Claims
- 1. A method of predicting failure of a resistive element heater comprising the steps of:
compiling a historical database of design and construction variables that affect the life of a resistive element heater during service operation based on testing of a laboratory standard heater; assigning a ratiometric life factor to each variable within the representative set of design and construction variables for a given heater; creating a simplified model by factoring the individual ratiornetric life factors; normalizing actual service time on a given heater to an equivalent time on the laboratory standard heater; measuring the thermal profile of the resistive element heater by measuring the heater temperature at set time intervals and assigning each interval an element temperature related stress oxidation life factor based on the historical database and defining a cumulative life factor; mathematically manipulating the ratiometric life factor, the normalized service time, and the cumulative life factor during the measured time interval to determine the percentage of life used of the resistive element heater; and tracking the cumulative percentage of life used in the resistive element heater.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of application Ser. No. 09/316,803 filed May 21, 1999, now U.S. Pat. No. 6,336,083.
Divisions (1)
|
Number |
Date |
Country |
Parent |
09316803 |
May 1999 |
US |
Child |
09683447 |
Dec 2001 |
US |