JP2021032830A - Extraction method of non-ferrous abrasion powder from grease in lubrication diagnosis - Google Patents

Abstract

To provide a method of efficiently extracting non-ferrous abrasion powder from grease while preventing filtration filter clogging as a premise for analysis of non-ferrous abrasion powder in lubrication diagnosis.SOLUTION: A method of efficiently extracting non-ferrous abrasion powder from grease in a lubrication diagnosis is a method of extracting non-ferrous abrasion powder generated in the grease as a premise of lubrication diagnosis for diagnosing the state of a machine. The method includes: a stirring step of, after adding a dilute and a separation aid that has a specific gravity between the non-ferrous abrasion powder and the additive/thickener, stirring grease that includes non-ferrous abrasion powder, which is a sample oil; a separation step of separating into layers of non-ferrous abrasion powder, separation aid, additive sthickeners, and diluents by centrifuging the stirred product with a centrifuge device; a disposing step of disposing of additives/thickeners and diluents out of the multiple layers; and an extraction step of, after adding diluent to the remaining layer and stirring the same, extracting non-ferrous abrasion powder by allowing to pass through a filtration filter.SELECTED DRAWING: Figure 1

Description

The present invention relates to a lubrication diagnosis for diagnosing the state of a machine by analyzing wear powder generated in the lubricating oil due to the operation of the machine, and particularly to a method for extracting non-iron wear powder generated in grease as a premise of the analysis.

A general maintenance method for mechanical equipment such as rotating / driving devices and hydraulic devices is predictive maintenance, which determines the necessity and timing of repair by diagnosing the condition of the mechanical equipment.
For such predictive maintenance, it is necessary to diagnose the condition of machinery and equipment, but since wear debris is generated in the lubricating oil during operation of machinery and equipment, the condition of machinery and equipment can be determined by analyzing this wear debris. Can be diagnosed.

Lubricating oils to be subject to lubrication diagnosis include oil and grease, but the demand for grease lubrication diagnosis is increasing, and its efficiency is required to be improved.
As a method for diagnosing grease lubrication, analytical pherography in which wear debris is attracted to a glass plate by magnetic force and observed with a microscope, or after diluting grease containing wear debris, it is passed through a filter and observed with a microscope. There is a filtration diagnostic method to analyze.

If the abrasion powder is a magnetic material such as iron-based abrasion powder, analytical pherography can be applied, but if the abrasion powder is non-ferrous abrasion powder, it cannot be attracted by magnetic force, so analytical pherography is generally used. Not applicable.
However, when the abrasion powder is non-ferrous abrasion powder, it may remain on the glass plate on the iron-based abrasion powder, and it may be observed by analytical ferrography, but it is difficult to determine.
Therefore, when the abrasion powder is non-ferrous abrasion powder, the filtration diagnostic method is applied.
However, grease has a problem that additives and thickeners are mixed in the base oil (base oil), and the additives and thickeners are clogged in the filtration filter in the filtration diagnosis. If the filtration filter is clogged, the sample oil cannot flow any more, so that it is not possible to collect wear debris from the specified amount of sample oil required for diagnosis, and there is a possibility that proper diagnosis cannot be made.

Therefore, it is necessary to remove additives and thickeners that cause clogging of the filter from the grease before filtration.
In this regard, as a method for separating suspended matter from oil, for example, Patent Document 1 proposes "a method for removing particles suspended in oil in a centrifuge from polluted oil".

Japanese Unexamined Patent Publication No. 2011-32477

The method described in Patent Document 1 is a method for removing suspended matter from the sample oil, and cannot be applied to separate and remove the additive / thickener present in the grease which is the sample oil.

The present invention has been made to solve such a problem, and as a premise of analysis of non-iron wear powder in lubrication diagnosis, clogging of a filtration filter is prevented and non-iron wear powder existing in grease is efficiently extracted. The purpose is to get a way to do it.

The method for extracting non-iron wear debris in grease in the lubrication diagnosis according to the present invention is the premise of the analysis in the lubrication diagnosis in which the state of the machine is diagnosed by analyzing the wear debris generated in the grease due to the operation of the machine. It is a method of extracting non-iron wear powder generated in
A stirring step of adding a diluent and a separation auxiliary liquid having a specific gravity between the non-ferrous metal wear powder and an additive / thickener to grease containing non-ferrous metal wear powder as a sample oil and stirring the mixture.
A separation step in which the stirred material is centrifuged by a centrifuge and separated into layers of non-ferrous abrasion powder, separation auxiliary liquid, additive / thickener, and diluent.
Of the multiple layers, the disposal process of discarding additives / thickeners and diluents,
It is characterized by comprising an extraction step in which a diluent is put into the remaining layer, stirred, and then passed through a filtration filter to extract non-ferrous wear powder.

