JPH10185897A - Neutralization testing device and method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To a neutralization testing device and method therefor capable of accurately measuring the speed of neutralization reaction of a liquid sample such as a lubricant. SOLUTION: A reagent injecting means 30, through which a reagent neutralizing a liquid sample is injected, is provided on a lid member 220, which forms an airtight container, in which the liquid sample is sealed. This reagent injecting means 30 is formed to include a reagent injecting opening 300 which penetrates the inside of the airtight container to its outside and an airtight sealing member 310 which blocks the reagent injecting opening 300 and which an injection needle 60 for injecting a reagent can penetrate. As no gas leakage occurs even after the penetration of the injection needle 60 because of the elasticity of the airtight sealing member 310, no changes in measurement conditions in the airtight container occur and it is therefore possible to obtain the accurate speed of neutralization reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a neutralization test apparatus and a neutralization test method for a liquid sample such as a lubricating oil, and more particularly to a method for measuring an acid neutralization rate of a cylinder oil which is a heavy lubricating oil. Can be used.

[0002]

2. Description of the Related Art Conventionally, lubrication with fats and oils has been frequently used in drive mechanisms such as engines. For example, in a marine engine, a cylinder oil for smoothly driving a piston in an engine cylinder is used in addition to a system oil used for smoothly operating a drive mechanism. Such a cylinder oil has the ability to drive the piston smoothly in an atmosphere of high temperature and high pressure inside the cylinder, and also neutralizes corrosive sulfur compounds generated in the cylinder due to the combustion of the fuel oil. And the ability to prevent piston corrosion is required.

Therefore, in developing cylinder oil, it is an important factor in the development of cylinder oil to accurately determine the acid neutralization rate as the performance of cylinder oil. For this reason, the performance of cylinder oil has been conventionally evaluated by determining the neutralization reaction rate of cylinder oil using an acid neutralization test apparatus. Here, an acid neutralization test device is a device in which cylinder oil as a liquid sample is sealed in a sealed container in which the internal temperature and pressure are kept constant, and sulfuric acid is injected by a syringe from a reagent inlet communicating with the inside of the sealed container. Is a test device for determining the rate of acid neutralization of cylinder oil by measuring the neutralization reaction time of cylinder oil with sulfuric acid.

[0004]

Conventionally, in such an acid neutralization test apparatus, an airtight valve is provided at the above-mentioned reagent inlet, and when sulfuric acid is injected, (1) the valve is opened and (2)
Insert a syringe needle and inject sulfuric acid, (3) close the valve,
It was done by a series of work. Conventionally, the acid neutralization rate of the cylinder oil has been determined using the time when the valve is closed as the cylinder oil neutralization reaction start time.

However, in a high-temperature region where the reaction speed is high, when the measurement is performed by the above-described acid neutralization test apparatus, gas leakage occurs with the opening of the valve, and the measurement conditions inside the sealed container change, so that In addition, there is a problem that the neutralization reaction rate cannot be accurately obtained. Further, in the conventional acid neutralization test apparatus, it is difficult to set measurement conditions in a high-temperature and high-pressure atmosphere such as an actual state in a cylinder.
For this reason, there is a problem that the cylinder oil having a high viscosity must be diluted and used at the time of measurement at room temperature, and the cylinder oil cannot be directly measured. Further, when the time when the valve is closed is set as the neutralization reaction start time as described above, a time lag occurs between the time and the actual neutralization reaction start time at which sulfuric acid comes into contact with the cylinder oil. For this reason, there is a problem that the neutralization reaction time until the reaction is completed, that is, the neutralization reaction rate cannot be accurately obtained.

The present invention has been devised to solve the above problems, and is a neutralization test apparatus and a neutralization test method capable of accurately measuring the neutralization reaction rate of a liquid sample such as lubricating oil. Is provided.

[0007]

According to the present invention, there is provided a neutralization test apparatus comprising: a sealed container in which a liquid sample is sealed; and a reagent for injecting a reagent for neutralizing the liquid sample into the sealed container. Reagent injecting means, temperature detecting means provided inside the closed container for contacting with the liquid sample and capable of confirming a temperature rise due to neutralization of the liquid sample, and neutralizing provided inside the closed container Pressure detecting means capable of confirming a pressure change in the closed container caused by the above, and the detecting means measures a temperature change of the liquid sample and a pressure change in the closed container with time to measure the liquid sample. A neutralization test apparatus for determining a neutralization rate of the reagent, wherein the reagent injection means is formed in the closed container and penetrates inside and outside; a reagent inlet is closed; and the inside of the closed container is airtight. State and And a hermetic seal member that, said hermetic seal member, the needle of the reagent injection is characterized in that has a penetrable.

