Pressure control for earthquake sensitivity shut-off valve

Patent · Tue Dec 26 04:00:00 EST 1989

OSTI ID:7180162

Lloyd, H E; Lloyd, M E

This patent describes a normally open shut-off valve closed by increased upstream pressure in a main thereto so as to protect a downstream service line therefrom. It comprises: a pressure sensitive means therein upstream pressure in the main is sensed ahead of a flow restriction in the main and downstream pressure is sensed following the flow restriction and operable to close the shut-off valve in response to upstream pressure greater than downstream pressure and comprised of a cylinder and piston means with a by-pass between the front and back of the piston and open to downstream pressure when the piston is retracted in the normal open condition of the shut-off valve. The by-pass being in open communication with upstream pressure, and the piston having a reduced diameter plunger for differential operation through a loose fitting opening exposed to pressure downstream of the shut-off valve and closed against a seat when subjected to high upstream pressure.

• Assignee: Safe-T-Quake Corp., El Monte, CA
• Patent Number(s): US 4889150; A
• Application Number: PPN: US 7-100549A
• OSTI ID: 7180162
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
022000* -- Petroleum-- Transport
Handling
& Storage
03 NATURAL GAS
032000 -- Natural Gas-- Transport
Handling
& Storage
CONTROL
CONTROL EQUIPMENT
ENERGY SOURCES
EQUIPMENT
FLOW REGULATORS
FLUIDS
FOSSIL FUELS
FUEL GAS
FUELS
GAS FUELS
GASES
NATURAL GAS
PETROLEUM
PIPELINES
PRESSURE CONTROL
SEISMIC EFFECTS
TRANSPORT
VALVES