning agent 46. In the cleaning agent container, a conduit 47 for guiding the air for miscellaneous purposes is provided. One end of the conduit 47 is disposed in the cleaning agent supply pipe 50, enters the cleaning agent container through the miscellaneous air inlet 48, and the other end is disposed so as not to touch the cleaning agent solution.
A cleaning agent spray tube 51 is attached to the cleaning agent container 45. One end of the cleaning agent spraying pipe 51 is disposed in the cleaning agent solution, and the other end is connected to the downstream side of the conduit 47 of the cleaning agent supply pipe 50 via the air port 49 for miscellaneous purposes.

  The solenoid valve is connected to the upstream side of the cleaning agent supply pipe 50. The control unit can adjust the opening and closing of the electromagnetic valve at a predetermined timing to control the timing of spraying the cleaning agent. When the solenoid valve is opened, part of the air for miscellaneous purposes is introduced into the cleaning agent container, and the pressure in the cleaning agent container is increased. Accordingly, the cleaning agent solution 46 is sprayed from the cleaning agent spray pipe 51 to the cleaning agent supply pipe 50 in a push-out manner.

(Example)
Magnesium hydroxide powder (particle size distribution: 0.75 to 15.56 μm, average particle size (median diameter) dv50 = 3.4 μm, density 2.36 g · cm ⁻³ ) was used as the alkaline detergent.

  FIG. 6 shows the result of calculating the predetermined gas flow rate necessary for adhering to the turbine by the formula (I) when the magnesium hydroxide is used. When magnesium hydroxide is used, the magnesium hydroxide can be attached to the turbine in the region below the straight line shown in FIG. According to FIG. 6, in this embodiment, magnesium hydroxide can be attached to the turbine by setting the flow rate of the exhaust gas at the outer diameter portion of the turbine to 14 m / s or less.

  Therefore, the alkaline cleaning agent was sprayed toward the turbine disk at the timing when the rotational speed of the rotating shaft was 13000 rpm or 200 rpm. In this embodiment, 13000 rpm corresponds to an exhaust gas flow velocity of about 400 m / s in the outer diameter portion of the turbine (roof blade), and 200 rpm corresponds to an exhaust gas flow velocity of about 6 m / s in the outer diameter portion of the turbine (robot blade). After spraying, the adhering matter on the turbine surface (the moving blade and the stationary blade) was wiped off by the smear method, analyzed by ICP (inductively coupled plasma), and the amount of magnesium hydroxide adhering to the turbine was compared. The results are shown in FIG. In the figure, the vertical axis represents the amount of magnesium hydroxide attached.

  According to FIG. 7, almost no magnesium hydroxide was adhered to the turbine (the moving blade and the stationary blade) to which the cleaning agent was sprayed at the rotation speed of 13000 rpm. On the other hand, in the turbine (rotor blade and stationary blade) sprayed with the cleaning agent at a rotation speed of 200 rpm, about 1000 times the amount of magnesium hydroxide was adhered as compared with that of 13000 rpm.

  From the above results, it was found that the timing of spraying is important when spraying the alkaline detergent into the supercharger. When an alkaline detergent is used together with a solid detergent as in Patent Document 1, since the rotational speed of the turbine cannot be reduced, the alkaline substance does not sufficiently adhere to the turbine, and a desired neutralization effect is obtained. I can't. On the other hand, according to the present embodiment, the alkaline cleaner is removed at a timing when the flow rate of the exhaust gas in the outer diameter portion of the turbine is reduced to a predetermined gas flow rate or less and the temperature in the supercharger exceeds the acid dew point of sulfuric acid. By spraying, not only can corrosion due to sulfuric acid be prevented, but also the generation of aggregated sulfuric acid serving as a dust binder can be suppressed, and the dust can be prevented from sticking. “The exhaust gas flow velocity at the outer diameter of the turbine decelerates to a predetermined gas flow velocity or less” means that the turbocharger is in the process of shutting down. Thus, since dust hardly adheres to the turbine, it is possible to omit maintenance for removing the stuck dust. Since the alkaline substance used for the alkaline cleaner is finer than the solid detergent, the impact on the turbine is reduced. Therefore, it is possible to extend the life of the turbine by omitting maintenance with the solid cleaning material.

  Moreover, the alkaline substance used for the alkaline cleaner is less expensive than a solid cleaning material conventionally used for dust removal (for example, a marine grid manufactured by Hikawa Marine Co., Ltd.). Further, since the alkaline cleaning agent is a chemical cleaning agent, the input amount can be small. Therefore, according to this embodiment, maintenance cost can be suppressed.

