What's a kilopascal?

[Tom Bender]

A kilopascal is a measurement of pressure, similar to psi. It's a commonly used metric term, but for the mechanically minded it is not clear, like grams per square centimeter would be. Atmospheres (bar) is useful also. For a rocket scientist, kilopascal is more convenient when working in places other than the surface of the earth or to high precision. For me a useful number is that a psi equals about 7 kilopascals. I like the metric system, just not this particular convention.

[Rod Sheridan]

One Newton per square metre is easy to remember, however it’s a small unit hence the Kilopascal.

It’s sort of like when someone asks how much something weighs and then gives a figure in Kg….Should be in Newton’s.

Regards, Rod

[John Stankus]

Careful 1 bar is not 1 atmosphere. It's close but not the same

1 atm = 760 mm Hg = 760 Torr = 101.325 kPa = 1.013 bar

1 bar = 100000 Pa = 100 kPa = 0.987 atm

Pa = N/m2 which means a kPa = 1000 N/m2 a square meter is a pretty big area, is we convert to cm2 this means a kPa = 0.1 N/cm2 if you want to extend that its about equivalent of the force exerted by gravity on 10 grams of matter in a square centimeter. Which means 1 atm which is 101.325 kPa is about equivalent to the force of gravity on 1 kg spread over 1 cm2

John (who is teaching the senior level Thermodynamics course this semester)

[Doug Garson]

Canada went metric, sort of, in the 80's. I went thru school using mainly the imperial system and still feel more comfortable with it. I remember when the metric system was introduced at work in an engineering office of a boiler manufacturer but the vast majority of the projects I did in the boiler and power generation industry were still imperial. Today, the only metric measurement I feel more comfortable with is the kilometer for driving distance. A kilometer is roughly ten football fields excluding the end zone so it's easy to picture. I can't picture how many football fields in a mile. Just looked it up, it's around 17 1/2 football fields, ten is easier to remember.
Kilopascal? No feel for it.

[Bob Turkovich]

Canada went metric, sort of, in the 80's. I went thru school using mainly the imperial system and still feel more comfortable with it. I remember when the metric system was introduced at work in an engineering office of a boiler manufacturer but the vast majority of the projects I did in the boiler and power generation industry were still imperial. Today, the only metric measurement I feel more comfortable with is the kilometer for driving distance. A kilometer is roughly ten football fields excluding the end zone so it's easy to picture. I can't picture how many football fields in a mile. Just looked it up, it's around 17 1/2 football fields, ten is easier to remember.
Kilopascal? No feel for it.

Which football field do you use? American, Canadian or Association (soccer)?:p

[Doug Garson]

Which football field do you use? American, Canadian or Association (soccer)?:p
There all ​about 100 meters long, Canadian football 101 meters (goal line to goal line), US football field 91.44 meters and Association soccer field 105 meters.

[Mike Henderson]

Canada went metric, sort of, in the 80's. I went thru school using mainly the imperial system and still feel more comfortable with it. I remember when the metric system was introduced at work in an engineering office of a boiler manufacturer but the vast majority of the projects I did in the boiler and power generation industry were still imperial. Today, the only metric measurement I feel more comfortable with is the kilometer for driving distance. A kilometer is roughly ten football fields excluding the end zone so it's easy to picture. I can't picture how many football fields in a mile. Just looked it up, it's around 17 1/2 football fields, ten is easier to remember.
Kilopascal? No feel for it.

The American military went metric long ago. I remember, back in the 60's, studying land navigation and all the maps were in meters. And we were taught to talk in meters and kilometers. The slang for a kilometer was "klick" (or "click"), as in "It's six klicks from here".

Mike

[Ken Fitzgerald]

I can remember in HS school in the 60's when the physic teacher told us we'd be going metric shortly. US medical field did go metric. Working on diagnostic imaging equipment, I carried imperial and metric tools as some of the older equipment still was imperial and the newer equipment required metric tools.

[Doug Garson]

Interesting Mike, I've heard the term klick but never knew it stood for kilometer, now that I know it makes more sense.

[Mike Henderson]

I can remember in HS school in the 60's when the physic teacher told us we'd be going metric shortly. US medical field did go metric. Working on diagnostic imaging equipment, I carried imperial and metric tools as some of the older equipment still was imperial and the newer equipment required metric tools.

