Fuel and lubricating oil radiator pressure test verification method

Abstract

The present invention discloses a fuel and lubricating oil radiator pressure test verification method, which fully considers the maximum working pressure under extreme working conditions and the maximum possible pressure under failure state within the working envelope of the fuel and lubricating oil radiator, and fully considers the correction of pressure load by factors such as the working temperature of the test piece, the minimum performance of the material and process of the test piece, and any unfavorable geometric shape allowed by the model design; based on the oil side withstand pressure correction value and the fuel side withstand pressure correction value, the test piece is subjected to a withstand pressure test, and then based on the oil side burst pressure correction value and the fuel side burst pressure correction value, the test piece is subjected to a burst pressure test; based on the test results, it is judged whether the test piece meets the requirements, so that the fuel and lubricating oil radiator pressure test verification is in place; compared with the existing technology, the pressure value during the test verification is appropriate, and the factors considered are sufficient and comprehensive, which can ensure that the pressure test verification of the fuel and lubricating oil radiator is completely verified, has strong practicality, and is suitable for wide promotion and application.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel and lubricating oil radiator testing, and in particular to a fuel and lubricating oil radiator pressure test verification method. Background Art

[0002] In the chapter on engine static pressure parts in Article CCAR33.64 of the airworthiness regulations, strength requirements for engine static pressure parts under pressure loads are proposed. It is required that all static parts subjected to large gas or liquid pressure loads must be determined through tests, verified analysis, or a combination of the two methods to be able to maintain stability for one minute and will not experience permanent deformation beyond the use limit when subjected to the set pressure, or leakage that may cause harmful engine consequences; and will not rupture or explode when subjected to the set pressure. As one of the static pressure parts of an aircraft engine, the fuel and oil radiator also needs to undergo the above-mentioned test verification to demonstrate its compliance with airworthiness.

[0003] At present, the pressure test verification method for fuel and lubricating oil radiators is: the fuel side and the lubricating oil side are verified separately, the pressure value is selected as 2 times the rated working pressure (the pressure on the other side is 0), under room temperature conditions, the time lasts for 30 minutes, and visually visible lubricating oil leakage and unacceptable permanent deformation are not allowed.

[0004] However, the above method has the following problems:

[0005] 1) The pressure value was fixed and single, without considering the pressure (maximum working pressure) under the system's extreme environment (such as low temperature environment) and the pressure corresponding to component failure (maximum possible pressure). The pressure value during the test verification was too low;

[0006] 2) During the actual test, the impact of factors such as the operating temperature of the part, any other important static loads other than the pressure load, the minimum performance of the material and process of the part, and any unfavorable geometric shapes allowed by the model design on the pressure load were not considered. The considerations were not comprehensive and could not be fully verified. Summary of the Invention

[0007] The present invention provides a fuel and lubricating oil radiator pressure test verification method to solve the technical problems of the existing fuel and lubricating oil radiator pressure test verification method, such as small test verification pressure value and incomplete consideration of factors, resulting in inability to fully verify the condition.

[0008] According to one aspect of the present invention, a method for verifying a pressure test of a fuel and lubricating oil radiator is provided, comprising the following steps: S1: determining a test principle according to airworthiness test requirements, and installing a test piece based on the test principle; S2: determining the normal working pressure, maximum working pressure, and maximum possible pressure of the fuel side and the lubricating oil side of the test piece according to the working conditions of the test piece; S3: obtaining a pressure-resistant temperature load correction factor, a bursting pressure-resistant temperature load factor, a material correction factor, a process correction factor, and a geometric shape correction factor according to the yield strength and tensile strength of the test piece, so as to obtain an oil side pressure-resistant pressure correction value, a fuel side pressure-resistant pressure correction value, an oil side bursting pressure correction value, and a fuel side bursting pressure correction value of the test piece through a calculation formula; S4: performing a pressure-resistant pressure test on the test piece based on the oil side pressure-resistant pressure correction value and the fuel side pressure-resistant pressure correction value, and then performing a bursting pressure test on the test piece based on the oil side bursting pressure correction value and the fuel side bursting pressure correction value; S5: judging whether the test piece meets the requirements based on the test results.

[0009] As a further improvement of the above technical solution:

[0010] Furthermore, in step S3, the calculation formula of the oil side pressure correction value is as follows:

[0011] A1=MWP oil × 1.1 × αpp oil × Kpp process × Kpp material × T oil;

[0012] B1=NWP lubricating oil × 1.33 × αpp lubricating oil × Kpp process × Kpp material × T lubricating oil;

[0013] C1=(NWP oil + 0.035) × αpp oil × Kpp process × Kpp material × T oil;

[0014] D1=MAX(A1,B1,C1);

[0015] Among them, A1 is the proof pressure correction value of the first lubricating oil side, MWP lubricating oil is the maximum working pressure value of the lubricating oil side, αpp lubricating oil is the proof pressure temperature load correction factor of the lubricating oil side, Kpp process is the process correction factor, Kpp material is the material correction factor, T lubricating oil is the geometric shape correction factor of the lubricating oil side, B1 is the proof pressure correction value of the second lubricating oil side, NWP lubricating oil is the normal working pressure value of the lubricating oil side, C1 is the proof pressure correction value of the third lubricating oil side, and D1 is the proof pressure correction value of the lubricating oil side.

