Method for formulating required value of spectral detection element content of lubricating oil of aero-engine

Abstract

The invention discloses a method for formulating an element content required value of aero-engine lubricating oil spectrum detection. The method comprises the following steps: determining the element content required value according to a concentration alarm value, a concentration limit value and an 1h wear rate limit value; all material characteristics and friction areas of engine lubricating oil circuit parts are determined according to an engine, then elements with required values needing to be set are determined according to analysis and statistics results, the required values are set according to actual lubricating oil spectrum results, and blind value setting is avoided.

Description

Technical Field

[0001] The invention relates to a method for formulating a required value of element content in spectrum detection of aviation engine lubricating oil, belonging to the technical field of aviation engines. Background Art

[0002] When the engine is working, the wear of the relatively moving parts inside it will produce metal chips, which will mix with the lubricating oil and participate in the lubricating oil circulation. Among them, the larger particles will be intercepted by the oil filter or the metal chip end signal detector, and a large number of fine particles will be suspended in the lubricating oil, thus affecting the particle size of the lubricating oil and the content of the elements detected by the spectrum.

[0003] Lubricating oil spectrum detection and analysis Regular sampling to determine the content of each element in the lubricating oil, and combined with the material composition of the moving parts lubricated by the lubricating oil, it can be understood whether the wear state of each component is normal and monitor the occurrence of abnormal wear failures. Therefore, it is necessary to formulate the required value of the element content of lubricating oil spectrum detection. If the element requirement value is set too small, the element content often exceeds the standard when the engine is working normally, which will increase the engine troubleshooting time and reduce the engine utilization rate. If the element requirement value is set too large, abnormal wear of the engine cannot be detected, causing engine damage. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a method for formulating the required value of element content in aircraft engine lubricating oil spectrum detection.

[0005] The present invention is achieved through the following technical solutions.

[0006] The present invention provides a method for formulating a required value of element content in aircraft engine lubricating oil spectrum detection, comprising: determining the required value of element content by using a concentration alarm value, a concentration limit value, and a 1h wear rate limit value.

[0007] The wear rate calculation formula for the 1h wear rate limit value is as follows:

[0008] Wear rate = (C t -C t ′) / (TT′);

[0009]

[0010] The beneficial effects of the present invention are as follows: the material properties and friction areas of engine oil circuit parts are determined according to the engine, the elements for which required values ​​need to be formulated are determined according to the analysis and statistical results, and the required values ​​are formulated in combination with the actual oil spectrum results to avoid blind setting of values. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the process of the present invention; DETAILED DESCRIPTION

[0012] The technical solution of the present invention is further described below, but the scope of protection claimed is not limited to the description.

[0013] refer to Figure 1 shown.

[0014] The present invention provides a method for formulating a required value for element content in aircraft engine lubricating oil spectral detection, comprising the following steps.

[0015] Step 1: Determine the statistical principles and scope: Determine and classify the parts with relative motion, moving parts and parts susceptible to wear in the engine oil flow channel; gears, gear housings, bearings, transmission shafts / rods, bearings and gear bushings and other parts must be included in the statistics, among which the rollers, cages and raceways in the bearings are each considered as a single part, and the coating is also considered as a single part. The outer housing close to the rotating parts must also be included in the statistics; plastic parts such as sealing rings and graphite do not need to be counted; active metals do not need to be counted.

[0016] Step 2: Count the number of parts, material composition and friction area: Count the number of parts, query and determine the chemical composition of each part, and count the friction area of ​​each part.

[0017] Step 3, determine the types of elements: list the matrix elements of each material as the main elements, and list the 3-4 alloy elements with the highest content and the directional alloy elements as the auxiliary elements. Si element is usually not contained in alloys and sealing rings or its content is very small, but lubricating oil is easily mixed with Si element impurities in the air, so it should be included in the control.

[0018] Step 4: Element sorting: Comprehensively analyze the number of parts, element content and friction area, and comprehensively sort the size values ​​of the determined elements.

