Running round stock through oven

[Byucougar]

I run round stock in various diameters going through the oven horizontally rolling down being pushed by a chain conveyor with peridic ss rods that stick up into the furnace and when then rolling stock runs over it, it depreeses the rod and activates the switch. That is way it is suppose to work but due to high temerature - 1500 F, sometimes it doesn't work - anyone have any experience with anything else?

 

[PSE]

Could you do something non contact?

 

[Byucougar]

Yes, I could do non contact but will it handle th temperature?

 

[PSE]

Possibly. It would depend upon useful sensing distance. Hall effect sensors have a rather short range whereas some optical/machine vision systems would have longer range but may loose precision due to atmospheric distortion within the oven. Another possiblitity (though expensive) is to actively cool the sensor/detector to keep it within an acceptable thermal range. We did this when I worked on semiconductor processing equipment but then again we had ready access to a chiller and coolant as a standard part of the system.

Regards,