[0016] Furthermore, in step S3, the calculation formula of the fuel side pressure correction value is as follows:

[0017] A2=MWP fuel × 1.1 × αpp fuel × Kpp process × Kpp material × T fuel;

[0018] B2=NWP fuel × 1.33 × αpp fuel × Kpp process × Kpp material × T fuel;

[0019] C2=(NWP fuel + 0.035) × αpp fuel × Kpp process × Kpp material × T fuel;

[0020] D2=MAX(A2,B2,C2);

[0021] Wherein, A2 is the first fuel side proof pressure correction value, MWP fuel is the fuel side maximum working pressure value, αpp fuel is the fuel side proof pressure temperature load correction factor, T fuel is the fuel side geometry correction factor, B2 is the second fuel side proof pressure correction value, NWP fuel is the fuel side normal working pressure value, C2 is the third fuel side proof pressure correction value, and D2 is the fuel side proof pressure correction value.

[0022] Furthermore, in step S3, the calculation formula of the oil side burst pressure correction value is as follows:

[0023] A3=MPP oil × 1.15 × αup oil × Kup process × Kup material × T oil;

[0024] B3=MWP oil × 1.5 × αup oil × Kup process × Kup material × T oil;

[0025] C3=(MPP oil + 0.035) × αup oil × Kup process × Kup material × T oil;

[0026] D3=MAX(A3,B3,C3);

[0027] Among them, A3 is the burst pressure correction value of the first lubricating oil side, MPP lubricating oil is the maximum possible pressure value of the lubricating oil side, αup lubricating oil is the temperature load correction factor of the burst pressure on the lubricating oil side, Kup process is the process correction factor of the burst pressure on the lubricating oil side, Kup material is the material correction factor of the burst pressure on the lubricating oil side, B3 is the burst pressure correction value of the second lubricating oil side, C3 is the burst pressure correction value of the third lubricating oil side, and D3 is the burst pressure correction value of the lubricating oil side.

[0028] Furthermore, in step S3, the calculation formula of the fuel side burst pressure correction value is as follows:

[0029] A4=MPP fuel×1.15×αup fuel×Kup process×Kup material×T fuel;

[0030] B4=MWP fuel×1.5×αup fuel×Kup process×Kup material×T fuel;

[0031] C4=(MPP fuel + 0.035) × αup fuel × Kup process × Kup material × T fuel;

[0032] D4=MAX(A4,B4,C4);

[0033] Among them, A4 is the first fuel side burst pressure correction value, MPP fuel is the maximum possible fuel side pressure value, αup fuel is the fuel side burst pressure temperature load correction coefficient, B4 is the second fuel side burst pressure correction value, C4 is the third fuel side burst pressure correction value, and D4 is the fuel side burst pressure correction value.

[0034] Furthermore, the calculation formula of the pressure resistance temperature load correction coefficient is:

[0035]

[0036]

[0037] in, is the pressure value at room temperature, is the pressure value under working temperature conditions, is the yield strength of the material at room temperature, is the yield strength of the material under working temperature conditions, is the pressure-temperature load correction factor.

[0038] Furthermore, the calculation formula of the bursting pressure temperature load correction coefficient is:

[0039]

[0040]

[0041] in, is the tensile strength of the material at room temperature, is the tensile strength of the material under working temperature conditions, is the bursting pressure temperature load correction factor.

[0042] Furthermore, in step S4, the pressure resistance test of the test piece based on the oil side pressure resistance correction value and the fuel side pressure resistance correction value specifically includes the following steps: S40: Fill the fuel cavity and the oil cavity of the test piece with oil, connect the oil cavity inlet and the fuel cavity oil inlet of the test piece to the test bench, and seal the oil cavity outlet and the fuel cavity outlet; S41: pressurize the fuel cavity to the normal working pressure value, pressurize the oil cavity to the oil side pressure resistance correction value, and maintain the pressure for at least one minute after stabilizing. During the test, record the pressure holding time and observe whether there is oil leakage; S42: After the test, remove the oil cavity pressure and the fuel cavity pressure; S43: pressurize the oil cavity to the normal working pressure value, pressurize the fuel cavity to the fuel side pressure resistance correction value, and maintain the pressure for at least one minute after stabilizing. During the test, record the pressure holding time and observe whether there is oil leakage; S44: After the test, first remove the test piece from the test bench, then clean and air-dry the test piece, and finally perform a functional performance inspection on the test piece.

