Probably very constructive ball valve beaten and studied, so as soon as a fundamentally new schemes will not be. The only thing any more questions on the strips. Now the most common is Teflon (PTFE). He has a number of drawbacks, namely the low operating temperature of 200 ° (actually a plot of the fall of the working pressure of the medium temperature pressure curve begins its fall down already from 120-130 °) and low relative pressure, which can withstand a valve (3/4″ Threaded Brass Ball Valve). Another polyurethane sealant capable of withstanding more than 6.3 MPa, but it does not work above 80 °. Therefore, in the near future more efforts will be aimed at finding a more versatile material, as well as reduce costs associated with a decrease of metal (the problem of many domestic taps) and increased productivity.
only in the West, I have never met. But in short position is – conditioned aisles of more than 250 mm. Why? Because the development of this size is associated with higher costs. But not everyone is ready for this. Some simply follow the path of least resistance. (All the above applies to the ball valve with a nominal pressure up to 4,0 MPa. On the other yet it’s difficult to judge.)
Sep 3rd, 2010
