Problems with double flange differential pressure transmitter for measuring high temperature media (around 300 degrees)
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Please discuss it: Are there any measures similar to insulation and heat tracing for the capillary tube of our double-flange differential pressure transmitter that measures high-temperature media (around 300 degrees) in winter? Because some manufacturers explain that the usable ambient temperature of the high-temperature silicone oil used is above 0 degrees. I wonder if you have ever encountered the situation where the measurement of the double flange transmitter is inaccurate when the temperature is about minus 10 degrees.
The ambient temperature requirements of high-temperature silicone oil from various manufacturers are different, but if the work is below 0 degrees, insulation must be done, and heat tracing will depend on the site conditions! It can not only ensure the temperature but also prevent the temperature from being too high to prevent the silicone oil from vaporizing! :handshake
Generally, the isolation fluid of the double-flange capillary tube for measuring high-temperature media should be used above 0 degrees, so it should be kept warm and heated, but care should be taken not to vaporize the isolation fluid.
The double-flanged capillary tube does not require heat tracing because the silicone oil flushed inside has a freezing point of minus 40 to 50 degrees Celsius.； The double-flange capillary tubes in our factory have never experienced freezing and condensation due to low temperature. However, heat tracing must be installed at the pressure valve and pressure point to prevent freezing and condensation.
Double-flanged capillary tubes do not require heat tracing
The capillary tubes of some double-flange transmitters need to be insulated and heated. However, it should be noted that the capillary heat tracing heat on the positive and negative sides should be equal, otherwise it will cause inaccurate measurements.
I have used many double-flange transmitters, and the capillary tubes have never been insulated, and there have never been inaccurate measurements. I wonder if anyone has encountered it?
This is the first time I heard that the capillary tube needs to be heated. It seems that if the heating temperature is different, it will cause the silicone oil to expand differently.
We have not used a double flange for the measuring medium of 300 degrees, but the technical requirement for the working temperature of Rosemount's high-temperature silicone oil is zero degrees. I think it is best to only perform heat preservation instead of heat tracing.
Double flange liquid level gauge capillary tube does not need to be insulated
Because the medium is 300 degrees, everyone should pay attention to this condition. The operating temperature of silicone oil from various manufacturers is different! But generally speaking, high-temperature silicone oil must be used for this condition. The freezing point of high-temperature silicone oil must be above 0 degrees. If the ambient temperature is low, measures must be taken!
This post was last edited by 955559 on 2018-7-20 09:46. It contains advertisements and has been edited.
This is related to the measured medium and the length of the pressure tube. Whether heat tracing is required depends on the actual situation. The characteristics of silicone oil are relatively stable and have no effect at about minus 10 degrees. The measurement of the double flange transmitter should be accurate.