[0043] Furthermore, in step S4, the bursting pressure test of the test piece based on the oil side bursting pressure correction value and the fuel side bursting pressure correction value specifically includes the following steps: S45: the test piece is connected to the test bench, the fuel chamber and the oil chamber of the test piece are filled with oil, the oil chamber inlet and the fuel chamber oil inlet of the test piece are connected to the test bench, and the oil chamber outlet and the fuel chamber outlet are sealed; S46: the fuel chamber is pressurized to the normal working pressure value, the oil chamber is pressurized to the oil side bursting pressure correction value, and the pressure is maintained for at least one minute after stabilizing. During the test, the pressure holding time is recorded and the test piece structure is observed to see if it bursts; S47: after the test, the oil chamber pressure and the fuel chamber pressure are released; S48: the oil chamber is pressurized to the normal working pressure value, the fuel chamber is pressurized to the fuel side bursting pressure correction value, and the pressure is maintained for at least one minute after stabilizing. During the test, the pressure holding time is recorded and the test piece structure is observed to see if it bursts; S49: after the test, the test piece is first removed from the test bench and the appearance of the test piece is inspected.

[0044] Furthermore, in step S5, the basis for judging compliance with the requirements is:

[0045] After the pressure test, the test piece should not show any visible deformation, and the radiator meets the airtightness test requirements;

[0046] After the burst pressure test, the test piece was structurally intact, with no explosion or rupture, and no leakage due to pressure chamber failure.

[0047] The present invention has the following beneficial effects:

[0048] The fuel and lubricating oil radiator pressure test verification method of the present invention determines the test principle according to the airworthiness test requirements and installs the test piece based on the test principle. Then, according to the working conditions of the test piece, the normal working pressure, maximum working pressure and maximum possible pressure of the fuel side and the lubricating oil side of the test piece are determined respectively, so as to fully consider the maximum working pressure under the extreme working conditions and the maximum possible pressure under the failure state within the working envelope of the fuel and lubricating oil radiator; then, according to the yield strength and tensile strength of the test piece, the pressure-temperature load correction factor, the bursting pressure-temperature load factor, the material correction factor, the process correction factor, and the geometric shape correction factor are obtained, so as to calculate the oil side pressure-temperature correction value, the fuel side pressure-temperature correction value, the oil side bursting pressure correction value and the fuel side bursting pressure correction value of the test piece through the calculation formula, so as to obtain the pressure-temperature correction value of the fuel side, the pressure-temperature correction value, the bursting pressure correction value of the lubricating oil side and the fuel side bursting pressure correction value of the test piece. In the case that the fuel and lubricating oil radiator has no other important static loads except the pressure load, the pressure load is corrected by fully considering factors such as the operating temperature of the test piece, the minimum performance of the material and process of the test piece, and any unfavorable geometric shapes allowed by the model design; then, a pressure test is performed on the test piece based on the oil side pressure resistance correction value and the fuel side pressure resistance correction value, and then a bursting pressure test is performed on the test piece based on the oil side bursting pressure correction value and the fuel side bursting pressure correction value; finally, based on the test results, it is judged whether the test piece meets the requirements, so that the fuel and lubricating oil radiator pressure test verification is in place; compared with the existing technology, this scheme has appropriate pressure values ​​during test verification and fully and comprehensively considers factors, which can ensure that the pressure test verification of the fuel and lubricating oil radiator is completely verified, has strong practicality, and is suitable for wide promotion and application.

[0049] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0051] Figure 1 This is a flowchart of the steps of the fuel and lubricating oil radiator pressure test verification method according to the preferred embodiment of the present invention;

[0052] Figure 2 It is a test principle diagram of a fuel oil radiator pressure test verification method according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0053] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0054] like Figure 1 and Figure 2 As shown, the fuel and oil radiator pressure test verification method of this embodiment includes the following steps: S1: determining the test principle according to the airworthiness test requirements and installing the test piece based on the test principle; S2: determining the normal working pressure, maximum working pressure and maximum possible pressure of the fuel side and the oil side of the test piece according to the working conditions of the test piece; S3: obtaining the pressure-temperature load correction factor, bursting pressure-temperature load factor, material correction factor, process correction factor, and geometric shape correction factor according to the yield strength and tensile strength of the test piece, so as to calculate the oil side pressure correction value, fuel side pressure correction value, oil side bursting pressure correction value and fuel side bursting pressure correction value of the test piece through a calculation formula; S4: performing a pressure test on the test piece based on the oil side pressure correction value and the fuel side pressure correction value, and then performing a bursting pressure test on the test piece based on the oil side bursting pressure correction value and the fuel side bursting pressure correction value; S5: judging whether the test piece meets the requirements based on the test results.

