Related to temperature and pressure reducers
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Hello everyone, I have another question for you (why do I say ‘again’?). This time it’s related to the pressure regulator that changes from 9.8 Mpa to 4.0 Mpa. We were using valves made by Huahui in China, along with actuators of the VP7s type produced by Chuanyi (with a maximum acting force of 73 KN at an air supply pressure of 6 kilograms). The problem now is that the valve won’t open when tried to be opened, or if it does open, the adjustment is unstable – the valve position keeps changing. Let me explain in detail. The valve is of the enclosed type pressure relief valve, and the diameter of its valve head (the enclosure) is 160 mm. I want to calculate the force required to go from a closed state to an open state. Is it scientific to use the method of multiplying the area by 9.8 MPa? The force calculated is approximately 197 KN. . . Or is there any experienced colleague who could share some insights? I’m now also considering whether the actuation force of the control valve is insufficient, and whether it’s necessary to switch to an electric actuator. It took me a long time before I decided to bother everyone with this question; I’m really sorry for that. .
It is recommended to use an electric version; pneumatic systems have very low torque, haha.
Thank you. I’m also in contact with them. How is the ABB actuator?
First, indicate whether your valve is air-open or air-close! Another suggestion is to reduce the opening degree of the manual valve upstream of the control valve and check whether the regulation remains stable! It is suspected that the large pressure difference before and after causes unstable regulation! Also, is an accelerator installed on your control valve! If no installation is recommended! If there are any suggestions for adjusting the air pressure of the speed booster! It can also stabilize the valve!
From the perspective of performance, ABB’s actuators are quite good, haha. .
The air supply might not be sufficient; 197 KN is an overestimate
For temperature and pressure reducers, it is recommended to use products from Wuxi Yadi; among domestic products, their temperature and pressure reducers are quite good.
It’s a double-acting valve; more precisely, it’s of the flow-blocking type (fluid enters from above and exits from below). The valve head doesn’t have any holes for balancing air pressure. Later, a sleeve was added below the valve stem, as it would close on its own at around 30% capacity – and then could not be opened again. At present, the adjustment of more than 50% of the flow rate is still stable; the concern is that when the usage amount is low and the valve opening becomes smaller, it might shut off on its own.
Thank you for your hard work. 190+kN should not reach this value. According to the manufacturer’s information, when the valve is opened, the negative valve disc opens first; therefore, 190+kN is definitely not achievable. It also certainly isn’t the 40kN value provided by the manufacturer, and the specific formula for this cannot be found. Now I am considering two scenarios. The first is that the actuator is indeed small; from what I understand about the Chuanyi VP8S, with a gas supply of 5 kg, it generates a force of 109 kN. Another issue is a problem with the valve core, which prevents the negative valve disc mentioned by the manufacturer from opening properly. If neither of these issues can be resolved... then considering replacing the valve body will be necessary.
Sweat, it’s better to consider electric actuators. You’re actually active on forums too? It’s better to focus on taking care of your health