- Low-temperature butterfly valves can operate in ranges below -29 degree (-20 degree F) and can handle temperatures as low as -196 degree (-321 degree F) in cryogenic applications.
1. cryogenic valve shell structure shape. Material selection is correct or not on whether the valve can work properly and reliably has an extremely important significance, the structural characteristics of butterfly valves and globe valves, gate valves, compared to not only avoid the shape of the irregularity, the shell wall thickness is not uniform, in the low-temperature cold shrinkage, temperature stress caused by the deformation, but also due to the butterfly valve is small in size, the shape of the valve body left and right is basically symmetrical, and thus the heat capacity is small; pre-cooling consumption is also small; the shape of rules And facilitate the valve cooling measures.
2. the choice of stem bushing: some low-temperature butterfly valve in operation, the valve's rotating parts of the sticky, bite phenomenon occurs from time to time, the main reason is that: pair of material selection is unreasonable, leaving a cold gap is too small, as well as processing precision is not high reasons. In the development of low-temperature valves, a series of measures to prevent the above phenomenon. On the valve stem, the lower liner selected with a small coefficient of friction and self-lubricating performance of SF-1 type composite bearings, which can be applied to some of the special needs of low-temperature valves. Metal-sealed butterfly valve has the characteristics that some ordinary valves do not have, especially small flow resistance, reliable sealing, rapid opening and closing, long service life and so on. Three eccentric metal-sealed butterfly valve is by the deformation of the elastic ring to achieve sealing, and thus do not need to rely on the medium force, so it can be used for two-way sealing.