According to the present invention, it is possible to remove additives and thickeners that cause clogging of the filtration filter and allow the sample oil to pass through the filtration filter efficiently. Therefore, an appropriate amount of grease should be used for the filtration diagnosis. This makes it possible to improve the accuracy of diagnosis, enable filtration diagnosis in a short time, and reduce costs.

It is explanatory drawing explaining the process flow of embodiment of this invention. It is a figure which shows the state in the test tube which carried out the stirring process in an Example. It is a figure which shows the state in the test tube which performed the centrifugation in an Example. It is a figure which shows the lower layer of FIG. 3 enlarged. As a comparative example, it is a figure which shows the state in the test tube centrifugally separated without using the separation auxiliary liquid. In the Example, it is a figure (a) which shows the state of the filtration filter which filtered the sample oil to which this invention was applied, and the microscopic enlarged view (b) of the extracted non-ferrous wear powder. In Examples, it is a figure (a) which shows the state of the filtration filter which filtered the sample oil as a comparative example to which this invention is not applied, and the microscopic magnified view (b) of the extracted wear debris.

The method for extracting non-iron wear debris in grease in the lubrication diagnosis according to the present embodiment is premised on the analysis in the lubrication diagnosis in which the state of the machine is diagnosed by analyzing the wear debris generated in the grease due to the operation of the machine. It is a method for extracting non-iron wear powder generated therein, and as shown in FIG. 1, includes a stirring step, a separation step, a disposal step, and an extraction step.
Hereinafter, each step will be described in detail.

<Stirring process>
The stirring step is a step of adding a diluent and a separation auxiliary liquid having a specific gravity between the non-iron wear powder and the additive / thickener to the grease containing the non-iron wear powder as the sample oil and stirring.
Specifically, for example, a sample oil, a diluent, and a separation auxiliary liquid are placed in a container that can be attached to a centrifuge such as a test tube and stirred.
The diluent may be any as long as it can dilute grease, and for example, a cleaning solution for machinery and equipment can be used.

Since the separation auxiliary liquid extracts wear powder containing non-iron wear powder (hereinafter, simply referred to as "non-iron wear powder") by the difference in specific gravity, it is a liquid having a specific gravity between the non-iron wear powder and the additive / thickener. Is not particularly limited as long as it is a liquid having such a specific gravity. However, it is more preferable if it does not contain impurities other than liquid and does not dissolve the filtration filter.
Specific examples of the separation auxiliary solution include a microclean diluted solution obtained by diluting Microclean (trade name) with water. In addition to this separation auxiliary solution, a penetrant inspection cleaning solution having an affinity for grease is used at the same time as a dilution solution. The penetrant inspection cleaning solution has an affinity for grease, and has the property that oils dissolve but additives and conditioners do not.
On the other hand, the penetrant inspection cleaning solution has no affinity with the microclean diluted solution.
The components and specific gravities of the penetrant inspection cleaning liquid, grease, separation auxiliary liquid, and non-ferrous abrasion powder (non-ferrous metal) are as shown in Table 1 below.

When the penetrant inspection cleaning solution is used as a separation auxiliary solution for centrifugation, three layers of "non-ferrous metal", "additives and extinguishing agents", and "separation auxiliary solution (penetrant inspection cleaning solution)" are formed.
In this state, the layer separation of the "nonferrous metal" and the "additive, tempering agent" is not sufficient.
Therefore, when the microclean dilute solution and the penetrant inspection cleaning solution are used at the same time for centrifugation, "non-ferrous metal", "microclean dilute solution", "additives, conditioning agents", and "separation auxiliary solution (penetrant inspection cleaning solution)" 4 layers are formed, and a layer of "microclean dilute solution" is formed between "nonferrous metal" and "additive, conditioner", so a layer of "nonferrous metal" and "additive, conditioner" Separation can be performed reliably.

<Separation process>
The separation step is a step of centrifuging what has been stirred in the stirring step with a centrifuge.
By centrifuging the sample in the test tube with a centrifuge, the sample is separated into a plurality of layers in the order of non-ferrous abrasion powder, separation auxiliary liquid, additive / thickener and diluent from the bottom side of the test tube.