[0055] like Figure 1 and Figure 2 As shown, specifically, the fuel and lubricating oil radiator pressure test verification method of the present invention determines the test principle according to the airworthiness test requirements and installs the test piece based on the test principle. Then, according to the working condition of the test piece, the normal working pressure, maximum working pressure and maximum possible pressure of the fuel side and the lubricating oil side of the test piece are determined respectively, so as to fully consider the maximum working pressure under the extreme working condition and the maximum possible pressure under the failure state within the working envelope of the fuel and lubricating oil radiator; then, according to the yield strength and tensile strength of the test piece, the pressure-temperature load correction factor, the bursting pressure-temperature load factor, the material correction factor, the process correction factor, and the geometric shape correction factor are obtained, so as to calculate the oil side pressure-proof pressure correction value, the fuel side pressure-proof pressure correction value, the oil side bursting pressure correction value and the fuel side bursting pressure correction value of the test piece through the calculation formula. The invention provides a method for correcting the pressure load by taking into full account the operating temperature of the test piece, the minimum performance of the material and process of the test piece, and any unfavorable geometric shapes allowed by the model design, under the condition that the fuel and lubricating oil radiator has no other important static loads except the pressure load; then, a pressure test is performed on the test piece based on the oil side pressure proof pressure correction value and the fuel side pressure proof pressure correction value, and then a bursting pressure test is performed on the test piece based on the oil side bursting pressure correction value and the fuel side bursting pressure correction value; finally, whether the test piece meets the requirements is judged based on the test results, so that the pressure test verification of the fuel and lubricating oil radiator is in place; compared with the existing technology, the pressure value of this scheme is appropriate during the test verification, and the factors considered are sufficient and comprehensive, which can ensure that the pressure test verification of the fuel and lubricating oil radiator is fully verified, has strong practicality, and is suitable for wide promotion and application.

[0056] like Figure 2As shown, it should be understood that the test principle is as follows: the test piece of the fuel and oil radiator is installed on the test fixture, the oil side and fuel side outlets of the test piece are blocked by stop valve 1 and stop valve 2 respectively, the pressure source of the test piece applies pressure to the oil side and fuel side respectively, the pressure of the oil side is regulated by pressure regulating valve 1, and the pressure of the fuel side is regulated by pressure regulating valve 2, the oil pressure at the oil side inlet of the test piece is measured by pressure gauge 1, and the oil pressure at the fuel side inlet of the test piece is measured by pressure gauge 2.

[0057] In this embodiment, in step S3, the calculation formula of the oil side pressure correction value is as follows:

[0058] A1=MWP oil × 1.1 × αpp oil × Kpp process × Kpp material × T oil;

[0059] B1=NWP lubricating oil × 1.33 × αpp lubricating oil × Kpp process × Kpp material × T lubricating oil;

[0060] C1=(NWP oil + 0.035) × αpp oil × Kpp process × Kpp material × T oil;

[0061] D1=MAX(A1,B1,C1);

[0062] Among them, A1 is the proof pressure correction value of the first lubricating oil side, MWP lubricating oil is the maximum working pressure value of the lubricating oil side, αpp lubricating oil is the proof pressure temperature load correction factor of the lubricating oil side, Kpp process is the process correction factor, Kpp material is the material correction factor, T lubricating oil is the geometric shape correction factor of the lubricating oil side, B1 is the proof pressure correction value of the second lubricating oil side, NWP lubricating oil is the normal working pressure value of the lubricating oil side, C1 is the proof pressure correction value of the third lubricating oil side, and D1 is the proof pressure correction value of the lubricating oil side.

[0063] Specifically, in the above calculation formula, the three set pressures of 1.1 times the maximum working pressure value MWP of the lubricating oil side, 1.33 times the normal working pressure value NWP of the lubricating oil side, and 35kpa greater than the normal working pressure value NWP of the lubricating oil side are corrected respectively through the oil side pressure-temperature load correction coefficient αppoil, the process correction coefficient Kppprocess, the material correction coefficient Kppmaterial and the oil side geometry correction coefficient Toil, to ensure that all factors are considered fully and comprehensively, so as to obtain the first oil side pressure-temperature correction value A1, the second oil side pressure-temperature correction value B1 and the third oil side pressure-temperature correction value C1, and then select the maximum value of A1, B1 and C1 as the oil side pressure-temperature correction value D1 to ensure that the pressure value is appropriate during the actual test verification, so that the oil side pressure-temperature correction value of the fuel and lubricating oil radiator is in place.

[0064] It should be understood that a typical fuel oil radiator usually adopts a welding process. Therefore, the process correction factor Kppprocess is the ratio of the yield strength of the fuel oil radiator after welding to the yield strength of the base material.

[0065] It should be understood that a typical oil radiator housing is usually a casting. Therefore, the material correction factor Kpp is the ratio of the yield strength actually measured for the oil radiator casting to the minimum yield strength specified in the oil radiator casting standard.

[0066] It should be understood that the geometric feature that affects the bearing pressure on the oil side of the fuel and lubricating oil radiator is the wall thickness. Therefore, the oil side geometry correction factor Toil is the ratio of the actual measured wall thickness of the oil side of the fuel and lubricating oil radiator to the theoretical minimum wall thickness of the oil side of the fuel and lubricating oil radiator.

[0067] It should be understood that the geometry correction factor refers to any unfavorable geometry correction factor allowed by the model design.

