Pressure tube, also called as pulse tube, is a kind of tube directly connected with process media. It is the most complicated tube with the most requirements of installation.
Owing to its direct contact with process media, the selecting of tube is related with the physical, chemical quality and operation condition. All in all, the tube needs to work under pressure or normal pressure and has certain strength and sealing, so seamless steel tubes are used for these tubes. Plus and minus tube should be as close to the lay position as possible in case any signal distortion occurs caused by different temperature in these 2 tubes. In extreme cold conditions, pressure tube should be protected with anti-freezing measures, heated by heat tracing cable and steam while preventing overheating. The gasification of liquids in tube will lead to false pressure difference.