Here, the liquid sample is a liquid product such as a refined petroleum product, a mineral oil other than petroleum, or a chemically synthesized product, and also includes solid and semi-solid fats and oils at room temperature. For example,
Cylinder oil and the like, which are a kind of heavy lubricating oil and have high viscosity at room temperature, are also included in the liquid sample. In short, any liquid sample under the measurement conditions such as temperature and pressure in the closed container is the liquid sample referred to herein. In addition, the hermetic sealing member includes not only those made of elastomers such as natural rubber and synthetic rubber, but also those made of soft synthetic resin. Including the body. Incidentally, the foam is preferably a closed-cell foam from the viewpoint of ensuring airtight performance. In short, the material of the airtight seal member may be appropriately determined according to the required performance in operation, such as the diameter of the penetrating injection needle, the atmosphere inside the closed container, and the like.

Further, the temperature detecting means may be any as long as it can detect a thermal change due to a reaction such as temperature or calorie, and includes, for example, a thermometer, a thermocouple, and the like. The pressure detecting means may be any means capable of detecting a pressure change in the closed vessel, and various known pressure sensors can be used. According to the present invention, it is possible to inject the reagent by penetrating the injection needle for injecting the reagent into the airtight means, so that the airtight state in the sealed container is maintained regardless of the injection operation, and the measurement is performed. An accurate neutralization reaction rate is required without any change in conditions.

[0010] In the above, it is preferable to employ a pressure-resistant container that can withstand even a high-temperature and high-pressure atmosphere. In other words, by making the sealed container a pressure-resistant container, the inside of the sealed container can be set to the measurement conditions of a high-temperature and high-pressure atmosphere, so that the measurement can be performed with the cylinder oil directly sealed in the sealed container. The neutralization reaction rate is required under conditions close to actual use conditions. Further, it is preferable that the closed container is provided with a heater for preventing dew condensation. That is, since the heater is provided in the closed container, dew condensation occurring on the inner surface of the closed container above the liquid surface of the liquid sample is prevented, and a more accurate neutralization reaction rate is required. Since such dew condensation is likely to occur at the upper part of the inner surface of the closed container, it is preferable that the heater is installed so as to surround the upper part of the closed container.

Further, it is preferable that a control temperature detecting means for contacting with the liquid sample and controlling the temperature of the liquid sample is provided in the closed container. Is preferably located at a position closer to the liquid surface of the liquid sample than the temperature detection part of the control temperature detecting means. That is, since the temperature detection part of the temperature detection means is located closer to the liquid surface, the temperature rise during neutralization, that is, the neutralization reaction start time is detected more quickly,
It is possible to obtain a more accurate neutralization reaction rate.

[0012] The neutralization test method according to the present invention may further comprise a reagent injecting means for injecting a reagent for neutralizing the liquid sample into the closed container, and a liquid injection device provided inside the closed container. Temperature detecting means for contacting with a sample and confirming a temperature rise due to neutralization of the liquid sample; and pressure detecting means provided inside the closed vessel and capable of confirming a pressure change in the closed vessel caused by neutralization. A neutralization test method for measuring a change in temperature of the liquid sample and a change in pressure in the closed container with time to determine a rate of neutralization of the liquid sample by these detection means, After injection, a time at which a temperature change or a pressure change of the liquid sample is confirmed by any one of the temperature detecting means and the pressure detecting means is defined as a neutralization reaction start time of the liquid sample. To. According to such an invention,
Either the temperature detecting means or the pressure detecting means makes it possible to immediately confirm an increase in temperature or pressure due to the neutralization reaction between the reagent and the liquid sample, and to accurately obtain the neutralization reaction rate of the liquid sample. .

