COMPONENT TESTING

Abstract

The present invention relates to a method for testing a component, in particular an aircraft engine, comprising the steps of: determining (S40) a value of a first toleranced parameter (A1; A2) of the component; determining (S50) a value of a second toleranced parameter (E1; ...; E4) of the component; and classifying (S70) the component in a predefined quality class if this value pair lies outside of a predefined tolerance range, the upper and/or lower limit (G) of which for the second parameter depends on the first parameter, in particular linearly, in at least one first permissible value range (Ta1,1) of the first parameter.

Claims

1-14. (canceled)

15. A method for testing a component, wherein the method comprises: determining (S40) a value of a first tolerated parameter (A1; A2) of the component; determining (S50) a value of a second tolerated parameter (E1;...;E4) of the component; and classifying (S70) the component in a specified quality class if the value pair is outside a specified tolerance range, the upper and/or lower limit (G) of which for the second parameter in at least one first permissible value range (Ta1,1) of the first parameter depend(s) on the first parameter.

16. The method of claim 15, wherein the upper and/or lower limit (G) of the tolerance range for the second parameter in the at least one first permissible value range (Ta1,1) of the first parameter depend(s) linearly on the first parameter.

17. The method of claim 15, wherein the upper and/or lower limit (G) of the tolerance range for the second parameter in at least one second permissible value range (Ta1,2) of the first parameter depend(s) on the first parameter in an opposing manner to the first permissible value range.

18. The method of claim 15, wherein the upper and/or lower limit (G) of the tolerance range for the second parameter in at least one second permissible value range (Ta1,2) of the first parameter depend(s) linearly on the first parameter in an opposing manner to the first permissible value range.

19. The method of claim 15, wherein the first permissible value range of the first parameter contains a minimum or maximum permissible value of the first parameter.

20. The method of claim 17, wherein the first permissible value range of the first parameter contains a minimum permissible value of the first parameter and the second permissible value range of the first parameter contains a maximum permissible value of the first parameter.

21. The method of claim 15, wherein the upper and/or lower limit of the tolerance range for the second parameter in at least one further permissible value range (Ta1,3) of the first parameter is/are independent of the first parameter.

22. The method of claim 15, wherein the method further comprises determining (S100) a value of at least a third tolerated parameter of the component; and classifying (S70) the component in the quality class if this value is outside a specified third tolerance field.

23. The method of claim 15, wherein the method comprises classifying (S70) the component in the quality class if the value of the first parameter is outside a specified maximum first tolerance field (Ta1); and/or classifying (S70) the component in the quality class if the value of the second parameter is outside a specified maximum second tolerance field (Te1).

24. The method of claim 15, wherein the component is rejected or reworked if it has been classified in the quality class.

25. The method of claim 15, wherein the component is an aircraft engine.

26. The method of claim 15, wherein the tolerance range is specified according to a method wherein a dependence of the upper and/or lower limit of the permissible tolerance field for the second parameter on the first parameter in the first and/or second permissible value range of the first parameter is specified (S25) on the basis of a property of the component type which depends on a combination of the first and second parameters.

27. A method for specifying a tolerance range for testing a component according to claim 15, wherein a dependence of the upper and/or lower limit of the permissible tolerance field for the second parameter on the first parameter in the first and/or second permissible value range of the first parameter is specified (S25) on the basis of a property of the component type which depends on a combination of the first and second parameters.

28. The method of claim 27, wherein the property of the component type is a structural-mechanical property.

29. The method of claim 28, wherein the property of the component type is a functionality.

30. The method of claim 15, wherein the component is a rotor blade or guide blade of a gas turbine and/or a dimensional tolerance is specified for the first parameter and/or a shape or positional tolerance for functional surfaces is specified for the second parameter.

31. The method of claim 30, wherein a length or a distance is specified for the first parameter and/or an unevenness of functional surfaces is specified for the second parameter.

32. The method of claim 15, wherein the specified tolerance range is indicated on a drawing of the component.

33. A system (100) for testing a component which is configured to perform a method according to claim 15 and/or comprises: components for determining a value of a first tolerated parameter of the component; components for determining a value of a second tolerated parameter of the component; and components for classifying the component in a specified quality class if this value pair is outside a specified tolerance range, the upper and/or lower limit of which for the second parameter in at least one first permissible value range of the first parameter depend(s) on the first parameter.

34. A computer program product, wherein the product comprises a program code for performing a method according to claim 15, stored on a computer-readable medium.

Description

[0054] Further advantageous developments of the present invention emerge from the subclaims and the following description of preferred embodiments. In this respect, in a partially schematic manner:

[0055] FIG. 1 shows a method according to one embodiment of the present invention;

[0056] FIG. 2 shows an excerpt of a component drawing used in the method;

[0057] FIG. 3 shows a specified tolerance range used in the method; and

[0058] FIG. 4 shows a system for performing the method.

[0059] FIG. 2 shows an excerpt of a component drawing for a blade having a fir-tree-like blade root for fastening the blade in a corresponding groove of a rotor or housing of a gas turbine.

[0060] The distances A1, A2 between functional surfaces of the blade root are tolerated and each form a first tolerated parameter of this component.

