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Low temperature valve material cold brittle phenomenon

Because the valve used in the pipeline is processed and manufactured according to the characteristics of the pipeline itself and the medium inside the pipeline, so it can also be said that the current valve structure is basically formed because of the many needs of the pipeline and medium. When it comes to the low temperature valve, this is a kind of need in the low temperature environment of the pipeline used in the valve, as the current transmission gas, oil, natural gas and other media pipeline, the use of this low temperature valve is indispensable.

The general low temperature valve refers to below -29 degrees ~ -196 degrees range, in -196 degrees ~ -269 degrees for the ultra-low temperature range. Petrochemical industry regulations below -20 degrees is considered as low temperature. General carbon steel, low alloy steel, ferritic steel, at low temperature toughness decreased sharply, brittleness increased. This phenomenon is called the cold brittle phenomenon of materials. In order to ensure the performance of the material, the low temperature valve material is not only required to have enough strength, toughness, processing performance at room temperature, but also requires the material to have the ability to resist embrittlement at low temperature. In addition, the low temperature valve material will shrink at low temperature, and the shrinkage rate of each part is different, which is the reason why some sealing parts leak. Therefore, it is necessary to study the material and structure of each part, to prevent the gap at low temperature, and the need for further analysis and testing of the material, before it can be used in the casting of the valve.

If you want to know more about all kinds of low temperature valves, electro-hydraulic valves and other information, please log on Wuxi Guantong Valve factory official website to contact us: m.hykssb.com