Ball Model: BQ41F necking insulation valve characteristic of the series valve with insulation, cold properties. Designed and manufactured according to GB flange connection by 79-94 standards for manufacturing used in petroleum, chemical, metallurgy, pharmaceutical industry. As a result of the steam valve insulation jacket. Therefore, even if the outside temperature drops below freezing, the valve is still operational flexibility to ensure that the pipeline can be disconnected, the advantage of the general control valve does not have. It is ideal for heavy oil pipeline control valves. According to user needs jacketed steam injection, oil, cooling water, air conditioning and so on. Use warm or the temperature of the entire valve length to achieve the required cooling. To prevent crystallization medium.