Methods and apparatus for estimating a condition of a seal of a rotary valve

Abstract

Methods and apparatus for estimating a condition of a seal of a rotary valve are disclosed. An example apparatus includes a housing and a processor positioned within the housing. The processor is to determine a seal wearing cycle of a flow control member of a rotary valve, the seal wearing cycle includes movement of the flow control member between a first position in contact with a seal and a second position. The processor is to determine a torque of an actuator operating the flow control member for the seal wearing cycle and estimate a condition of the seal based on the torque.

What is claimed is: 
     
         1 . An apparatus, comprising:
 a housing; and   a processor positioned within the housing, the processor to:
 determine a seal wearing cycle of a flow control member of a rotary valve, the seal wearing cycle comprising movement of the flow control member between a first position in contact with a seal and a second position; 
 determine a torque of an actuator operating the flow control member for the seal wearing cycle; and 
 estimate a condition of the seal based on the torque. 
   
     
     
         2 . The apparatus of  claim 1 , wherein the second position is a position of the flow control member where the flow control member initially engages or disengages the seal. 
     
     
         3 . The apparatus of  claim 1 , wherein the processor is to estimate the condition of the seal by calculating a value based on the torque and a set value. 
     
     
         4 . The apparatus of  claim 3 , wherein calculating the value comprises calculating a ratio using the torque and the set value. 
     
     
         5 . The apparatus of  claim 1 , wherein the processor is to convey an alert message when the condition of the seal reaches a predetermined level. 
     
     
         6 . The apparatus of  claim 1 , wherein the processor is to:
 determine a rate of change of the torque; and   determine an estimated remaining number of seal wearing cycles until the condition of the seal reaches a predetermined level based on the torque and the rate of change.   
     
     
         7 . The apparatus of  claim 6 , wherein the processor is to determine a frequency of the seal wearing cycles and an estimated amount of time until the condition of the seal reaches the predetermined level based on the torque and the frequency of the seal wearing cycles. 
     
     
         8 . The apparatus of  claim 6 , wherein the processor is to determine a count of seal wearing cycles and an estimated remaining number of seal wearing cycles until the condition of the seal reaches the predetermined level based on the count. 
     
     
         9 . An apparatus, comprising:
 a housing; and   a processor positioned within the housing, the processor to:
 determine a seal wearing cycle of a flow control member of a rotary valve, the seal wearing cycle including movement of the flow control member between a first position in contact with a seal and a second position; 
 in response to determining the seal wearing cycle, increment a count of seal wearing cycles; 
 associate the count with a variable corresponding to an estimated number of seal wearing cycles over a useful life of the seal; and 
 estimate a condition of the seal based on the count and the variable. 
   
     
     
         10 . The apparatus  claim 9 , wherein the estimate of the condition of the seal comprises a calculation of a ratio based on the count and the estimated count of seal wearing cycles over the useful life of the seal corresponding to the variable. 
     
     
         11 . The apparatus of  claim 9 , wherein the processor is to estimate the condition of the seal by:
 determining a value of the variable for the seal wearing cycle;   associating the value of the variable with one of a plurality of variable value ranges, each of the variable value ranges corresponding to an estimated number of seal wearing cycles over a useful life of the seal; and   calculating a ratio based on the count and the estimated number of seal wearing cycles over the useful life of the seal.   
     
     
         12 . The apparatus of  claim 11 , wherein the processor is to determine each of the estimated number of seal wearing cycles over the useful life of the seal based on a test of another rotary valve similar or identical to the rotary valve. 
     
     
         13 . The apparatus of  claim 9 , wherein the processor is to determine an estimated number of seal wearing cycles remaining until the condition of the seal reaches a predetermined level. 
     
     
         14 . The apparatus of  claim 13 , wherein the processor is to determine a frequency of seal wearing cycles and estimate an amount of time remaining until the condition of the seal reaches the predetermined level based on the count and the frequency. 
     
     
         15 . The apparatus of  claim 9 , wherein the second position is a position where the flow control member initially engages or disengages the seal. 
     
     
         16 . A tangible machine readable storage medium having instructions stored thereon that, when executed, cause a machine to:
 determine a seal wearing cycle of a flow control member of a rotary valve, the seal wearing cycle including movement of the flow control member between a first position in contact with a seal and a second position;   determine a torque of an actuator operating the flow control member for the seal wearing cycle; and   estimate a condition of the seal based on the torque.   
     
     
         17 . The tangible machine readable storage medium as defined in  claim 16 , wherein the machine readable instructions, when executed, cause the machine to send an alert message when the condition of the seal reaches a predetermined level. 
     
     
         18 . The tangible machine readable storage medium as defined in  claim 16 , wherein the second position is a position of the flow control member where the flow control member initially engages or disengages the seal. 
     
     
         19 . The tangible machine readable storage medium as defined in  claim 16 , wherein the machine readable instructions, when executed, further cause the machine to determine a rate of change of the torque and an estimated remaining number of seal wearing cycles until the condition of the seal reaches a predetermined level based on the torque and the rate of change. 
     
     
         20 . The tangible machine readable storage medium as defined in  claim 19 , wherein the machine readable instructions, when executed, cause the machine to determine a frequency of the seal wearing cycles and an estimated amount of time until the condition of the seal reaches the predetermined level based on the torque and the frequency of the seal wearing cycles.