Questions regarding high-temperature and high-pressure hydrophobic ball valves
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Dear sea friends, I have a question: why can’t ball valves be used in place of gate valves in certain critical parts of boilers and power plants?
Globe valves provide a tight seal and are easy to maintain online. Ball valves cannot ensure sealing when the sealing surface is damaged.
That’s correct. Gate valves provide forced sealing, while ball valves achieve self-sealing through the medium itself; consequently, ball valves have better sealing performance. As for the issue of damaged sealing surfaces, to the best of my knowledge, foreign manufacturers typically use STL for cladding, whereas ball valves are treated with cold spraying, giving them a hardness that is significantly higher than that of STL and thus a longer service life.
Ball valves are shut-off valves, while globe valves can regulate flow
For now, we are only discussing cut-off valves; adjustments will be discussed later::P
Ball valves are inexpensive; in applications with high parameters, give them a try – how many of them can prevent leakage?
Due to the limitations of the sealing material in ball valves, they are not suitable for high temperature and high pressure conditions.
Teacher Lu, price is indeed an issue, but for high parameters, I personally think ball valves present basically no difficulties. In terms of resistance to erosion at the open position, the principle of sealing, and the hardening treatment of the sealing surface, ball valves have certain advantages over gate valves. :P
The material used for hardening the sealing surface is such that domestic technology is relatively mature: P
At room temperature and under a pressure of 76 MPa, the valve has been operated more than 1,000 times with no leaks at all. As for high-temperature testing, it can only be verified after actual use in the field; it would be too wasteful to conduct such tests at one’s own expense.
It’s not that it’s irreplaceable; it’s just a matter of price. The stop valve actually doesn’t perform very well, with a service life of just over 3 months.