Precautions for installing differential pressure type pressure transmitters in corrosive media – Huaheng Transmitter Manufacturer

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When the medium is corrosive, such as the gas, steam, or other condensed waters being measured, and it has a chemical effect on the elastic elements, an isolation device must be installed in front of the differential pressure type pressure transmitter. It is generally called an isolation tank. There are two methods of isolation: one involves the use of a sealing fluid, whereby a liquid that does not cause any damage to the elastic elements of differential pressure type pressure transmitters is used as the working fluid in the isolation tank; such liquids include glycerin, benzene, gasoline, mercury, vaseline, and heavy hydrocarbons, among others, and they serve as inert fluids. The choice of liquid should be determined by the properties of the gas protected by the instrument. Note that the liquid should not react with gases, vapors, and other condensed waters, nor should it dissolve them in large quantities. Under certain special conditions, solids are precipitated from steam and liquid during cooling. And it may block the pipeline leading to the differential pressure type pressure transmitter. In this case, an isolation tank must be installed near the pressure measurement point, and the pressure tapping pipes of the isolation tank as well as the tank itself must be heated to above the crystallization temperature using a steam jacket. The differential pressure type pressure transmitter is installed a bit further away from the isolation tank. Their connecting pipes are filled with a sealing liquid. Depending on the specific gravity of the working fluid and medium in the isolation tank. And two different installation methods are selected. The first method involves using a differential pressure type pressure transmitter, with its connection part inserted into a device filled with the sealed medium, when the specific gravity of the working liquid is greater than that of the medium. Another type is an isolation device that uses a protective film to fill the tube of the differential pressure type pressure transmitter with non-corrosive liquids such as glycerin. Common protective films include metal films such as Monel alloy, stainless steel, and copper, as well as rubber and plastic protective films. When the medium is at high temperatures, installing differential pressure transmitters requires taking into account the effect of the high-temperature medium on the elasticity of the elastic elements. It is generally required that the operating temperature be below 60°. To prevent high-temperature steam from being directly injected into the differential pressure type pressure transmitter. A siphon tube must be added during installation. Furthermore, it is also necessary to avoid attachments located near high-temperature heat sources in order to reduce the impact of such high-temperature heat sources, including radiation. To this end, the differential pressure type pressure transmitter must be installed at a sufficient distance from heat sources, or equipped with protective shields to absorb radiant heat. What precautions should be taken when storing differential pressure type pressure transmitters? 1. Environmental considerations: The less dust there is, the better protection the instrument will receive. Therefore, differential pressure transmitters should be used in a dust-free and non-corrosive environment, or at least in a place with as little dust as possible. Of course, the air temperature should not be too high either; maintaining a relatively low humidity is an excellent choice. The packaging boxes for the differential pressure transmitters produced by Sanchang Instruments are made of aluminum alloy, which serves to protect the instruments. 2. Instruments that are not in use should have their power turned off; this applies equally to differential pressure transmitters. When not used for an extended period, they should be charged once every three months. 3. Although the instrument has sufficient overload capacity, do not subject it to severe overloading, as this may damage the sensor and render the instrument unusable. 4. Precautions for internal instruments: Differential pressure type pressure transducer sensors are high-precision devices; the surface of the silicon diaphragm must not come into contact with solids, as this could damage the sensor. 5. Heat protection: Do not allow soldering irons or other heat-generating devices to come close to the display screen, to prevent damage to the plastic material. 6. Do not use chemical solvents indiscriminately: Do not use chemicals such as gasoline or alcohol to clean the panels. 7. Do not carry out repairs carelessly: Without professional testing skills and specialized testing equipment, do not open the cover to perform repairs, nor is it allowed to adjust internal components or replace materials; otherwise, the reliability of the instrument cannot be guaranteed. The data was collected and provided by Huaheng Instruments.