On 11/03/2019 20:25, Commander Kinsey wrote:
On Mon, 11 Mar 2019 19:14:47 -0000, Tim Watts wrote:

On 11/03/2019 18:49, Commander Kinsey wrote:

So the meter outside my house reduces the pressure?* I thought the
pressure was lowered for the whole street, like a substation reduces the
electricity to 240V.

I had noticed on older houses there's some kind of valve seperate from
the meter (often exposed to the outdoor weather!), presumably nowadays
it's inside the meter.

Your meter has a regulator that drops from an already lowish pressure to
20mbar.

http://www.gasinfo.uk.com/distribution_page.htm

Wow, 20mbar is damn low, I'm surprised that has the desire to move along
the pipe.

How do things like camping stoves work?* I assume the pressure inside a
butane cannister is much higher than that, and I don't think they have
pressure reducers.

I presume that the needle valve and feed to it is sized to be very
restrictive for the simple screw on burners.

The bigger ones fed by hose from a Calor cyclinder or the like have
28mBar regulators for butane or 37 mBar ones for propane. The different
pressures allowing for the different calorific values of the two gases
when using the same size jets, so allowing interchanging bottles
depending upon the ambient temperatures. Butane won't gas off from the
liquid on a cold day.

With high flows, such as a water heater (my parents' one needed a
regulator capable of 4kg of per hour), the boiling off of the gas can
cool the bottle too much and reduce gassing, so even in the summer, they
had to use two butane bottles in parallel or a single propane one.

SteveW