Shielded globe valve seal mechanism
A GLOBE VALVE is which uniquely shields and effects sealing compression of a soft seal such the valve can be used to control and fully stop flow of fluids of a variety of extremes of pressure, temperature, corrosive capacity and erosive capacity or combinations thereof that are known to destroy soft seals in current soft seal Globe Valves. The soft seal is completely shielded within an upper and a lower hard seal assembly attached to the end of valve stem. Axial movement of valve stem into valve control port to close valve causes contact of conical hard seal surface of upper sheath hard seal with matching upper conical sealing surface of valve body to greatly reduce fluid flow prior to protective lower hard seal and soft seal rings respectively sliding out of protective inner diameter of upper hard seal sheath into equal diameter of valve cylindrical port. Further downward axial movement of valve stem forces bottom of lower hard seal to compress against essentially annular counter bore surface near bottom of cylindrical port against force of very stiff internal spring to reduce cavity between lower hard seal and attachment disc rings which contain soft seal causing elastic radial expansion of soft seal into remaining annular flow path and against cylindrical sealing surface of the valve port to effect final bubble tight seal at final point of valve close. O-ring around fastener prevents fluid entrance to soft seal inside diameter region in order to prevent pressurization of inside of soft seal to allow pressure on outside of soft seal to force it back into cavity when cavity is redeveloped upon opening. Opening of valve occurs in reverse order of closing with soft seal similarly shielded at all points of opening and when valve is used in partially raised position as used to restrict flow.Cast Gate, Globe, Check Valves The mechanism also provides a bubble tight seal to not only pressure in the passage above the disc but under the disc which is not achievable by other types of soft seal globe valves due to loss of sealing contact force due to stem deflection up under pressure. The unique manner in which the seal is radially elastically expulsed against the cylindrical bore of the valve in the final closing and initial opening motion of the stem prevents sliding wear and minimizes plastic set of the seal such that the valve is uniquely capable of a much higher number of open and close cycles without wearing to point of leakage than are current soft seal globe valve designs.
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