Pressure transmitter application in harsh environments
From: Issued date 2021.01.29 Back
With its advanced technology, easy installation, high accuracy, and low maintenance, pressure transmitters have been widely used in harsh environments and have been affirmed. However, there are still some problems, the actual pressure and the measurement result are in error. Research and investigation found that the main reason is unreasonable application.
1. Negative pressure environment
In a negative pressure environment, the requirements for the transmitter are mainly reflected in the airtightness of the transmitter and the choice of oil filling. At the same time, it is necessary to prevent the wetted diaphragm from being in a negative pressure state for a long time. Diaphragms that are under negative pressure for a long time are prone to deformation, which seriously affects the service life and measurement accuracy. In order to ensure the overall airtightness of the pressure transmitter, a fully welded method must be adopted. In a negative pressure environment, the working range of various filling fluids will be greatly affected, and it is easy to decompose and vaporize, and lose the pressure guiding function, which affects the measurement. In addition to the above-mentioned influence caused by the pressure transmitter itself, the pressure transmitter can also be used in a negative pressure environment through a reasonable installation position.
2. Corrosion and wear environment
In a corrosive and abrasion environment, there are mainly two ways to protect the diaphragm, that is, adding a protective cover to the diaphragm and selecting a special material metal with high hardness and corrosion resistance. Different methods can be adopted according to the actual working conditions. In the environment where the measurement environment is corroded and worn, the method of adding a protective cover to the diaphragm is an effective solution to solve the pressure measurement. But applying this cover in the measurement will have a certain impact on the measurement performance. In a strong corrosive environment, the isolation diaphragm of special material solves the problem of damage to the diaphragm by the measuring medium, but users usually ignore the problem of corrosion at the welding point with the diaphragm. In order to solve this kind of problem, special material metal should be used as a whole.
3. High temperature environment
The use of pressure transmitters in high-temperature environments is mainly focused on the selection of oil filling and heat preservation. In addition, due to improper cooling measures at the installation nozzle, the process temperature is too high, exceeding the very high value that the diaphragm can withstand, which is one of the main causes of damage to the diaphragm. The solution is to use an oil-filled oil with a larger temperature resistance range and take cooling measures at the same time.
Founded in 2005, Nanjing Wotian Technology Co., Ltd. is a national high-tech enterprise, a private technology enterprise in Jiangsu Province, a specialized and special new small and medium-sized enterprise in Nanjing, and an outstanding private enterprise in Jiangning District; the company has been assessed as the Nanjing Engineering Technology Research Center, Nanjing Engineering Research Center, Nanjing Enterprise Technology Center, Nanjing Post-Doctoral Innovation Demonstration Base; It is the unit that participated in the formulation of the national standards for "Silicon Piezoresistive Pressure Sensitive Chips" and "Silicon Pressure Sensors".