Trunnion ball valve for high pressure, and hydrogen station

Patent metadata

Field	Value
Publication number	US-2016025231-A1
Application number	US-201314378722-A
Country	US
Kind code	A1
Filing date	Feb 28, 2013
Priority date	Feb 28, 2012
Publication date	Jan 28, 2016
Grant date	—

Abstract

A trunnion ball valve for high pressure and a hydrogen station are provided, which achieves low torque during operation, and whose durability is improved to maintain sealing ability for a long period of time. In a trunnion ball valve including a ball provided inside a body main unit in a freely rotatable manner; and a seal mechanism provided on positions on both sides of the ball so as to be in seal contact with the ball, the seal mechanism including: a seat retainer having a sealing surface that is to be in seal contact with a ball surface of the ball; a spring member provided for applying elastic force on the sealing surface side; and a sealing member provided on an outer surface of the seat retainer, at least both of the sealing surface and the ball surface has a coating layer of diamond-like carbon provided thereon, so as to exhibit sliding ability and sealing performance.

First claim

1 . A trunnion ball valve for high pressure, comprising:
a ball provided inside a body main unit in a freely rotatable manner; and a seal mechanism provided on positions on both sides of the ball so as to be in seal contact with the ball, the seal mechanism comprising:
a seat retainer of a tubular shape having a sealing surface that is to be in seal contact with a ball surface of the ball;
a spring member provided for applying elastic force on the sealing surface side; and
a sealing member provided on an outer surface of the seat retainer,
at least both of the sealing surface of the seat retainer and the ball surface with which the sealing surface is to be in contact having a coating layer of diamond-like carbon provided thereon, so as to exhibit sliding ability and sealing performance.

2 . The trunnion ball valve for high pressure as set forth in claim 1 , wherein the sealing surface of the seat retainer is set at a position deviated from a spherical diameter center of the ball surface so that the sealing surface has a slightly longer radius than a radius of the ball surface, and the sealing surface has a sealing position with the ball surface at a substantially center position of the sealing surface.

3 . The trunnion ball valve for high pressure as set forth in claim 1 , wherein the sealing surface of the seat retainer has one part of a drawn semispherical surface serve as a trajectory surface, the semispherical surface drawn to have a slightly longer radius than that of the ball surface, the slightly longer radius being a length from a point deviated from a spherical diameter center of the ball surface along a Y-axis direction by a predetermined distance, at an angle 180° in a direction opposite to a side to which the point is deviated, the Y-axis running orthogonally to an X-axis that runs in a flow channel direction of the ball.

4 . The trunnion ball valve for high pressure as set forth in claim 1 , wherein the seat retainer has a base material hardness set higher than a base material hardness of the ball.

5 . The trunnion ball valve for high pressure as set forth in claim 4 , wherein the base material of the seat retainer is BeCu alloy, and the base material of the ball is stainless steel.

6 . The trunnion ball valve for high pressure as set forth in claim 1 , wherein either one or both of the sealing surface and the ball surface has a conforming layer provided on a surface of the coating layer.

7 . The trunnion ball valve for high pressure as set forth in claim 1 , wherein the ball has an upper shaft section and a lower shaft section provided in an integrated manner, the ball being provided on an outer periphery of the upper and lower shaft section in a freely rotatable manner via a radial bearing, and the ball being provided in a freely rotatable manner via a rotational force of a stem that is joint to the shaft section, the stem having on a lower end thereof a parallel two-surface groove on which a parallel two-surface section provided on an upper end of the shaft section is provided to work in connection therewith, and when the ball is pressed by high-pressure fluid while the valve is closed, the ball having the upper and lower shaft sections is supported in a perpendicular state in the secondary direction.

8 . The trunnion ball valve for high pressure as set forth in claim 7 , wherein the radial bearing is a member in which an inner peripheral surface of a rigid cylindrical body is coated with polytetrafluoroethylene.

9 . The trunnion ball valve for high pressure as set forth in claim 7 , wherein the trunnion ball valve is a manually operated ball valve to which a handle for manual operation is provided on the upper end of the stem, or is an automatically operated ball valve in which the upper end of the stem is connected to an actuator installed in the body main unit for automated operation.

10 . A hydrogen station comprising a trunnion ball valve for high pressure as set forth in claim 1 , in a supply line for high pressure hydrogen.

Assignees

• Kitz Corp

Inventors

• Watanabe Osamu
• Watanabe Tetsuya

Classifications

• F16K25/005

  Particular materials for seats or closure elements · CPC title

• F16K31/60

  Handles {(form, features or function of taps or faucet handles for domestic plumbing installations E03C1/04)} · CPC title

• F16K5/227

  for plugs with spherical surfaces · CPC title

• F16K27/067

  with spherical plugs · CPC title

• F16K5/0636 Primary

  the spherical plug being insertable from the top of the housing · CPC title