[0068] In this embodiment, in step S3, the calculation formula of the fuel side pressure correction value is as follows:

[0069] A2=MWP fuel × 1.1 × αpp fuel × Kpp process × Kpp material × T fuel;

[0070] B2=NWP fuel × 1.33 × αpp fuel × Kpp process × Kpp material × T fuel;

[0071] C2=(NWP fuel + 0.035) × αpp fuel × Kpp process × Kpp material × T fuel;

[0072] D2=MAX(A2,B2,C2);

[0073] Wherein, A2 is the first fuel side proof pressure correction value, MWP fuel is the fuel side maximum working pressure value, αpp fuel is the fuel side proof pressure temperature load correction factor, T fuel is the fuel side geometry correction factor, B2 is the second fuel side proof pressure correction value, NWP fuel is the fuel side normal working pressure value, C2 is the third fuel side proof pressure correction value, and D2 is the fuel side proof pressure correction value.

[0074] Specifically, in the above calculation formula, the three set pressures of 1.1 times the fuel side maximum working pressure value MWP fuel, 1.33 times the fuel side normal working pressure value NWP fuel, and 35 kPa greater than the fuel side normal working pressure value NWP fuel are corrected respectively by the fuel side pressure-temperature load correction coefficient αpp fuel, the process correction coefficient Kpp process, the material correction coefficient Kpp material, and the fuel side geometry correction coefficient T fuel, to ensure that all factors are fully considered, so as to obtain the first fuel side pressure resistance correction value A2, the second fuel side pressure resistance correction value B2, and the third fuel side pressure resistance correction value C2. The maximum value of A2, B2 and C2 is then selected as the fuel side pressure resistance correction value D2 to ensure that the pressure value is appropriate during the actual test verification, so that the fuel side pressure resistance test verification of the lubricating oil radiator is in place.

[0075] It should be understood that the geometric characteristic that affects the bearing pressure on the fuel side of the fuel and lubricating oil radiator is the wall thickness. Therefore, the fuel side geometry correction factor Tfuel is the ratio of the measured fuel side wall thickness of the fuel and lubricating oil radiator to the theoretical minimum fuel side wall thickness of the fuel and lubricating oil radiator.

[0076] In this embodiment, in step S3, the calculation formula of the oil side burst pressure correction value is as follows:

[0077] A3=MPP oil × 1.15 × αup oil × Kup process × Kup material × T oil;

[0078] B3=MWP oil × 1.5 × αup oil × Kup process × Kup material × T oil;

[0079] C3=(MPP oil + 0.035) × αup oil × Kup process × Kup material × T oil;

[0080] D3=MAX(A3,B3,C3);

[0081] Among them, A3 is the burst pressure correction value of the first lubricating oil side, MPP lubricating oil is the maximum possible pressure value of the lubricating oil side, αup lubricating oil is the temperature load correction factor of the burst pressure on the lubricating oil side, Kup process is the process correction factor of the burst pressure on the lubricating oil side, Kup material is the material correction factor of the burst pressure on the lubricating oil side, B3 is the burst pressure correction value of the second lubricating oil side, C3 is the burst pressure correction value of the third lubricating oil side, and D3 is the burst pressure correction value of the lubricating oil side.

[0082] Specifically, in the above calculation formula, the three set pressures of 1.15 times the maximum possible pressure value MPP oil on the lubricating oil side, 1.5 times the maximum working pressure value MWP oil on the lubricating oil side and 35 kpa greater than the maximum working pressure value MWP oil on the lubricating oil side are corrected respectively through the oil side bursting pressure temperature load correction coefficient αup oil, the process correction coefficient Kup process, the material correction coefficient Kup material and the oil side geometry correction coefficient T oil, to ensure that all factors are considered fully and comprehensively, so as to obtain the first oil side bursting pressure correction value A3, the second oil side bursting pressure correction value B3 and the third oil side bursting pressure correction value C3, and then select the maximum value among A3, B3 and C3 as the oil side bursting pressure correction value D3 to ensure that the pressure value is appropriate during the actual test verification, so that the oil side bursting pressure test verification of the fuel and lubricating oil radiator is in place.

[0083] It should be understood that a typical fuel oil radiator usually adopts a welding process. Therefore, the process correction factor Kup process is the ratio of the yield strength of the fuel oil radiator after welding to the yield strength of the base material.

[0084] It should be understood that a typical oil radiator housing is usually a casting. Therefore, the material correction factor Kup material is the ratio of the actual yield strength of the oil radiator casting to the minimum yield strength specified in the oil radiator casting standard.

[0085] In this embodiment, in step S3, the calculation formula of the fuel side burst pressure correction value is as follows:

[0086] A4=MPP fuel×1.15×αup fuel×Kup process×Kup material×T fuel;

[0087] B4=MWP fuel×1.5×αup fuel×Kup process×Kup material×T fuel;

[0088] C4=(MPP fuel + 0.035) × αup fuel × Kup process × Kup material × T fuel;

[0089] D4=MAX(A4,B4,C4);

[0090] Among them, A4 is the first fuel side burst pressure correction value, MPP fuel is the maximum possible fuel side pressure value, αup fuel is the fuel side burst pressure temperature load correction coefficient, B4 is the second fuel side burst pressure correction value, C4 is the third fuel side burst pressure correction value, and D4 is the fuel side burst pressure correction value.