In the above, the liquid sample is a lubricating oil,
When sulfuric acid is used as a reagent, it is preferable to employ the above-described neutralization test method. In particular, if the sealed container is a pressure-resistant container, it can be suitably implemented as a neutralization test method for non-diluted lubricating oil, for example, cylinder oil. That is, as described in the background art, it is necessary to accurately measure the neutralization reaction rate as the performance required for the lubricating oil of the piston in the engine cylinder, and the utility of the present invention is high in this respect. Further, by setting the inside of the closed vessel to a high-temperature and high-pressure atmosphere by using the closed vessel as a pressure-resistant vessel, it becomes possible to measure the neutralization reaction rate under conditions close to the actual atmosphere in the cylinder. Further, since the inside of the closed vessel can be set to a high-temperature and high-pressure atmosphere, the neutralization reaction rate can be accurately measured without diluting the cylinder oil having high viscosity at room temperature with a solvent or the like.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an internal structure of a neutralization test apparatus according to an embodiment of the present invention. The neutralization test device (acid neutralization test device) 10 includes a closed container 20, an acid injection unit 30 serving as a reagent injection unit provided on the upper portion of the closed container 20, and a temperature detection unit provided inside the closed container 20. And a thermocouple 40 for detecting acid injection, which is to be formed, and a cylinder oil 50 serving as a liquid sample is sealed in the closed container 20.

The sealed container 20 is provided with a container body 210 into which the cylinder oil 50 is poured, a cover member 220 for closing the container body 210 to ensure an airtight state, and a cover member 220 surrounding the container body 210. And a frame member 230 that is directly connected. Here, the lid member 220 and the frame member 230 are made of cast iron, and the container main body 210 is an integral product made of pressure-resistant glass. By hermetically joining these members, the closed container 20 can withstand an internal pressure of up to 1 MPa. It is a pressure-resistant container that can withstand. The container main body 210 is a substantially cylindrical member whose bottom is closed in a hemispherical shape and has an opening surface 211 formed on the top. On the outer periphery of the opening surface 211, a projection 212 projecting radially outward of the cylinder is provided. Is formed. In addition, on the outer peripheral surface near the bottom of the container body 210,
A heater 240 is provided for adjusting the temperature of the liquid sample (cylinder oil) 50.

The cover member 220 is a disk-shaped member that covers the opening surface 211 of the container main body 210. The cover member 220 includes an acid injection unit 30 and an acid injection detection thermocouple 40 described later.
In addition, a stirrer 250 for stirring the cylinder oil 50 and an oil temperature control thermocouple 260 serving as a control temperature detecting unit for controlling the oil temperature of the cylinder oil 50 are provided. The frame member 230 is a substantially cylindrical member that covers the outer surface of the container body 210 and is opened vertically.
1 is movably mounted up and down in FIG.
An outward projection 231 is formed on the opening surface on the upper side in FIG. 1 of the frame member 230 toward the outside in the radial direction of the cylinder, and the opening surface on the bottom side is formed on the opening surface on the bottom side toward the inside in the radial direction of the cylinder. An inward projection 232 is formed to protrude.
A heater 233 for preventing dew condensation is provided on the outer surface of the cylinder of the frame member 230.

The joining between the container body 210 and the lid member 220 is performed via a frame member 230. The lid member 220 is
The frame member 230 is joined to the frame member 230 by bolts 234 in the vicinity of the outer peripheral edge thereof.
And is in contact with the container main body 210 through the contact hole. Also,
An O-ring 213 is also interposed between the opening surface 211 of the container body 210 and the lower surface of the lid member 220, and the bolt 2
With the tightening of 34, the cushion 235 and the O-ring 213 are compressed and deformed, and the airtightness of the sealed container 20 is ensured. Although not shown in FIG.
In order to measure the internal pressure, a pressure sensor serving as a pressure detecting means for confirming a pressure increase in the system is provided inside the closed container 20 and connected to an external pressure sensor monitor.

The acid injection detecting thermocouple 40 includes a lid member 220.
1 together with the stirrer 250 and the oil temperature control thermocouple 260 are provided to extend downward. The thermocouple 40 for detecting acid injection and the thermocouple 260 for controlling oil temperature are:
The distal end serving as the temperature detecting section reaches below the liquid level of the cylinder oil 50, and the base end penetrates the lid member 220 and is connected to an external temperature detector 270. The tip of the thermocouple 40 for detecting acid injection is located closer to the liquid surface of the cylinder oil 50 than the tip of the thermocouple 260 for controlling oil temperature. The stirrer 250 has a shaft portion 251 and a propeller portion 252 formed at the tip of the shaft portion 251. The stirrer 250 is rotatably provided substantially at the center of the circular lid member 220 with the direction of extension thereof as an axis. ing. The base end of the shaft portion 251 is connected to a motor (not shown in FIG. 1) provided outside through the lid member 220. Although not shown in FIG. 1, a gas-tight seal is applied to the penetrating portion of the lid member 220, and the airtightness inside the sealed container 20 is maintained. Nor.

