From: Larson, Rod
Sent: Friday, September 19, 2008 8:06 AM
To: Smith, Jim
Subject: IBST
Jim,
Just to let you know....that funny restrictor valve on the IBST actuators in-between the s/v and actuator does NOT like 8000+ psi from running out of oil cuz the system doesn't have any accumulators. I blew the sucker clear across the lab. Then we dumped about 60 gallons on the floor cuz there are NO hand valves between the pump and the HSM. Of course the %^%(*(#(&$&!(#&($ HSM has an ORIFICE in the Return Check Valve AND the (*&$(#$&&*#@$@( HSM shunts pressure to return. Therefore, you have a direct siphon from the pump reservoir to the hole in the actuator. Did you know that even the darn drain line was dumping oil out the actuator.....geeeeez......
 
This system has about a dozen major problems and 25 minor ones....
 
1. no hand valves on the pump or near the input of the HSM - can't even replace input hose on the HSM w/o losing a LOT of oil.
2. return back pressure almost zero - 15 psi max - not the 50-75 required - even the 256's squawk
3. no accumulators to speak of - line hammer - and cannot run 1 cycle at max performance curve between 0.5 Hz and about 4 Hz.
4. cannot run Northridge or Kobe earthquakes - run out of oil...
5. pump is crummy 505 and not 506 - had to turn up the needle valve to get more flow thru heat exchanger cuz sucker overheats on normal day
6. 505 does not have proper filtration - only on main return line - no recirculating filter loop - have to blow out servovalves with 1-2 volts of dither every 1/2 day.
7. 469D cannot accept external analog commands OR extra tranducer inputs to add into Data Recorder acquisition (time syncing)
8. 469D cannot output any system signals in analog form for external data acquisition systems.
9. 469D cannot produce external trigger for external data acquisition
10. 459D cannot shut off pump cuz shared pump with 793 structural system and does not have any shutoff solenoid.
        (this ol' fat man made it across the lab in about 10 seconds to shut that bad boy off while gushing oil continued AFTER HSM off)
11. my head is tired...but there is more....
 
Rod