Bystronic 4400 over pressure on shutdown

[jetray]

Hi All,
Has anyone encountered a Bystronic 4400 laser unit pushing the plugs out or over pressure warnings
while running ? - worst of problem is during shutdown cycle when flooding with nitrogen if error happens
at about 400 hpa on laser view screen - my digital test gauge plugged into test port jumps from minus 620 hpa
to plus 20 hpa - while laser view is still reading 400 and so it keeps flooding cavity and then an anode plug will
pop out because of the over pressure.

Our digital test gauge should read about 30 hpa when flooding is finished - the problem seems to be at some point
the gas mix chasis is reading /sending the pressure wrong or the EPG valve which measures / sets ambient pressure value
is not reading or setting ambient correctly.

When gas mix working correctly laserview hpa values and digital test gauge values all correspond with each other
all the way to shut down

Burket proportional valves are not leaking after shutdown is complete as digital pressure gauge does not rise above
30 hpa if laser gas bottles are left on.

There has been 2 revised model of gasmix chasis since 4400 first released - we have replaced once already and
are on the 1st revision type and will try the latest type unless anyone knows the problem maybe elsewhere
or if an EPG valve replacement/fix is possible - would be disapointed to spend 20k on a gasmix chasis if it didn't
fix the problem.

Thanks
JetRay

 

[krugtech]

there's 2 pressure sensors, one in the exhaust valve that reads absolute/operating pressure, above around 400 the controller switches to an atmospheric referenced pressure sensor so it can overpressure the system properly regardless of atmospheric pressure. you should be able to find this input in the analog section of the laserview diagnostics. it's probably flat lined. I understand it's made by Burket. Bystronic is usually not willing to sell this part separate. I've heard o f people trying to by direct from burket but it's a Bystronic flagged part number and not available. I've heard of engineers doing a little leg work and getting the same part from the same pace I mean c'mon I have to buy a whole damn manifold when a simple common pressure sensor took a crap? bet I could find one on Amazon.com

Until you fix it shut it down it step and only pressureize to 400. low flood better than blowing caps out. or just run 24/7! ha ha


Chris Krug

http://krugtech.com/

Maximum Up-time, Minimum BS