[0091] Specifically, in the above calculation formula, the three set pressures of 1.15 times the maximum possible fuel side pressure value MPPfuel, 1.5 times the maximum fuel side working pressure value MWPfuel, and 35 kPa greater than the maximum fuel side working pressure value MWPfuel are corrected respectively using the fuel side burst pressure temperature load correction coefficient αupfuel, the process correction coefficient Kupprocess, the material correction coefficient Kupmaterial, and the fuel side geometry correction coefficient Tfuel. This ensures that all factors are fully considered to obtain a first fuel side burst pressure correction value A4, a second fuel side burst pressure correction value B4, and a third fuel side burst pressure correction value C4. The maximum value among A4, B4, and C4 is then selected as the fuel side burst pressure correction value D4 to ensure that the pressure value is appropriate during the actual test verification, so that the fuel side burst pressure test verification of the lubricating oil radiator is in place.

[0092] In this embodiment, the calculation formula of the pressure resistance temperature load correction coefficient is:

[0093]

[0094]

[0095] in, is the pressure value at room temperature, is the pressure value under working temperature conditions, is the yield strength of the material at room temperature, is the yield strength of the material under working temperature conditions, is the pressure-temperature load correction factor.

[0096] Specifically, it can be seen from the above calculation formula that the pressure-temperature load correction coefficient can be obtained by converting the yield strength of the fuel and lubricating oil radiator material at different temperatures, that is, the pressure-temperature load correction coefficient on the lubricating oil side is the ratio of the yield strength of the lubricating oil side material of the fuel and lubricating oil radiator under working temperature conditions to the yield strength of the lubricating oil side material of the fuel and lubricating oil radiator under room temperature conditions; that is, the pressure-temperature load correction coefficient on the fuel side is the ratio of the yield strength of the fuel side material of the fuel and lubricating oil radiator under working temperature conditions to the yield strength of the fuel side material of the fuel and lubricating oil radiator under room temperature conditions.

[0097] It should be understood that the operating temperature refers to the temperature of the medium in the fuel and oil radiator during actual operation.

[0098] In this embodiment, the calculation formula of the blasting pressure temperature load correction coefficient is:

[0099]

[0100]

[0101] in, is the tensile strength of the material at room temperature, is the tensile strength of the material under working temperature conditions, is the bursting pressure temperature load correction factor.

[0102] Specifically, it can be seen from the above calculation formula that the bursting pressure temperature load correction coefficient can be obtained by converting the tensile strength of the fuel and lubricating oil radiator material at different temperatures, that is, the bursting pressure temperature load correction coefficient on the lubricating oil side is the ratio of the tensile strength of the lubricating oil side material of the fuel and lubricating oil radiator under working temperature conditions to the tensile strength of the lubricating oil side material of the fuel and lubricating oil radiator under room temperature conditions; that is, the bursting pressure temperature load correction coefficient on the fuel side is the ratio of the tensile strength of the fuel side material of the fuel and lubricating oil radiator under working temperature conditions to the tensile strength of the fuel side material of the fuel and lubricating oil radiator under room temperature conditions.

[0103] In this embodiment, in step S4, the pressure test of the test piece based on the oil side pressure resistance correction value and the fuel side pressure resistance correction value specifically includes the following steps: S40: Fill the fuel cavity and the oil cavity of the test piece with oil, connect the oil cavity inlet and the fuel cavity oil inlet of the test piece to the test bench, and seal the oil cavity outlet and the fuel cavity outlet; S41: pressurize the fuel cavity to the normal working pressure value, pressurize the oil cavity to the oil side pressure resistance correction value, and maintain the pressure for at least one minute after stabilizing. During the test, record the pressure holding time and observe whether there is oil leakage; S42: After the test, remove the oil cavity pressure and the fuel cavity pressure; S43: pressurize the oil cavity to the normal working pressure value, pressurize the fuel cavity to the fuel side pressure resistance correction value, and maintain the pressure for at least one minute after stabilizing. During the test, record the pressure holding time and observe whether there is oil leakage; S44: After the test, first remove the test piece from the test bench, then clean and air-dry the test piece, and finally perform a functional performance inspection on the test piece.

[0104] Specifically, through the above steps, the pressure resistance test of the oil side and the fuel side of the fuel and lubricating oil radiator can be completed respectively, so as to provide test results for verifying whether the fuel and lubricating oil radiator meets the airworthiness requirements.

[0105] Furthermore, in this embodiment, in step S4, the bursting pressure test of the test piece based on the oil side bursting pressure correction value and the fuel side bursting pressure correction value specifically includes the following steps: S45: the test piece is connected to the test bench, the fuel chamber and the oil chamber of the test piece are filled with oil, the oil chamber inlet and the fuel chamber oil inlet of the test piece are connected to the test bench, and the oil chamber outlet and the fuel chamber outlet are sealed; S46: the fuel chamber is pressurized to the normal working pressure value, the oil chamber is pressurized to the oil side bursting pressure correction value, and the pressure is maintained for at least one minute after stabilizing. During the test, the pressure holding time is recorded and the test piece structure is observed to see if it bursts; S47: after the test is completed, the oil chamber pressure and the fuel chamber pressure are released; S48: the oil chamber is pressurized to the normal working pressure value, the fuel chamber is pressurized to the fuel side bursting pressure correction value, and the pressure is maintained for at least one minute after stabilizing. During the test, the pressure holding time is recorded and the test piece structure is observed to see if it bursts; S49: after the test is completed, the test piece is first removed from the test bench, and then the test piece is visually inspected.

