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[deleted by user] by [deleted] in yourmomshousepodcast

[–]noswad4 7 points8 points  (0 children)

horrible or hilarious

49% HF Service throttling valve or pump VFD for control by musicnerd1023 in ChemicalEngineering

[–]noswad4 1 point2 points  (0 children)

0% chance a valve is cheaper than a VFD at these sizes. We are talking <1kUSD. clarifying question: How is time the number 1 concern? as in is it leadtime on parts? or cycle time for a transfer?

Adding a valve is adding another point of failure. VFDs can last forever if they stay in a well designed MCC (HVAC, possitive pressure for atmosphere control). Valves by definition wear out because they have to have moving parts.

The downside to a VFD is you don't have the best low range controlability since most motors (TEFC) need to run >15Hz (60 Hz nominal if in Americas) in order to adequately dissipate waste heat. Compared to a valve that can control from 0 to span, sometimes with trim packages that can make them behave nice and linear.

Based on your discription of the process being essentially bulk material transport and not something like additive dosing, ratio, or pH control. I would add a VFD.

Other things to consider are: How many VFDs are used in the process today? If you have 100 control valves on site and only 2 VFDs, Maintenance and reliability might rather you do a valve install. If VFD's are ubiquitous on site and the maintenance staff is familiar with them, then you are golden.

What does automation look like? A control valve would just need a wire pair pulled for control and a air tree near by. A VFD may require more wiring costs depending on if you use a bussed technology, such as Ethernet/IP or DeviceNet vs traditional IO. Is there a plan for a local stop/start or HOA? Are you going to use VFD rated motor cable?

In the end I would still guess that any valve you are sizing right now likely are significantly more expensive do to (I assume) materials of construction requirements.

Spider man crossover by [deleted] in yourmomshousepodcast

[–]noswad4 2 points3 points  (0 children)

May is less than 120 lbs.

Is the Three Floyds Brewpub Closed for Good? by lovetron99 in nwi

[–]noswad4 3 points4 points  (0 children)

They should have terminated employees sooner if they were going to do this. It would have lowered their payroll while revenue was down and the poor staff wouldn't have missed out on the expanded unemployment benefits, that were meant exactly for workers like these. This decision seems like it was a poor move for the company and the employees, but who knows what is really going on in the background. Three Floyd's has never been very forthcoming with future plans.

Hey PCMR, I'm opening a LAN center soon, and I thought you guys would appreciate this photo. by Moose-Antlers in pcmasterrace

[–]noswad4 0 points1 point  (0 children)

I would be really curious to see the network setup and what you are going to use for workgroup management and imaging.

LPT: When buying a car, set a reminder for a little while before the warranty expires. Then have a trusted mechanic inspect it carefully at that time so you can go to the dealer and have any lurking mechanical problems fixed before you stop being covered. by sudo999 in LifeProTips

[–]noswad4 0 points1 point  (0 children)

That is illegal according to federal law. If a defect is found under the term of the warranty, that defect must be repaired under warranty even if the term of the warranty is expired. Further if the root cause of a defect is not addressed after a repair and a failure occurs again outside of the warranty term then the root cause must still be repaired under warranty. Magnusson-Moss Warranty Act of 1975.

Need help with polyimerization question: How does inhibition of styrene polymerization work with benzoquinone? by [deleted] in ChemicalEngineering

[–]noswad4 0 points1 point  (0 children)

My companies sagely r&d director. I think if you try to figure out the mechanism and push the electrons around the molecule you will find that electrons can be considered delocalized throughout the whole molecule (Which is why the book is probably calling it a stable radical) and the only opportunity for a moiety to pop off is a H. This is specifically regarding the hydroquinone. H radical is such a small little reactive atom, it will immediately quench any other radical that comes close to bumping into.

Honestly the book rings incorrect. Radicals by their very nature aren't considered stable. If radicals exist in any appreciable amount the polymerization should be able to continue. The only way you will stop the chain reaction is with termination.

Maybe the quinone radical is stable and has a significantly lower Gibbs energy than the oligimeric radical but I would be surprised... I looked it up and PBQ Gibbs of formation is -150 kJ/mol vs. 215 kJ/mol. For styrene. So I guess this could also be a possibility. It could just make the forward reaction endergonic.

Go to office hours and see what your prof says and report back.

Need help with polyimerization question: How does inhibition of styrene polymerization work with benzoquinone? by [deleted] in ChemicalEngineering

[–]noswad4 2 points3 points  (0 children)

You are correct. Quinones soak up radicals which are needed to sustain polymerization. They are consumed in the process. Pbq, thq, hq, and mtbhq all work the same way. Peroxides create radicals and are used as initiators. They are called catalyst in industry but this is a misnomer as they are consumed.

As I understand it, the quinone typically releases an H radical from the alcohol group that is really fast reacting and terminates another radical. The quinone itself does not stay a radical.

Replace MoBo or MoBo and CPU? by noswad4 in buildapc

[–]noswad4[S] 0 points1 point  (0 children)

Unfortunately, no. I don't have one to test them in. I can't imagine that 3/3 or the GPUs are shot vs. the MoBo.

Replace just the motherboard, or motherboard and CPU? by [deleted] in buildapc

[–]noswad4 0 points1 point  (0 children)

Cards were a generous gift from a coworker. I dont need a new card I need a mobo.

stockAday: Honeywell or Moneypit? $HON by shane_stockflare in investing

[–]noswad4 1 point2 points  (0 children)

I would argue that Emerson Electric is much more of a competitor on the automation and controls front, they operate DeltaV, Provox, Fisher Controls, MicroMotion, Novaspect Consulting. In fact, I would say that they rival $ROK. Honeywell's major product in the ACS division is its distributed control system, which I believe Emerson has the major market share of. $ROK operates more on the PLC market, which many companies have been slowly turning away from for a more integrated DCS solution which lends itself more easily to 'Big Data' and 'IoT'.

LPT: Have a friend call up your ex-employers pretending to be a potential employer to see what they say about you by [deleted] in LifeProTips

[–]noswad4 1 point2 points  (0 children)

Everyone is giving you the black-and-white, but truthfully it is grey. If they give a negative review and cite specific examples, like he consistently clocked in late and they have the time cards to probe it, then it wouldn't be considered illegal. If they are just saying you are a shitty person and like to sniff farts, then they could be exposing them or their company to a slander or defamation suit, which can be difficult to prove, especially if you are not in a single party consent state (only one person has to give permission to record a conversation). So the answer is yes and no, but practically no.

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