As shown in the sectional view of FIG. 2 and the exploded perspective view of FIG. 3, the acid injecting means 30 is provided on the above-mentioned lid member 220. The acid injection means 30 has an acid injection port 300 penetrating the inside and outside of the sealed container 20 and a disc-shaped rubber stopper 310 serving as an airtight sealing member. A member 320 is joined to the joining member 320, and the injection needle 60 is connected to the acid injection port 3
00 and a guide member 330
And a fixing member 340 for fixing the rubber plug 310 on the guide member 330.

The acid injection port 300 is formed in the lid member 220 so as to penetrate the inside and outside of the closed container 20.
On the upper surface in FIG. 1, a female screw portion 301 for joining the joining member 320 corresponding to the injection port 300 is formed. The rubber stopper 310 is a substantially disk-shaped member, and is formed of non-permeable silicone rubber from the front surface to the back surface. Even if a small hole penetrating from the front surface to the back surface is formed, the hole is formed of silicone rubber. The rubber plug 310 is closed by the elasticity of the rubber, and the airtightness of the rubber plug 310 is maintained. 2 and 3, the joining member 320 is a member having a shape in which cylindrical bodies having different diameters are joined up and down, and includes a male screw portion 321 formed on the outer surface of a lower small-diameter cylinder, and an upper large-diameter cylinder. A female thread 322 formed on the inner surface, and a tapered projection 323 is provided at the bottom of the female thread 322 along the direction in which the cylinder extends. When the male screw portion 321 is screwed into the female screw portion 301 of the acid injection port 300, the joining member 320 is connected to the acid injection port 3
00.

The guide member 330 is a substantially cylindrical member whose both end surfaces are open. As can be seen from FIG. 2, a flange-shaped handle 331 projecting outward in the radial direction is formed at an intermediate portion. In addition, a male screw part 332 is formed at the lower part of the outer surface of the cylinder, and a male screw part 333 is formed at the upper part. In addition, a concave portion 334 having an inverted taper shape is formed on the lower end surface in FIG. 2 of the guide member 330 along the outer periphery of the radial end surface of the cylinder. Then, the male screw portion 33 of the guide member 330
2 is screwed with the female screw portion 322 of the joining member 320,
The guide member 330 is joined to the joining member 320, and the projection 323 of the joining member 320 and the guide member 330 are joined together.
And the recess 334 are hermetically bonded via a seal tape (not shown in FIGS. 2 and 3).

The fixing member 340 is a cylindrical member having an upper end face closed and a lower end face open in FIG. 2, and an insertion hole 341 into which the injection needle 60 is inserted is formed in the upper end face. At the same time, a female screw portion 342 is formed on the inner surface of the cylinder. The rubber stopper 310 is inserted into the inside of the cylinder of the fixing member 340, and the fixing member 3
The 40 female screw portions 342 are screwed into the male screw portions 333 on the upper part of the guide member 330, and the rubber plug 310 is fixed in a compressed state by the closed end face of the fixing member 340 and the upper surface of the guide member 330.

The acid neutralization reaction rate of the cylinder oil 50 is measured by the above-described acid neutralization test apparatus 10 according to the following procedure. Cylinder oil 5 in container body 210
0 is sealed and the inside of the sealed container 20 is made airtight by the lid member 220. The temperature of the cylinder oil 50 is raised by appropriately using the stirrer 250 and the heaters 240 and 233, and the temperature detector 2 to which the thermocouple 260 for controlling the oil temperature is connected.
While confirming by 70, the measurement conditions inside the closed container 20 are adjusted to the set values. Next, sulfuric acid for neutralizing the cylinder oil 50 is put in a syringe in advance, and the injection needle 60 is passed through the rubber plug 310 through a hole 341 formed in the fixing member 340 constituting the acid injection means 30 to form a sealed container. 20, and a predetermined amount of sulfuric acid is injected into the closed container 20.

Immediately after the injection, the temperature change of the cylinder oil 50 is confirmed by the temperature detector 270 to which the thermocouple 40 for detecting the acid injection is connected, and the time when the temperature rise is confirmed is recorded as the start time of the acid neutralization reaction. I do. Then, after confirming the reaction start time, the pressure rise inside the closed container 20 is measured with time by the above-mentioned pressure sensor monitor, and the time when the pressure inside the closed container 20 becomes constant is recorded as the neutralization reaction end time. The pressure increase inside the closed container 20 is caused by carbon dioxide gas generated by a neutralization reaction between the cylinder oil 50 as a liquid sample and sulfuric acid as a reagent.