[0106] Specifically, through the above steps, the bursting pressure tests on the oil side and the fuel side of the fuel and lubricating oil radiator can be completed respectively, so as to provide test results for verifying whether the fuel and lubricating oil radiator meets the airworthiness requirements.

[0107] It should be understood that the appearance inspection refers to checking whether the test piece has burst or cracked.

[0108] Optionally, the specific steps of cleaning and air-drying the test piece are: after pouring out the oil in the inner cavity of the test piece, cleaning the inner and outer surfaces of the test piece with gasoline, and drying it with low-pressure air.

[0109] It should be understood that the purpose of the burst pressure test is to verify that the fuel and oil radiator will not rupture or explode when operating under extreme conditions, and will not affect the safety of the system and engine operation.

[0110] In this embodiment, in step S5, the basis for determining compliance with the requirements is:

[0111] After the pressure test, the test piece should not show any visible deformation, and the radiator meets the airtightness test requirements;

[0112] After the burst pressure test, the test piece was structurally intact, with no explosion or rupture, and no leakage due to pressure chamber failure.

[0113] Specifically, the above-mentioned judgment basis can be used to determine whether the test piece of the fuel and lubricating oil radiator meets the airworthiness requirements, thereby ensuring that the fuel and lubricating oil radiator pressure test verification is in place.

[0114] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

[0115] This article uses specific examples to illustrate the principles and implementation methods of this application. The above examples are only used to help understand the method and core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of this application, they can make several improvements, modifications or changes, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the concept and technical solution of this application to other occasions without improvement, should be regarded as the protection of this application.

Claims

1. A fuel oil radiator pressure test verification method, characterized in that: The following steps are involved: S1: Determine the test principle according to the airworthiness test requirements and install the test piece based on the test principle; S2: Determine the normal operating pressure, maximum operating pressure and maximum possible pressure on the fuel side and oil side of the test piece according to the working conditions of the test piece; S3: Based on the yield strength and tensile strength of the test piece, obtain the pressure-temperature load correction factor, the bursting pressure-temperature load factor, the material correction factor, the process correction factor, and the geometric shape correction factor, so as to calculate the oil side pressure correction value, the fuel side pressure correction value, the oil side bursting pressure correction value, and the fuel side bursting pressure correction value of the test piece through a calculation formula; S4: Perform a pressure test on the test piece based on the oil side proof pressure correction value and the fuel side proof pressure correction value, and then perform a burst pressure test on the test piece based on the oil side burst pressure correction value and the fuel side burst pressure correction value; S5: Determine whether the test piece meets the requirements based on the test results; In step S3, the calculation formula of the oil side burst pressure correction value is as follows: A3 = MPP oil × 1.15 × αup oil × Kup process × Kup material × T oil; B3 = MWP oil × 1.5 × αup oil × Kup process × Kup material × T oil; C3 = (MPP oil + 0.035) × αup oil × Kup process × Kup material × T oil; D3=MAX(A3,B3,C3); Wherein, A3 is the first oil side burst pressure correction value, MPP oil is the maximum possible pressure value of the oil side, αup oil is the oil side burst pressure temperature load correction factor, Kup process is the oil side burst pressure process correction factor, Kup material is the oil side burst pressure material correction factor, T oil is the oil side geometry correction factor, B3 is the second oil side burst pressure correction value, MWP oil is the maximum working pressure value of the oil side, C3 is the third oil side burst pressure correction value, and D3 is the oil side burst pressure correction value; The calculation formula of the burst pressure temperature load correction factor is: Among them, σ b (RT) is the tensile strength of the material at room temperature, σ b (WT) is the tensile strength of the material under working temperature conditions, α up is the bursting pressure temperature load correction factor.

2. The fuel and lubricating oil radiator pressure test verification method according to claim 1, characterized in that: In step S3, the calculation formula of the oil side pressure correction value is as follows: A1 = MWP oil × 1.1 × αpp oil × Kpp process × Kpp material × T oil; B1 = NWP oil × 1.33 × αpp oil × Kpp process × Kpp material × T oil; C1 = (NWP oil + 0.035) × αpp oil × Kpp process × Kpp material × T oil; D1=MAX(A1,B1,C1); Among them, A1 is the proof pressure correction value of the first lubricating oil side, αpp lubricating oil is the proof pressure temperature load correction factor of the lubricating oil side, Kpp process is the process correction factor, Kpp material is the material correction factor, B1 is the proof pressure correction value of the second lubricating oil side, NWP lubricating oil is the normal working pressure value of the lubricating oil side, C1 is the proof pressure correction value of the third lubricating oil side, and D1 is the proof pressure correction value of the lubricating oil side.

