The Mudcat Café TM
Thread #164944   Message #3952978
Posted By: Iains
26-Sep-18 - 01:29 PM
Thread Name: BS: Massachusetts natural gas co.: explosions
Subject: RE: BS: MA natural gas co.: explosions
From the clip I assume it was a series of domestic mains that were overpressured. I find it surprising no safety valves were triggered by an overpressure of 20 times normal or that in line pressure transducers did not trigger shutoff valves. My first thoughts are a system design fault. A 20fold increase above normal should initiate a shutdown long, long before that level of risk is reached.
I will stick with off grid cylinders.
"As gas flows through the system, regulators control the flow from higher to lower pressures. If a regulator senses that the pressure has dropped below a set point it will open accordingly to allow more gas to flow. Conversely, when pressure rises above a set point, the regulator will close to adjust. As an added safety measure, relief valves are installed on pipelines to vent gas to the atmosphere where necessary.."

From the American gas Assosiation