Question regarding the fire protection aspects of floating ball valves
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I would like to ask the experienced colleagues for their advice: There has always been a question regarding the fire protection capabilities of floating ball valves. All available information discusses how, after the soft-sealing seat is damaged, the ball seals against the fire-resistant lip. However, in reality, once the soft-sealing seat is damaged, there is a gap between the ball and the fire-resistant lip, which prevents the creation of the necessary initial sealing pressure. Fixed ball valves are easy to understand, as the valve seat is floating, but in floating ball valves, the valve seat remains stationary. I would like to ask the seniors how they resolved this issue. Thank you
Floating fireball valve: The gaps between the ball and the fire-resistant lip are caused by inadequate manufacturing processes and precision. Fireball valves allow for some leakage; they are not completely airtight
Theoretically, the ball floats, so the principle is the same.
According to the manufacturing standards, the height of the fire-resistant groove should be at the same level as the valve seat; the metal valve seat with a gap that you see does not meet the standards, and there are no products in which a fire-resistant groove has been fabricated.
Is it possible to make the fire-resistant groove flush with the valve seat? This process isn’t that easy to solve.
This process can be easily carried out using a CNC machining center.
Could your company produce fireproof lips that are level with the valve seat? It feels hard to control
Precise control is required for the height gap between the fire-resistant ring of the valve body (valve cover) and the soft seal. Under the pressure of the medium, the floating ball enables sealing between the metal fire-resistant ring and the ball in the event that the soft seal is damaged; of course, this emergency sealing method allows for a certain level of leakage. Another thing to note is that such fire conditions must have sufficient temperature and duration to completely burn out the soft-sealed valve seat.
May I ask how much gap your products usually leave between the sphere and the fire-resistant lip?