<Disposal process>
The disposal step is a step of discarding the layers of the additive / thickener and the diluent in the upper layer, leaving the non-ferrous abrasion powder and the separation auxiliary liquid in the lower layer among the plurality of layers separated in the separation step.

<Extraction process>
The extraction step is a step in which the diluted solution is put into the layer remaining in the test tube again, stirred, and then passed through a filtration filter to extract the non-ferrous wear powder.
In this extraction step, the liquid that passes through the filtration filter does not contain additives or thickeners, so the filtration filter is not clogged and smooth filtration is possible even if the amount of liquid is large. ..
Non-ferrous wear powder is captured by the filtration filter, and the amount of non-ferrous wear powder required for diagnosis is extracted, enabling appropriate filtration diagnosis.

As described above, according to the present embodiment, the cause of clogging of the filtration filter is caused by performing centrifugal separation using a separation auxiliary liquid in consideration of the difference in specific gravity between the non-iron wear powder and the additive / thickener. Additives and thickeners can be separated and removed, and the amount of grease required for diagnosis can be filtered and diagnosed. As a result, the accuracy of the diagnosis is improved, the filtration diagnosis can be performed in a short time, and the cost can be reduced.

An experiment for extracting non-ferrous abrasion powder from grease was carried out based on the steps shown in the above-described embodiment, and this will be described below.
First, grease as a sample oil, a penetrant inspection cleaning solution as a diluent, and a factory detergent (more specifically, Microclean (trade name)) as a separation auxiliary solution were placed in a test tube and stirred.
Microclean (trade name) has a stock solution density (15 ° C.) of 1.10 g / cm3, and contains surfactants and rust preventives (diethanolamine, butyl cellosolve, potassium hydroxide, poly-nonylphenyl ether).
After stirring, as shown in FIG. 2, the mixture is uniformly mixed.

Next, after stirring as described above, the test tube was set in a centrifuge and centrifuged. The operation was carried out at a centrifuge speed of 5500 rpm for 5 minutes. As shown in FIG. 3, the inside of the test tube after centrifugation was separated into a plurality of layers in the order of non-ferrous abrasion powder, microclean, additive / thickener, and penetrant inspection diluent from the bottom side. The non-ferrous abrasion powder is submerged in the microclean as shown in FIG.
When the mixture is centrifuged without using the separation auxiliary solution, the state after stirring is almost the same as that shown in FIG. 2 as shown in FIG. 5 (a), but after the centrifugation, it is shown in FIG. 5 (b). As described above, the non-ferrous wear powder and the additive / thickener are accumulated in the same lower layer, and the additive / thickener and the non-ferrous wear powder cannot be separated.

Of the plurality of layers separated as described above, the upper layer of the additive / thickener and the diluent for penetrant detection is discarded, and then the diluent is added again to the layer remaining in the test tube and stirred. , Non-ferrous wear debris was extracted by passing through a filtration filter.

At this time, since the liquid passing through the filtration filter did not contain additives and thickeners, the filtration filter was not clogged and non-ferrous wear powder could be extracted on the filtration filter (Fig. 6 (Fig. 6). a) See). Further, as shown in FIG. 6B, in the example of the present invention, the non-ferrous wear powder can be clearly observed with a microscope.

As a comparative example, FIG. 7 shows the state of the filtration filter when the additive and the thickener are passed through the filtration filter without being separated. As shown in FIG. 7A, it can be seen that the filtration filter is clogged and the sample oil is accumulated on the filtration filter. In addition, it can be seen that it is difficult to observe with a microscope because sufficient sample oil cannot be poured and non-ferrous wear powder cannot be separated.

From the results of the above examples, it was demonstrated that the method for extracting non-ferrous wear powder in grease according to the present invention is effective.

Claims (1)

A method of extracting non-iron wear debris generated in the grease as a premise of the analysis in the lubrication diagnosis for diagnosing the state of the machine by analyzing the wear debris generated in the grease due to the operation of the machine.
A stirring step of adding a diluent and a separation auxiliary liquid having a specific gravity between the non-ferrous metal wear powder and an additive / thickener to grease containing non-ferrous metal wear powder as a sample oil and stirring the mixture.
A separation step in which the stirred material is centrifuged by a centrifuge and separated into layers of non-ferrous abrasion powder, separation auxiliary liquid, additive / thickener, and diluent.
Of the multiple layers, the disposal process of discarding additives / thickeners and diluents,
A method for extracting non-iron wear powder in grease in a lubrication diagnosis, which comprises an extraction step of putting a diluent in the remaining layer, stirring the mixture, and then passing the mixture through a filtration filter to extract non-iron wear powder.