A kind of cryogenic gate valve with compound cooling disc bonnet

Abstract

Disclosed is a cryogenic gate valve with a composite heat dissipation disc valve cover. The cryogenic gate valve comprises a valve body. A valve clack is arranged in an inclined groove in the middle of the valve body. A valve rod is connected to the upper end of the valve clack. The upper section of the valve rod penetrates through sealing packing in a stuffing box on the upper portion of the valve cover, is then matched with a T-type nut on a support and is further connected with an actuator assembly. The valve clack is driven by an actuator to do vertical motion. A composite heat dissipation disc structure composed of a single large-diameter heat dissipation disc and a neck multi-ring small-diameter heat dissipation disc is arranged outside the valve cover, and therefore the average temperature conductivity is improved, the convection heat dissipation area and temperature difference of the cold neck periphery and the surrounding environment are increased, an excellent heat dissipation effect is achieved, it is ensured that the sliding fit portion of the valve rod and the packing is not frozen or bonded under the temperature above 0DEG C and opening and closing motion of the valve is reliable, hard frozen objects are prevented from scratching the valve rod and the packing, and the overall strength of the valve cover and the valve is improved. Cost is reduced, economic benefits are improved, a system is safe and reliable, and defects in the prior art are effectively overcome.

Description

Technical field [0001] The invention relates to a deep-cooling gate valve, in particular to a deep-cooling gate valve with a composite diffuser disc valve cover. Background technique [0002] Cryogenic gate valves play a very important role in the automatic control of the technological process of modern liquefied natural gas, liquid oxygen, liquid hydrogen, liquid helium, etc. in the cryogenic conditions of -150℃ to -250℃. In this process control, the flow parameters of the medium should be opened and closed according to real-time data signals. The sensitivity and reliability of the control action, the sealing performance between the valve stem and the packing, and the life are crucial. Because the lower part of the valve stem in the bonnet of the cryogenic gate valve is connected with the valve disc, the upper part is flexibly extended with the sealing packing in the sealing box, matched with the nut on the bracket, and then connected with the actuator, the space in the bonnet ...

AI Technical Summary

Problems solved by technology

However, in the existing technology, the bonnet of the cryogenic gate valve adopts a single-piece large-diameter cooling plate and an extended bonnet top, but the radius of the single-piece cooling plate increases, and the closer to the periphery, the cold temperature transmitted by the base surface of the cryogenic medium The smaller the convection temperature difference with the environment, that is to say, the lower the average temperature conductivity, the insufficient heat dissipation conditions, and the poor effect; it is necessary to lengthen the top of the bonnet, but the cold temperature of the peripheral wall of the extended top and the ambient temperature convection The area of ​​the valve is small, the heat dissipation conditions are not good enough, and the valve stem is too long, which will cause the instability of the vertically stressed pressure rod, seal leakage, and reduce the strength of the valve cover, while increasing the cost

Insufficient heat dissipation conditions will cause the sliding joint between the valve stem and the packing to freeze and bond, the opening and closing action torque is large or cannot be moved, and the frozen hard objects scratch the valve stem and packing, the service life of the cryogenic gate valve is short, and the replacement is frequent

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