||Stationary post, supporting ball|
||Rolling latch (no sliding friction)|
- The simple design consists of a swing-check valve and an acceleration-sensitive triggering mechanism.
- The ball is located on a stationary post (item #1) with a seat formed of certain angularity to horizontal. During a violent earthquake, the ball moves & strikes the reacting cylinder (item 2), which causes the CALIFORNIA Valve to close.
- Note the rolling latch! The latch mechanism automatically resets when subjected to very low amplitude accelerations. The mechanism will not creep in time to an actuating mode.
CALIFORNIA (formerly known as Koso) Valves are earthquake
sensitive gas shut-off valves. They are intended to close
in the event of a strong earthquake shaking to help prevent
gas flow into a structure where earthquake damage may have
occurred. These valves reduce the potential for fire or explosion
due to the release of natural gas or other fuel gas into structures
where gas lines, gas fixtures, or gas appliances may be damaged.
CALIFORNIA Valves utilize a swing-check valve
arrangement with an acceleration-sensitive triggering mechanism.
The trip mechanism consists of a steel ball that rests on
a tapered cup-shaped support. The horizontal motions of an
earthquake cause the ball to move from the center of the support,
which allows the ball’s mass to act upon the movable
pipe of the trip mechanism to actuate the valve and initiate
CALIFORNIA Valves do not use any source of
internal or external electrical power. They are designed to
remain closed until manually reset. These valves are intended
to be mounted in the gas line upstream or downstream of the
gas-line pressure regulator and gas meter outside the structure.
CALIFORNIA Valves are not intended to replace manual shut-off
valves installed in the gas service line.
Springs assist the valve’s disc to close,
and gas pressure assists in holding the disc in the closed
position. The trip mechanism is factory set and sealed. A
sight glass combined with an open/closed indicator that has
green (i.e., open) and red (i.e, closed) bars enables the
valve’s position to be easily and quickly determined.