Which is better for large-diameter circulating water separation: plug-in electromagnetic or plug-in ultrasonic?
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For the DN1800 circulating water pipeline, with a flow rate of around 10,000 cubic meters per hour, a pressure of 4 kilograms, and temperatures between 20~30°C, flow meters need to be installed. Due to cost constraints, should an insert-type electromagnetic flow meter or an insert-type ultrasonic flow meter be chosen? Which one offers more stable performance and higher accuracy? If possible, please recommend some brand manufacturers
Just choose an insert-type electromagnetic flowmeter~~ it’s inexpensive, and no high precision is required~~
Insertion-type electromagnetic flowmeters are available, with an accuracy of 1.5%; we can discuss this further if needed
Plug-in types are very difficult to install; electromagnetic types are more convenient.
It is recommended to use an insert-type rotameter: weld a short threaded tube onto the pipe, and then screw the rotameter onto it. Recommended brand: American + GF + SIGNET P51530 rotameter. http://yunrun.com.cn/upload/201708/17/201708171731321771.png http://yunrun.com.cn/upload/201708/17/201708171731487189.png Changhui Instruments, yunrun.com.cn/
Don’t use the insert type. Use wet ultrasonic or bundled ultrasonic.
I think a pitot tube can be used to measure flow accurately. At the very least, it is accurate; when it comes to the flow rate at a single point, there is a solid theoretical basis, and it is not necessary to conduct actual measurements throughout the entire pipe. Using a point to represent the whole area, there is always some flow velocity that can reflect the average flow velocity across the cross-section – the optimal location for this point is around 1/3 of the radius. With some mathematical adjustments to determine the flow rate of large pipes, it’s really not difficult at all, and it doesn’t cost much either.
In comparison, large-diameter electromagnetic flowmeters have too poor accuracy. It’s better to use ultrasound, specifically an ultrasonic flow meter that employs the time difference method.
For large-diameter ones here, I use those with an embedded electromagnet
The plug-in electromagnetic type is better; its manufacturing process is more mature, it offers higher precision and lower installation requirements. The ultrasonic external clamping type requires calculations before installation, and frequent adjustment is needed when changing the dressing
I see that many people recommend plug-in electromagnets, but the ones I’m using currently give only mediocre results; they produce some readings, yet the values are highly inaccurate and unstable. I was wondering if anyone knows of any manufacturers that produce high-quality products – could you please recommend them?