According to the above-described embodiment, the following effects can be obtained. By using the rubber stopper 310 for the acid injection means 30, even if the injection needle 60 passes through the rubber stopper 310, the hole of the injection needle 60 is closed by the elasticity of the rubber stopper 310. Therefore, the airtight state inside the closed container 20 can be maintained, and an accurate neutralization reaction rate can be measured without causing an error in measurement conditions due to gas leakage or the like. Further, since the rubber plug 310 is attached in a compressed state by the guide member 330 and the fixing member 340, the force for closing the hole formed by the injection needle 60 by the elasticity of the rubber plug is large, and the inside of the sealed container 20 is at a high pressure. However, the airtight state can be maintained.

Furthermore, by making the sealed container 20 capable of withstanding the internal pressure of 1MP, the measurement conditions inside the sealed container 20 can be made high-temperature and high-pressure conditions close to the actual inside of the cylinder. The required acid neutralization reaction rate is determined. Furthermore, by raising the temperature of the inside of the closed container 20, the viscosity of the cylinder oil 50 can be reduced, and the neutralization reaction rate can be determined in a state where the reaction (stirring) is easy. Therefore, the neutralization reaction rate can be obtained without diluting the cylinder oil 50 with the base oil, and an accurate neutralization reaction rate can be obtained.

Further, by setting the neutralization reaction start time to the time when the temperature of the thermocouple 40 for detecting acid injection changes, it is possible to almost eliminate the time lag from the actual neutralization reaction start time. The sum reaction rate can be determined. In particular, by arranging the tip of the acid injection detection thermocouple 40 near the liquid surface of the cylinder oil 50, it is possible to detect the reaction with sulfuric acid injected from the upper portion of the closed vessel 20 more quickly. In this respect, an accurate neutralization reaction rate can be obtained.

[0028]

Next, experimental results will be described below for comparing the performance of the neutralization test apparatus and neutralization test method of the present invention with the conventional acid neutralization test apparatus and neutralization test method. As the neutralization test device of the present invention, the neutralization test device 10 described in the above embodiment is used.
And the procedure described in the above embodiment was adopted as a neutralization test method. On the other hand, as a conventional neutralization test device,
A sealed container equipped with a pressure sensor, a thermometer (for controlling oil temperature), and an airtight valve (sulfuric acid injection port) was used, and a device equipped with a means capable of setting the cylinder oil contained in the container to a predetermined temperature was adopted. . The acid neutralization test was performed as follows. Put the cylinder oil in the sealed container, heat it, open the airtight valve when the temperature reaches the specified temperature, insert the injection needle, inject sulfuric acid, close the valve, close the temperature change in the reaction system and seal The change in pressure in the vessel was recorded with time to determine the neutralization reaction rate.

The components of the liquid sample used for the performance comparison were 75.5 wt% of base oil, 0.5 wt% of alkenyl succinimide and 24.0 wt% of TBN280 sulfonate. In addition, in this performance comparison, the time from the injection of sulfuric acid to the point in time when the increase in pressure inside the sealed container was detected, and the pressure inside the sealed container 30 seconds after injection of sulfuric acid were measured as characteristic values. The measurement conditions are as shown in Table 1.

[0030]

[Table 1]

Table 2 shows the measurement results.

[0032]

[Table 2]

As described above, the acid neutralization test apparatus 1 of the embodiment
If it is 0, the start time of the acid neutralization reaction can be grasped more accurately than in the past, and the accurate neutralization reaction speed of the cylinder oil can be obtained. In addition, since the airtightness of the closed container 20 is maintained during the measurement, the closed container 20
An accurate neutralization reaction rate can be obtained without a change in the measurement conditions.

The present invention is not limited to the above-described embodiment, but includes the following modifications. That is, in the above-described embodiment, the reagent injection means (acid injection means) 30 is replaced with the reagent injection port (acid injection port) 300.
, Rubber plug 310, joining member 320, guide member 3
30 and the fixing member 340,
The present invention is not limited to this, and may be a reagent injection means 90 as shown in FIG. In FIG. 4, the reagent injection means 90 has a reagent injection port 900 and a rubber stopper 310. The reagent injection port 900 has an externally threaded portion 910 which protrudes outward. The fixing member 920 is screwed so as to sandwich the stopper 310, and the rubber stopper 310 is fixed. In short, the rubber stopper only needs to be a structure that can be fixed to the reagent inlet without gas leakage and can penetrate the injection needle even if the pressure inside the sealed container becomes high.

