Artefact · M04 Gas supply, meters & regulators
Domestic meter regulator
A cutaway regulator showing how the diaphragm, loading spring and valve hold outlet pressure steady as demand changes, how it locks up, and how it fails.
What you're seeing
A domestic angle regulator floating in space, shown whole or cut through its centre. Gas arrives through a flexible hose on the left into the chamber above the valve seat, passes down through the seat past the valve disc and leaves by the outlet at the bottom. An impulse passage carries outlet pressure to the underside of the diaphragm, while the loading spring pushes down on top: the balance between the two sets how far the valve opens. In the cross section the blue gets darker where the pressure is higher; the spring chamber above the diaphragm is open to air through the breather. Raise the demand and the outlet droops slightly while the valve opens further; stop the flow and the outlet rises until the disc seats and the regulator locks up. You can wind the adjusting screw, remove the spring, and show two failures: a ruptured diaphragm (gas escapes from the breather and the outlet rises towards inlet pressure) and a valve disc that has come off its spindle (the regulator stops regulating). Travel is exaggerated, and the droop curve and turns per millibar are illustrative.
What it shows
- Whole, cross-section and exploded views of the regulator
- Outlet pressure drooping as demand rises, and locking up at no flow
- Adjusting the loading spring, and the effect of a ruptured diaphragm or detached valve disc