Stress monitoring during the operation of a component
A method for determining operating stress on a component during operation includes recording measured values for predefined measurement variables not equal to the operating stress on the component to be determined, during operation of the component for at least n≥2 predefined different operating modes, determining m≥2 and m≤n effect operands W 1 to W m , in dependence on the measured values for each operating mode, recording a measured value of operating stress after operating the component for n operating modes, and setting up and solving an equation system having n equations to obtain m weighting factors a 1 to a m weighting the m effect operands. A sum of weighted effect operands for each operating mode is equal to the measured value of the operating stress recorded for the operating mode. A calculation rule determining the operating stress during operation of the component uses the weighting factors.
1. A method for determining an operating stress of a component during operation of the component comprises the following steps:
a. recording measured values for predefined measurement variables during operation of the component in an adjustment phase for at least n different predefined operating modes, where n≥2, the measurement variables not being equal to the operating stress of the component to be determined;
b. determining m effect operands W 1 to W m in predefined dependence on the measured values for each of the n operating modes, where m≥2 and m≤n;
c. recording, during the adjustment phase, a measured value of the operating stress after operation of the component for each of the n operating modes;
d. setting up and solving a system of equations having n equations to obtain m weighting factors a 1 to a m weighting the m effect operands W 1 to W m , a sum of the weighted effect operands for each operating mode being equal to the measured value of the operating stress recorded for the corresponding operating mode; and
e. providing a calculation rule to an evaluation unit and in the evaluation unit, determining the operating stress by using the obtained weighting factors in the calculating rule during operation of the component in an operating phase;
wherein the n operating modes comprise at least:
a first operating mode including normal decelerations from predefined speeds on approaching a stop;
a second operating mode including emergency or rapid decelerations from high speeds; and
a third operating mode including emergency or rapid decelerations from low speeds;
wherein the component is a brake lining of a rail vehicle;
wherein the predefined measurement variables are at least one of time or braking distance or pressure in a brake cylinder of a compressed air brake of the rail vehicle; and
further comprising obtaining three effect operands including:
a first effect operand obtained from an integral of the square of the pressure in the brake cylinder of the compressed air brake of the rail vehicle over the braking distance of the rail vehicle,
a second effect operand obtained from an integral of a multiplication of a speed of the rail vehicle and the pressure in the brake cylinder of the compressed air brake of the rail vehicle over the braking distance of the rail vehicle, and
a third effect operand obtained from an integral of the pressure in the brake cylinder of the compressed air brake of the rail vehicle over the braking distance of the rail vehicle.
2. The method according to claim 1 , which further comprises the following steps following step e:
f. recording measured values for the predefined measurement variables during operation of the component in the operating phase, the measurement variables not being equal to the operating stress of the component to be determined;
g. determining the effect operands W 1 to W m in predefined dependence on the measured values; and
h. determining the operating stress of the component during operation of the component by using the calculation rule with the obtained weighting factors.
3. The method according to claim 2 , which further comprises, before step f, exchanging the component with a component from a common group of identical components.
4. The method according to claim 2 , which further comprises outputting the operating stress of the component determined in step h during operation of the component.
5. The method according to claim 1 , which further comprises solving the system of equations set up in step d by using equivalence transformations.
6. The method according to claim 1 , which further comprises determining the effect operands by using mathematical operations exclusively using the recorded measured values for the predefined measurement variables and predefined constants as operands.
7. At least one non-transitory computer-readable medium having a computer program product stored thereon, the computer program product, when executed by a processor, performing the steps of claim 1 .