On Sat, 06 Dec 2008 23:40:14 +0000, Ron Lowe wrote:

All the hydraulic and compressed air pipework I deal with at work seals
at both ends of the coupling when disconnected. Why the heck is it not
fail-safe in this error condition?

Hydraulic obviously they don't want oil escaping from either side of the
coupling when it's disconnected.

The compressed air fittings I've seen are like gas cooker points in
that they isolate the /supply/ when disconnected, but there's no point in
isolating the load end: just more gubbins to make and install for
absolutely no purpose (unless one is trying to design fittings to allow
any half-arsed cowboy to fit them any way they like). You might equally
ask why domestic 13A plug & socket connectors aren't made so that they
shield the connectors at both ends, so if some dickhead decides to wire the
supply up to a 13A *plug* it doesn't kill anyone.

--
John Stumbles

Teenagers: tired of being harassed by your stupid parents?
Act now! Move out, get a job and pay your own bills,
while you still know everything!