First aid: The owner needs to change the design
Thread Content
Colleagues, I have to trouble you all again. This time, the client wants to change the design. Here’s the situation: there are four flow meters, and we selected three vortex flow meters along with one average velocity tube. The operating condition is steam； Pressure: 0.3 M, Temperature: 240 degrees, Flow rate: MAX: 26,000 KG/H; NORMAL: 24,000 KG/H, Density: 13 KG/M3, Pipe diameter ； 300 (two vortex flow meters) ； Desulfurization liquid: Pressure: 0.25 M; Temperature: 10 degrees; Flow rate: 1200 M3/H; Density: 1115 KG/M3; Pipe diameter: 300 (1 vortex flow meter) ； Semi-water gas: Pressure: 0.8 M, Temperature: 40 degrees, Flow rate: MAX: 60,000 NM3/H, MIN: 50,000 NM3/H, Density: 3.8 kg/m3, Pipe diameter: 450 (1 uniform-flow tube). Now the owner wants to replace all of these with V-cones, but I’ve heard that V-cones are not widely used in many applications, as there have been accidents where the tip of the cone broke off and injured people. Since I’m not very familiar with V-cones, I’m not sure whether it’s possible to use them in these applications. I wonder if there are any friends who have used V-cones in seawater treatment; could they explain the effects of their use? I don’t want to change it, because the responsibility is great; if something goes wrong, I’ll have to bear the consequences myself. By the way, what type of flow meter is suitable for these operating conditions? Can a target type or constant velocity tube be used?
I have a few questions. 1. Regarding steam； Pressure 0.3 M, temperature: 240 degrees – is this superheated steam? Has the superheated steam been measured, with vortex flow meter plus temperature and pressure compensation used? 2. If the medium temperature is above 260 degrees, high-temperature sensors can be used. Will LZ use high-temperature vortex flow meters? 3. Regarding the diameter of the steam flow meter, based on the flow rate, I think DN200 will suffice ； For the desulfurization liquid, a DN250 model will do; why didn’t LZ choose an electromagnetic flowmeter with DN250? 4. Regarding water gas, is the medium clean? 5. Finally, in response to the original poster’s question about whether a V-shaped cone can be used, I personally think it is possible, but installing, maintaining, and repairing a V-shaped cone is quite troublesome and costly; so why go through the hassle?
V-cone flow meters don’t have very high requirements regarding straight pipe sections; they can be used in such conditions. Although our factory uses them not frequently, they are employed in steam pipelines, and after several years, it seems that no maintenance is necessary
Using a V-cone is fine; your choice is also correct.
If the client wants to make changes, just have them issue a change order; it has nothing to do with you
In fact, many times everyone has the same goal, but from a professional perspective, the client is not as knowledgeable as you are. When faced with such clients who insist on doing something, you have no choice but to agree, after all, they are the client, and as long as you can protect yourself from liability that’s enough. The social situation is like this; what can be done?:
I have never used a V-cone, but I personally think this measurement should be fine. It mainly focuses on safety issues; I think it’s due to human factors – things like not being able to perform online purging can be avoided. It is recommended to submit relevant suggestions to the property owner. Additionally, the selection of manufacturers must also be strict, with necessary inspections carried out; requirements such as flaw detection of the welded areas of the vertebrae and heat treatment should be specified.
Reply 2# sun_fm: How much is the electromagnetic flowmeter for DN250?
Provide proper guidance to the owner and explain the situation. If the owner still insists, then take the necessary follow-up actions.