[0019] Step 5: Build a standard framework: List the element growth calculation formula, element requirement value framework and the processing flow after the element exceeds the standard. The general framework is as follows:

[0020] a) Element content requirement

[0021] The required values ​​of element contents based on XX testing instrument are shown in Table 1.

[0022] Table 1 Required values ​​of elements detected by engine XX instrument lubricating oil spectrum

[0023]

[0024]

[0025] b) Calculation of element content

[0026] 1) Wear rate: The rate of change of concentration per hour between two samplings (ppm / h), which indicates the growth trend of wear. The calculation formula is as follows:

[0027] Wear rate = (C t -C t ′) / (TT′)........(1)

[0028] Where:

[0029] Ct——corrected concentration value of a certain wear metal in this sample, ppm;

[0030] Ct′——corrected concentration value of the same wear metal measured in the last sample, ppm;

[0031] T——the total working time of the lubricating oil in the engine during this sampling, h;

[0032] T′——The total working time of the lubricating oil in the engine when the last sampling was taken, h.

[0033] 2) Corrected concentration of a certain element: The calculated concentration value considering the consumption of lubricating oil (the consumed lubricating oil is replenished by adding new lubricating oil). The calculation formula is as follows:

[0034]

[0035] Where:

[0036] Ct——corrected concentration value calculated after this sampling, ppm;

[0037] C——the concentration value measured after this sampling, ppm;

[0038] C′——the concentration value measured after the last sampling, ppm;

[0039] V——Total lubricating oil volume after this stop (the sum of the oil volume in the lubricating oil tank and the oil volume swallowed by the lubricating oil circuit), L;

[0040] V′——Total amount of lubricating oil after the last stop (the sum of the oil in the lubricating oil tank and the oil intake of the lubricating oil circuit), L.

[0041] C) Instructions for use

[0042] The following table lists the treatment instructions for situations where the main element content is higher than the warning value, the main element content is higher than the limit value, and the Fe element is higher than the wear rate limit value.

[0043] 6. Determine the required value of each element: According to the lubricating oil spectrum results of the first 10 times (or more, but must be counted from the first spectrum value) of a certain engine, formulate the required value of the element. The required value is determined as follows:

[0044] 1) Determination of the Fe element. The Fe element matrix parts usually account for the largest proportion in terms of quantity and friction area. The Fe element limit value = the maximum value measured result + 10 × (the proportion of the Fe element part material matrix + the proportion of the Fe element friction area) / 4.

[0045] 2) Determination of Cu element. Cu element matrix parts are usually used in easily worn locations such as transmission shafts, gears, gear journal bushings and bearing retainers. The Cu element limit value = the maximum value measured result + 10 × (Cu element part material matrix ratio + Cu element friction area ratio) + 1 ± 0.5.

[0046] 3) Determination of Si element: The Si element is set to 60ppm±30ppm depending on the engine conditions.

[0047] 4) Determination of Al element. Al element is usually used in oil pumps and casings that are prone to wear. The Al element limit value = the maximum value measured result + 100 × (Al element part material matrix ratio + Al element friction area ratio) / 2 ± 1.

[0048] 5) Determination of Mg element. Mg element is usually used as a part that is easily worn, such as pumps and casings. The limit value of Mg element = the maximum value measured result + 100 × (Mg element part material matrix ratio + Mg element friction area ratio).

[0049] 6) Determination of other elements. They can be arranged in order according to the statistical elements, and usually the maximum value of the measured result is set plus 0.5ppm~2ppm.

[0050] 7) The concentration alarm value is 60-70% of the concentration limit value, and the 1h wear rate is 25% of the concentration limit value, which can be adjusted according to actual conditions.

Claims

1. A method for formulating the required value of element content in aircraft engine lubricating oil spectrum detection, characterized in that: include: The required value of element content is determined based on the concentration alarm value, concentration limit value and 1h wear rate limit value.

2. The method for formulating the required value of the element content in the aircraft engine lubricating oil spectrum detection according to claim 1, characterized in that: The wear rate calculation formula for the 1h wear rate limit value is as follows: Wear rate = (C t -C t ′) / (TT′);

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