Vacuum type low-temperature control needle valve

Abstract

The invention discloses a vacuum type low-temperature control needle valve, and belongs to the technical field of fluid transmission control in a low-temperature system. The vacuum type low-temperature control needle valve comprises an operating rod, a control connecting pipe, a fixing seat, a sleeve, a room-temperature mounting seat, a heat insulation outer pipe, a first sealing ring, a second sealing ring, a third sealing ring, a flow control needle, a valve body, a vacuum liquid suction capillary tube, a liquid output pipe and a vacuum interlayer. According to the vacuum type low-temperature control needle valve, the heat insulation vacuum interlayer is arranged outside the vacuum liquid suction capillary tube in a sleeving mode, so that heat leakage loss in the liquid conveying process is reduced to a great extent, the heat insulation outer tube is arranged on the control connecting tube in a sleeving mode, and three sealing rings are connected between the control connecting tube and the fixing base in a sealed mode, so that the heat leakage loss is reduced to a great extent. The heat insulation effect is further improved, the sealing performance is improved, and the phenomenon that due to untight sealing, a little air enters the vacuum type low-temperature control needle valve, and consequently the operating rod and the control connecting pipe are frozen is avoided.

Description

technical field [0001] The invention relates to the technical field of fluid transmission control in a cryogenic system, in particular to a vacuum type cryogenic control needle valve. Background technique [0002] In cryogenic refrigeration systems there is often a need to transport liquids into containers, such as transport and control 4 He (helium 4) or 3 In the case of He (helium 3) fluid, etc., a valve device with flow control is required at this time, and the most commonly used is the flow control needle valve. The existing flow control needle valve is mostly composed of a control operating rod, a needle valve seat and a flow control needle. Although its structure is relatively simple, it often encounters many problems in use. For example, the control operating rod does not have a good Insulation measures, which result in a larger loss of heat leakage during the liquid transmission process; in addition, because the sealing between the control lever and the fixed seat ...

AI Technical Summary

Problems solved by technology

Most of the existing flow control needle valves are composed of a control operating rod, a needle valve seat and a flow control needle. Although the structure is relatively simple, many problems are often encountered in use. For example, the control operating rod does not have a good Heat insulation measures, which result in greater heat loss during liquid transmission; in addition, because the control lever and the fixed seat are often not tightly sealed, resulting in a small amount of air entering and causing ice to freeze the control joystick problem

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