3. The fuel and lubricating oil radiator pressure test verification method according to claim 2, characterized in that: In step S3, the calculation formula of the fuel side withstand pressure correction value is as follows: A2 = MWP fuel × 1.1 × αpp fuel × Kpp process × Kpp material × T fuel; B2 = NWP fuel × 1.33 × αpp fuel × Kpp process × Kpp material × T fuel; C2 = (NWP fuel + 0.035) × αpp fuel × Kpp process × Kpp material × T fuel; D2=MAX(A2,B2,C2); Wherein, A2 is the first fuel side proof pressure correction value, MWP fuel is the fuel side maximum working pressure value, αpp fuel is the fuel side proof pressure temperature load correction factor, T fuel is the fuel side geometry correction factor, B2 is the second fuel side proof pressure correction value, NWP fuel is the fuel side normal working pressure value, C2 is the third fuel side proof pressure correction value, and D2 is the fuel side proof pressure correction value.

4. The fuel and lubricating oil radiator pressure test verification method according to claim 3, characterized in that: In step S3, the calculation formula of the fuel side burst pressure correction value is as follows: A4=MPP fuel×1.15×αup fuel×Kup process×Kup material×T fuel; B4 = MWP fuel × 1.5 × αup fuel × Kup process × Kup material × T fuel; C4=(MPP fuel + 0.035)×αup fuel×Kup process×Kup material×T fuel; D4=MAX(A4,B4,C4); Among them, A4 is the first fuel side burst pressure correction value, MPP fuel is the maximum possible fuel side pressure value, αup fuel is the fuel side burst pressure temperature load correction coefficient, B4 is the second fuel side burst pressure correction value, C4 is the third fuel side burst pressure correction value, and D4 is the fuel side burst pressure correction value.

5. The fuel and lubricating oil radiator pressure test verification method according to any one of claims 1 to 4, characterized in that: The calculation formula for the pressure resistance temperature load correction factor is: Among them, P RT is the pressure value at room temperature, P WT is the pressure value under working temperature conditions, σ 0.2 (RT) is the yield strength of the material at room temperature, σ 0.2 (WT) is the yield strength of the material under working temperature conditions, α pp is the pressure-temperature load correction factor.

6. The fuel and lubricating oil radiator pressure test verification method according to any one of claims 1 to 4, characterized in that: In step S4, performing a pressure test on the test piece based on the oil side pressure correction value and the fuel side pressure correction value specifically includes the following steps: S40: Filling the fuel cavity and the lubricating oil cavity of the test piece with oil, connecting the lubricating oil cavity inlet and the fuel cavity oil inlet of the test piece to the test bench, and sealing the lubricating oil cavity outlet and the fuel cavity outlet; S41: Pressurize the fuel chamber to the normal operating pressure and the oil chamber to the corrected oil side pressure. Maintain the pressure for at least one minute after stabilization. During the test, record the pressure holding time and observe for any oil leakage. S42: After the test, release the oil chamber pressure and the fuel chamber pressure; S43: Pressurize the oil chamber to the normal operating pressure and the fuel chamber to the corrected fuel side pressure. Maintain the pressure for at least one minute after stabilization. During the test, record the pressure holding time and observe for any oil leakage. S44: After the test, first remove the test piece from the test bench, then clean and air-dry the test piece, and finally check the functional performance of the test piece.

7. The fuel and lubricating oil radiator pressure test verification method according to claim 6, characterized in that: In step S4, performing a burst pressure test on the test piece based on the oil side burst pressure correction value and the fuel side burst pressure correction value specifically includes the following steps: S45: Connect the test piece to the test bench, fill the fuel cavity and lubricating oil cavity of the test piece with oil, connect the lubricating oil cavity inlet and the fuel cavity oil inlet of the test piece to the test bench, and seal the lubricating oil cavity outlet and the fuel cavity outlet; S46: Pressurize the fuel chamber to the normal operating pressure value and the oil chamber to the oil side burst pressure correction value. Maintain the pressure for at least one minute after stabilization. During the test, record the pressure holding time and observe whether the test piece structure bursts. S47: After the test, release the oil chamber pressure and the fuel chamber pressure; S48: Pressurize the oil chamber to the normal operating pressure and the fuel chamber to the fuel side burst pressure correction value. Maintain the pressure for at least one minute after stabilization. During the test, record the pressure holding time and observe whether the test piece structure bursts. S49: After the test, first remove the test piece from the test bench and then perform a visual inspection on the test piece.

8. The fuel and lubricating oil radiator pressure test verification method according to any one of claims 1 to 4, characterized in that: In step S5, the criteria for determining compliance are: After the pressure test, the test piece should not show any visible deformation, and the radiator meets the airtightness test requirements; After the burst pressure test, the test piece was structurally intact, with no explosion or rupture, and no leakage due to pressure chamber failure.

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