It's funny how some things when metric, like large bottles of soda (a liter) or liquor (750 mL), but other things have not. Cars certainly have gone metric.

But miles and Fahrenheit are still with use rather than kilometers and Centigrade. And inches rather than centimeters.

Mike

[Rod Sheridan]

Same here, we use metric for volume, mass, distance, temperature and pressure, yet pipe is still Imperial, as is the length and width of plywood, but not the thickness.

Weird mix of systems……Rod.

[Ole Anderson]

Interesting how all of the Canadian home improvement shows mix their units. A 2x4 is seldom called by it's metric equivalent.

[roger wiegand]

Well a "2x4" is a name for a board of an approximate size that has nothing to do with measurement. Sizes vary all over the place, and it's been a century since they measured anywhere close to 2" x 4", before or after sanding.

[Don Coffman]

Before retiring I was a process safety engineer working for a large consumer products company with manufacturing sites across the globe. I developed/maintained engineering calculation applications in MS Excel for fluid flow, strength of equipment, relief, explosion venting etc. in imperial as well metric. When I started adding the metric capability, it was found small conversion programs were invaluable.

[Curt Harms]

One Newton per square metre is easy to remember, however it’s a small unit hence the Kilopascal.

It’s sort of like when someone asks how much something weighs and then gives a figure in Kg….Should be in Newton’s.

Regards, Rod

Any relation to Fig?;) That's the only Newton most Yanks are going to be familiar with. I get along reasonably well with many metric measures but Newton just doesn't compute for me. Aircraft engine output is often expressed as pounds of thrust or KiloNewtons. There are of course online converters but that's one unit of measure I have trouble getting my head around.

[David L Morse]

Any relation to Fig?;) That's the only Newton most Yanks are going to be familiar with. I get along reasonably well with many metric measures but Newton just doesn't compute for me. Aircraft engine output is often expressed as pounds of thrust or KiloNewtons. There are of course online converters but that's one unit of measure I have trouble getting my head around.

I find Newtons to be less confusing than poundals, slugs, poundmass and poundforce.

[Alan Lightstone]

... US medical field did go metric.

It's funny, though. Every doctor I know has an intuitive feel for metric weights in kg. But list a height in cm, and we all reach for our calculators to see how tall that is.

I always spoke to one of our English surgeons about how many stones the patient weighed. He always got a chuckle out of that.

[Bill Dufour]

Whats the question? Did the first post get deleted?
A kilopascal is 1000 regular pascals.
Bill D

[Lee DeRaud]

For me a useful number is that a psi equals about 7 kilopascals.Kilopascal is a unit of measure designed solely to scare you into thinking your tires are going flat.

This happens when the digital gauge which normally displays "32.0 PSI" starts displaying "220 KPa". In both cases, the unit and the decimal point are far too small to see in a dimly-lit garage. By the time you figure out what's going on, you've turned on the compressor, pulled out the hose, and pumped up the tire to 46PSI or so. DAMHIKT.

The gauge in question now has a double layer of duct tape over the button that changes units.

[Mike Henderson]

Kilopascal is a unit of measure designed solely to scare you into thinking your tires are going flat.

This happens when the digital gauge which normally displays "32.0 PSI" starts displaying "220 KPa". In both cases, the unit and the decimal point are far too small to see in a dimly-lit garage. By the time you figure out what's going on, you've turned on the compressor, pulled out the hose, and pumped up the tire to 46PSI or so. DAMHIKT.

The gauge in question now has a double layer of duct tape over the button that changes units.

That's a really funny story. I'll watch out for that.

Mike

[Rod Sheridan]

I find Newtons to be less confusing than poundals, slugs, poundmass and poundforce.

Exactly, I’m always lost with the imperial system.

[Tom Bender]

Hi Rod
The only place poundals, slugs, pound force and pound mass are to be found is in textbooks. They are arcane. PSI is found and understood everywhere in north america. Newtons, not so much.

[David L Morse]

Hi Rod
The only place poundals, slugs, pound force and pound mass are to be found is in textbooks. They are arcane. PSI is found and understood everywhere in north america. Newtons, not so much.

To me psf is more intuitive than psi.