In the above-described embodiment, the acid neutralization test is performed using the cylinder oil 50 for marine engines as a liquid sample. However, the present invention is not limited to this, and the same applies to engine oils for automobiles and other lubricating oils. The same test can also be performed by dissolving a semi-solid material such as grease to obtain a liquid sample. Furthermore, in the above-described embodiment, the neutralization reaction test was performed using sulfuric acid as a reagent. However, the present invention is not limited to this. In the neutralization reaction test using a basic reagent such as sodium hydroxide, the neutralization reaction according to the present invention is performed. Test equipment and neutralization test methods may be utilized. In addition, specific structures, shapes, and the like at the time of carrying out the present invention may be other structures and the like as long as the object of the present invention can be achieved.

[0036]

According to the neutralization test apparatus and the neutralization test method of the present invention as described above, the neutralization reaction start time can be accurately detected without changing the measurement conditions due to gas leakage or the like. Therefore, the neutralization reaction of the liquid sample can be accurately measured.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an internal structure of a neutralization test device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a structure of a reagent injection unit according to the embodiment.

FIG. 3 is an exploded perspective view of a reagent injecting unit according to the embodiment.

FIG. 4 is a cross-sectional view illustrating a reagent injecting unit that is a modification of the reagent injecting unit in the above-described embodiment.

[Explanation of symbols]

 Reference Signs List 20 sealed container 30 reagent injection means 40 detection means 50 liquid sample 60 injection needle 300 reagent injection port 310 airtight seal member

Claims (8)

[Claims] 1. A closed container in which a liquid sample is sealed, a reagent injecting means for injecting a reagent for neutralizing the liquid sample into the closed container, and a reagent provided inside the closed container. Temperature detection means for contacting with the liquid sample and confirming a temperature rise due to neutralization of the liquid sample; and pressure detection provided inside the closed vessel and capable of confirming a pressure change in the closed vessel caused by the neutralization. A neutralization test apparatus for measuring the temperature change of the liquid sample and the pressure change in the closed container with time to determine the neutralization rate of the liquid sample by these detection means, The reagent injection means includes a reagent injection port formed in the closed container and penetrating inside and outside, and an airtight seal member for closing the reagent injection port and sealing the inside of the closed container with air. A neutralization test apparatus, wherein the injection member for injecting the reagent is penetrable through the needle member. 2. The neutralization test apparatus according to claim 1, wherein the sealed container is a pressure-resistant container. 3. The neutralization test apparatus according to claim 1, wherein the sealed container is provided with a heater for preventing dew condensation. 4. The neutralization test device according to claim 1, wherein the neutralization test device is provided inside the closed container to contact with the liquid sample and to control the temperature of the liquid sample. Wherein the temperature detecting portion of the temperature detecting portion is located at a position closer to the liquid surface of the liquid sample than the temperature detecting portion of the control temperature detecting portion. Testing equipment. 5. A closed container in which a liquid sample is sealed, a reagent injecting means for injecting a reagent for neutralizing the liquid sample into the closed container, and a reagent provided inside the closed container. Temperature detecting means for contacting with the liquid sample and confirming a temperature rise due to neutralization of the liquid sample; and pressure detecting means provided inside the closed vessel and capable of confirming a pressure change in the closed vessel caused by the neutralization. A neutralization test method for measuring a change in temperature of the liquid sample and a change in pressure in the closed container with time to obtain a neutralization rate of the liquid sample by these detection means, A neutralization test method, wherein a time at which a temperature change of the liquid sample is confirmed by the temperature detecting means after the injection of the reagent is defined as a neutralization reaction start time of the liquid sample. 6. The neutralization test method according to claim 5, wherein the liquid sample is a lubricating oil, and sulfuric acid is used as a neutralizing reagent for neutralizing the lubricating oil. 7. The neutralization test method according to claim 6, wherein the sealed container is a pressure-resistant container, and the lubricating oil is a non-diluted lubricating oil. 8. The neutralization test method according to claim 6, wherein the lubricating oil is a non-diluted cylinder oil.