Thanks for all the great input - very interesting stuff (as you may be able to tell, I'm mechanical...)
A few clarifications (and I apologize for being so lengthy - just trying to give you guys all the details...) The "soft start" we installed was actually a Toshiba VFD. We had a reputable...
We have a 2250 HP 4160V 3P 60Hz 1.15SF 270FLA Induction motor on a large compressor. There are surge protectors and capacitors (GE 1.5uF, 3 Pole, 4160V) on each phase at the motor. The motor dropped out one day in the middle of unit operation - no alarms on the Multilin, no obvious signs of...
Thanks for the response. Ultimately we went for the purge. We installed a natural gas purge to each tap on the tower. At each tower tap, I installed a Brooks rotometer (vareameter) sized for 1/2-5 scfm. The DP's have now become a very reliable reading. You can only do this on towers that...
The level bridal has connections to flare, nitrogen, and isobutane flush. Also, our unit safety requirements state that a full acid suit (PPE) must be worn in this area. So calibration is a pretty safe operation.
The Fisher DLC3000 has a seal on it that segregates the electronics from the...
Source: SH-F1-20-A45-M3-S00-L0-P0
Detector: LJTH-36-V1-H0-M0-S00-P0
We are using this to detect the level in the HF regenerator column, so this is not an interface. We have tried using the internal radioactive type densometers in our settlers, but they were very problematic. These were...
Our process group would like DP's on the Atmospheric Crude Tower around every section. All DP's are in the vapor space of the tray. All the xmtrs are mounted above the taps with the sensor lines sloping toward the taps. I have steam traced the sensor lines, but we are still having problems...
We are in the process of installing an Ohmart source and detector on an HF column in our unit. The total installed cost looks to be about $20,000. The source and detector only cost around $7,000.
I would like to hot tap a few 1" connections on an existing tower to install some differential pressure transmitters. To install these hot taps, we would use a Sockolet with a nipple and a valve. My inspection department will not let me do these taps, even though ASME VIII allows it. The...
A DCS GUS is what Honeywell calls a "Global User Station". It is the acutal computer that interfaces between the IOP cards (Input Output Processors) and the Operator. The monitors that operators use to veiw and control the unit processes are connected to these GUS computers. The...
We have a TDC3000 utilizing Honeywell transmitters (instead of the before mentioned Rosemount). Loop check is a means to shorten the time for "cutover" (or actually commissioning the new instrument). During the loop check, the entire loop is connected from transmitter to DCS Gus...
We plan to replace some tubesheets in the convection section (1400°F to 1500°F) of a Reformer Unit heater with stainless steel. Someone mentioned that it is standard to use 310SS for these applications. The ASME Section II-D book indicates that 304SS plate has a higher allowable stress than...