[0061] In addition, the evennesses or planarities E1, ..., E4 of these functional surfaces are tolerated and each form a second tolerated parameter of this component. In this case, the value of the corresponding evenness indicates, in a manner conventional in the art, the permissible plane distance between two parallel surfaces which define a gap-shaped tolerance zone between them in which the functional surface is intended to be located.

[0062] In a first step S10 (cf. FIG. 1), tolerances are specified for these component parameters and possibly further component parameters.

[0063] A second step S20 checks, for combinations of these component parameters, whether a strong deviation of the actual value of a parameter from its target or nominal dimension can be compensated for by a sufficiently small deviation of the actual value of the other parameter from its target or nominal dimension. Such combinations can be identified by the structural mechanics, for example, and appropriate dependences can be specified in each case therefor.

[0064] For such combinations (S20: “Y”), the combinations (A1, E1), (A1, E2), (A2, E3) and (A2, E4) in the exemplary embodiment, a corresponding tolerance range is specified in each case in a step S25, but not for the other combinations (S20: “N”), for example (A1, E3).

[0065] FIG. 3 shows, by way of example, the specified tolerance range for the first tolerated component parameter A1 and the second tolerated component parameter E1: the target or nominal dimensions for the two parameters are depicted using bold dashed lines and the maximum tolerance fields Ta1, Te1 for the two parameters are depicted using thin dash-dotted lines.

[0066] By virtue of the inequation indicated in the component drawing

[00001]${\text{a}}_{\text{c1}}\times \text{A1}-{\text{e}}_{\text{cl}}\times \text{E}1>{\text{c}}_{\text{11}}$

the upper limit G for the second parameter in a first permissible value range Ta1,1 of the first parameter, which contains the minimum permissible value 0.48 of the first parameter, depends linearly on the first parameter.

[0067] In a similar manner, the upper limit G for the second parameter in a second permissible value range Ta1,2 of the first parameter, which contains the maximum permissible value 0.55 of the first parameter, depends linearly on the first parameter, in an opposing manner, by virtue of the inequation indicated in the component drawing

[00002]${\text{a}}_{\text{d1}}\times \text{A}1-{\text{e}}_{\text{d1}}\times \text{E}1<{\text{d}}_{11}.$

[0068] In the further permissible value range Ta1,3 of the first parameter in between, the upper limit of the tolerance range for the second parameter is independent of the first parameter.

[0069] In a step S30, the corresponding inequations are indicated, together with the maximum permissible tolerance fields of the parameters A1, ..., E4, on the component drawing, as indicated in FIG. 2 for the maximum permissible tolerance fields of the parameters A1, ..., E4 and the above-described tolerance range for the combination (A1, E1).

[0070] In a step S40, the values of the first parameters A1, A2 are now measured for a specific component, and the values of the second parameters E1, ..., E4 are determined in a step S50 by means of measurement.

[0071] A step S60 then (in each case) checks whether the corresponding value pair for one of the (as yet unchecked) combinations, for which a tolerance range is specified, is outside the specified tolerance range.

[0072] If this is the case (S60: “Y”), the component is classified as a reject (FIG. 1: step S70).

[0073] Otherwise (S60: “N”), a check is carried out in order to determine whether a common tolerance range has been specified for further (as yet unchecked) combinations. If this is the case (S80: “Y”), step S60 is carried out again for these combinations.

[0074] Otherwise (S80: “N”), a check is carried out in order to determine whether a tolerance field which has not yet been checked has been specified for at least one third parameter.

[0075] If this is the case (S90: “Y”), the corresponding value is measured (S100) and a check is carried out in order to determine whether it is outside this specified tolerance field.

[0076] If this is the case (S110: “Y”), the component is likewise classified as a reject (S70).

[0077] Otherwise (S110: “N”), step S90 is carried out again.

[0078] If it is determined in said step that a tolerance field has not been specified for any (further or previously unchecked) third parameter (S90: “N”), the testing is ended (S120).

[0079] FIG. 4 shows a system for performing the method described above in an at least partially automated manner in the form of a computer 100 which is configured to classify the component as a reject or as good on the basis of input values for the first and second and possibly third parameters.

[0080] Although exemplary embodiments have been explained in the description above, it should be pointed out that a multiplicity of modifications are possible. In addition, it should be pointed out that the exemplary embodiments are merely examples which are not intended to restrict the scope of protection, the applications and the structure in any way. Rather, the description above provides a person skilled in the art with a guideline for implementing at least one exemplary embodiment, wherein various changes, in particular with regard to the function and arrangement of the component parts described, can be made without departing from the scope of protection as is clear from the claims and equivalent combinations of features.

TABLE-US-00001 List of reference signs 100 Computer (system) A1, A2 Distance between functional surfaces (first parameter) E1, ..., E4 Evenness of a functional surface (second parameter) G Upper limit Ta1 Maximum first tolerance field Ta1,1 First permissible value range of the first parameter Ta1,2 Second permissible value range of the first parameter Ta1,3 Further permissible value range of the first parameter Te1 Maximum second tolerance field