Installation sequence of temperature, pressure, and flow meters on pipelines
Thread Content
When measuring temperature, pressure, and flow rate on a pipeline, is the installation order of the instruments such that pressure comes first, followed by flow rate, and then temperature, in the direction of the medium flow? Why
If pressure and temperature sensors are installed together, pressure should be measured first and then temperature. The flow meter can be placed in a location that meets the requirements for a straight section and facilitates maintenance; all of them are remote-sensing types
Generally, pressure is applied first and then temperature; the use of an insert-type element can cause changes in the fluid flow. Flow meters usually need to meet the requirements of the process, including those regarding the straight pipe sections before and after the meter. Adjustments are only made with the consent of both the instrumentation and process engineering teams, if it is necessary for ease of operation and maintenance
Pressure is applied first, followed by temperature; the temperature is introduced at an angle in the opposite direction to the flow of fluid. It is very important to choose the installation location carefully and to install the flow meter properly. Mistakes during installation can, in mild cases, affect the measurement accuracy, while in more severe cases they can impact the flow meter’s lifespan or even damage it. The requirements for straight pipe sections in the installation of vortex flowmeters are very important. Its detailed requirements are as follows: The flow meter has certain requirements regarding the straight pipe sections upstream and downstream of the installation point; otherwise, it will affect the measurement accuracy. If there is a converging section upstream of the flow meter installation point, there should be a straight section with a diameter equal to that of the pipe of at least 15D (where D is the pipe diameter) upstream of the flow meter, and a straight section of at least 5D in diameter downstream of it. If there is a flare pipe upstream of the flow meter installation point, there should be a straight section with a diameter equal to that of the pipe of at least 18D (where D is the pipe diameter) upstream of the flow meter, and a straight section of at least 5D in diameter downstream. If there is a 90° elbow or a downward connector upstream of the flow meter installation point, there should be a straight section with a diameter equal to that of the pipe of at least 20D upstream of the flow meter, and a straight section of at least 5D in diameter downstream. If there is a 90° elbow on the same plane upstream of the flow meter installation point, there should be a straight pipe section of equal diameter of at least 25D upstream of the flow meter, and a straight pipe section of equal diameter of at least 5D downstream of it. The flow control valve or pressure control valve should be installed as far downstream as possible, at a distance of 5D from the flow meter. If it must be installed upstream of the flow meter, there should be a straight pipe section of equal diameter of at least 25D upstream of the flow meter, and a straight pipe section of equal diameter of at least 5D downstream of it
Pressure gauge first, then thermometer； For flow meters, it is necessary to follow the recommendations of the flow meter manufacturer
The sequence between the temperature and pressure measurement points is determined according to the following rules: The flow meter must also meet the requirements regarding the straight pipe sections