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Courses in US: SI vs. Field units

Courses in US: SI vs. Field units

Courses in US: SI vs. Field units

I am offering few courses in the oil industries for engineers here in Canada from four years ago. Now, I am planning to offer them in the States(TX)in near future and I want to do the required changes in my presentations. Regarding Units, do I need to get rid of all SI units and put them in field units or keep them both. I have the below options:
Canadian type: 1 m
American type, option 1: 1 m (3.28 ft)
American type, option 2: 3.28 ft(1 m)
American type, option 3: 3.28 ft

Which one do you believe is better?

RE: Courses in US: SI vs. Field units

For text I've found that it is best to just go through the slides and add a parenthetical to the other units (your option 2 seems to go over best everywhere). Something like:
  • "As pressure decreases below about 45 psig, most equations ...
  • Becomes "As pressure decreases below about 45 psig (3 bar), most equations ...
Nobody seems to hate that very much, and I was quite surprised at how few times I actually mentioned specific numbers in a 700 slide course. The hardest thing was tables (there often just isn't room for the parenthetical trick), and I ended up having to duplicate several tables, leaving both in the slide pack and telling the students to use whichever made more sense to them

Volume flow rates for gas is the toughest unit. Everyone in the world seems to understand SCF, but when I use the Canadian E3M3 nobody outside Canada understands. If I use the Australian conversion to energy a couple of countries get it, but most don't. One guy in Germany wanted to use (km)^3, but that caused so much confusion. I finally settled on SCM (and defined the temperature and pressure I used for "standard" at the beginning), which seemed to irritate the fewest people.

For graphs of pressure vs. other stuff I set the minor axis at 14.5 psi=1bar=100kPa, and the major axis at a convenient multiple of 14.5 psia and leave the scale in psia. That way people who work in bar can just count the lines, people who work in kPa can count the lines and add two zeros, people who work in kgf/cm^2 can continue to guess. That has been very well received.

Basically, even in Texas most Engineers can stumble through unit conversions, you are trying to get concepts across not basic arithmetic. For my 5-day class I encourage the students to buy Uconeer and have it running while I'm talking. It is when you are presenting to non-Engineers that they get snotty if their units are not first.

David Simpson, PE
MuleShoe Engineering

"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.

RE: Courses in US: SI vs. Field units

Both - I was taught that way almost 40 years ago!!

RE: Courses in US: SI vs. Field units


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