DESCRIPTION OF SYMBOLS 1 Supercharger 2 Turbine 3 Rotating shaft 4 Compressor 5 Turbine disk 6 Turbine blade 7 Turbine casing 8 Turbine casing inlet 9 Turbine casing outlet 10 Compressor casing 11 Impeller 12 Silencer 13 Compressor casing inlet 14 Compressor casing outlets 15 and 25 , 35, 45 Cleaning agent container 16, 26, 36 Solenoid valve 17, 27, 37 Control unit 18, 28, 38, 48 Miscellaneous air inlet 19, 29, 39, 49 Miscellaneous air outlet 20 Check valves 21, 34, 41 , 50 Cleaning agent supply pipes 24, 44, 47 Conduit 30 Storing part 32 Metering screw 33 Driving pulse motor 40 Cleaning agent inlet 42 Tachometer 43 Reset switch 46 Cleaning agent 51 Cleaning agent spraying tube

Claims (10)

A turbine that is rotationally driven by exhaust gas guided from an internal combustion engine; a rotary shaft that is provided with the turbine at one end; A method of cleaning a supercharger comprising:
A step of spraying an alkaline detergent containing an alkaline substance contained in a detergent container into the supercharger from an inlet side of the exhaust gas at a predetermined timing;
Calculating a predetermined gas flow rate for the sprayed alkaline cleaning agent to adhere to the turbine based on the particle size and density of the alkaline substance;
Detecting the flow rate of the exhaust gas in the outer diameter portion of the turbine;
The alkaline cleaning agent is sprayed at a timing when the flow rate of the exhaust gas in the outer diameter portion of the turbine is reduced to the predetermined gas flow rate or less and the temperature in the supercharger exceeds the acid dew point of sulfuric acid. A process for controlling the timing of spraying;
A method for cleaning a turbocharger.   The supercharger cleaning method according to claim 1, wherein the alkaline substance contained in the alkaline cleaner has a particle size of 0.7 μm or more and 40 μm or less.   The supercharger cleaning method according to claim 1 or 2, wherein a predetermined amount of the alkaline cleaning agent is gradually sprayed over a predetermined time.   2. The predetermined timing is controlled such that an alkaline substance derived from the alkaline cleaning agent contained in exhaust gas that has passed through the turbine is detected, and the amount of the detected alkaline substance is within a predetermined value range. Item 4. The supercharger cleaning method according to any one of Items 3 to 4. When the alkaline detergent is solid,
The supercharger cleaning according to any one of claims 1 to 4, wherein a hygroscopic agent having a higher hygroscopic property than the alkaline cleaning agent is disposed at a position isolated from the alkaline cleaning agent in the cleaning agent container. Method. A turbine that is rotationally driven by exhaust gas guided from an internal combustion engine, a rotary shaft that is provided with the turbine at one end, and a rotary shaft that is provided at the other end of the rotary shaft and rotationally driven by the turbine being driven to rotate to generate air. A supercharger cleaning device comprising: a compressor for compressing;
A cleaning agent container that contains an alkaline cleaning agent containing an alkaline substance and is connected to the exhaust gas inlet side of the supercharger so that the alkaline cleaning agent can be sprayed into the supercharger using air for miscellaneous purposes;
A control unit for controlling the timing of spraying the alkaline detergent;
A solenoid valve connected to the air inlet of the cleaning agent container;
With
The control unit is
Detecting means for detecting a flow rate of the exhaust gas in an outer diameter portion of the turbine;
Calculation means for calculating a predetermined gas flow rate for the sprayed alkaline cleaning agent to adhere to the turbine based on the particle size and density of the alkaline cleaning agent;
With
Based on the flow rate data of the exhaust gas in the outer diameter portion of the turbine detected by the detection means, the flow rate data of the exhaust gas is decelerated to the predetermined gas flow rate or less, and the inside of the supercharger has an acid dew point of sulfuric acid. A supercharger cleaning device that controls the opening and closing of the solenoid valve so that the alkaline cleaning agent is sprayed at a timing when the temperature exceeds.   The supercharger cleaning apparatus according to claim 6, wherein a particle size of the alkaline substance contained in the alkaline cleaner is 0.7 μm or more and 40 μm or less.   The supercharger cleaning device according to claim 6 or 7, wherein the electromagnetic valve is controllable to be opened over a predetermined time so that the alkaline cleaning agent is gradually sprayed. An exhaust port for exhaust gas that has passed through the turbine includes an alkali detection unit that detects an alkaline substance derived from the alkaline cleaner contained in the exhaust gas,
9. The control unit according to claim 6, wherein the control unit is capable of controlling opening and closing of the electromagnetic valve so that an amount of the alkaline substance detected by the alkali detection unit falls within a predetermined value range. Feeder cleaning device. The alkaline detergent is solid;
The supercharger according to any one of claims 6 to 9, wherein a hygroscopic agent having higher hygroscopicity than the alkaline detergent is disposed at a position isolated from the alkaline detergent in the detergent container. Cleaning device.

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