Leakage blocking device of a valve

11754,198

17/912722

September 07, 2020

A leakage blocking device of a valve is disclosed. When a fluid flowing in a flow path 11 leaks through a gap between the outer circumferential surface of a valve stem bottom (21) and a bottom guide hole (31), a plug 53 of a piston 50 is pushed into a sealing oil chamber 45 by a pressure P1 of the leaked fluid acting on a bottom pressure acting surface S1 of the piston and pressurizes a sealing oil L in the sealing oil chamber 45 to a pressure P2 higher than the pressure P1 of the leaked fluid, thereby blocking leakage of fluid of the valve.

Ko, Ki Chang (Gimpo-si, KR)

1. A leakage blocking device of a valve for blocking leakage of fluid through an outer circumferential surface of a valve stem comprises: a bonnet (30) having a lower guide hole (31) in which the valve stem (20) slidably fits to guide a lower portion (21) of the valve stem (20), and a bore (32) coaxially extended from an upper end of the lower guide hole (31) and having a diameter larger than the lower guide hole (31); an upper cover (40) covering an upper end of the bore (32) and comprising an upper guide hole (42) in which an upper portion (22) of the valve stem (20) slidably fits, and a sealing oil chamber (45) filled with pressurized sealing oil (L) and having a diameter smaller than that of the bore (32) of the bonnet (30) and larger than that of the upper guide hole (42); and a piston (50) comprising a larger diameter portion (52) slidably fitting in the bore (32) of the bonnet (30) at a lower end, and a plug (53) slidably fitting in the sealing oil chamber (45) at the upper end thereof, wherein the larger diameter portion (52) has a through-hole (51) for the valve stem (20) to slidably fit therein and a bottom pressure acting surface (S 1) of a smaller cross-sectional area at a lower end to receive pressure of leaked fluid through a gap between the through-hole (51) and the valve stem (20), and the plug (53) having a top pressure acting surface (S 2) of a cross-sectional area smaller than the larger diameter portion (52).

2. The leakage blocking device of a valve of claim 1 , wherein the sealing oil chamber (45) having at least an inlet (46), and the inlet (46) being sealed with a cap (47).

3. The leakage blocking device of a valve of claim 1 , wherein the plug (53) of the piston (50) is pushed into the sealing oil chamber (45) by a pressure (P 1) of leaked fluid acting on the bottom pressure acting surface (S 1) thereof to pressurize the sealing oil (L) in the sealing oil chamber (45) to a pressure (P 2) higher than the pressure (P 1) of the leaked fluid.

4. The leakage blocking device of a valve of claim 1 , wherein the upper cover (40) comprising a sleeve (43) extended downwardly from the bottom thereof and slidably fitted in the upper end of the bore (32) to form a lower portion of the sealing oil chamber (45).

5. The leakage blocking device of a valve of claim 1 , wherein an O-ring is installed on an inner wall of the through-hole (51) of the piston (50), an outer circumferential surface of the larger diameter portion (52) of the piston (50), and an inner wall of the upper guide hole (42) of the upper cover (40).

5979483 November 1999 Zapalac
6161835 December 2000 Arbuckle
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2006-234171 September 2006
10-2007-0078761 August 2007
10-2014-0083576 July 2014

International Search Report for PCT/KR2020/012009 dated Nov. 17, 2020 (PCT/ISA/210). cited by applicant

edspgr.11754198