Kgf/cm2 vs Kg/cm2
Kgf/cm2 vs Kg/cm2
(OP)
We are getting inquires for pressure transmitters to be calibrated in Kgf/cm2 instead of our usual Kg/cm2. They seem to be exactly the same, but why are there diffent designators? How did it come about and why?
Thanks for any info.
Thanks for any info.





RE: Kgf/cm2 vs Kg/cm2
Hope this helps.
saxon
RE: Kgf/cm2 vs Kg/cm2
RE: Kgf/cm2 vs Kg/cm2
RE: Kgf/cm2 vs Kg/cm2
1 bar = 100 000 Pa = 100 kPa
1 torr = 1 mm Hg = 133.32 Pa
1 psi = 6894.8 Pa
1 atm = 101.325 kPa
1 in Hg = 3386.6 Pa
RE: Kgf/cm2 vs Kg/cm2
Have a better one.
saxon ;)
RE: Kgf/cm2 vs Kg/cm2
RE: Kgf/cm2 vs Kg/cm2
RE: Kgf/cm2 vs Kg/cm2
RE: Kgf/cm2 vs Kg/cm2
really we should get way from pressure and use elevation measurements. that would really "clear things up".
RE: Kgf/cm2 vs Kg/cm2
Adding to the confusion, we generally use the following pressure units.
Steam and water - kg(f)/cm2
Compressed air - psi
Vacuum - mm of hg, ultra low vacuum - Torr
ventillation system - mm of wc (regulatory authorities are asking for Pa now)
Just give us 100 more years after all you people start to use common system of units.
huh..I don't think any unit is left behind
By the way I am very good at conversion of units
Believe it or not : Goldbach's conjecture says any even number can be written as a sum of two prime numbers. Postulated in 16th century, nobody could, so far, prove it nor disproove it.
RE: Kgf/cm2 vs Kg/cm2
It is actually Kgf/Cm2 or Lbf/In2.
In practice we use KG/Cm2 or Lb/In2.
The derivation follows:
Pressure = FORCE / AREA
Force = Mass x Acceleration
= Lbm x g/gc
= Lbm x (ft/Sec2) x ((Lbf x Sec2/(Ft-Lbm))
Pressure =Lbm x (ft/Sec2) x ((Lbf x Sec2/(Ft-Lbm))/(ft2)
=Lbf/ft2 (OR)
=Lbf/In2
We say One Atm = 34 ft of WC,but it is 34 ft(f) only, derivation follows:
Head = Press/Density
= Lbf/In2/Lbm x In3
= Lbf x In/Lbm (OR)
= Lbf x ft/Lbm
= ft (as we say)
RE: Kgf/cm2 vs Kg/cm2
John
RE: Kgf/cm2 vs Kg/cm2
Gentlemen,
The fact is that the metric system has a separate unit for force, called the Newton (kg.m/s^2) while the, apparently revered, English system does not; so a unit of force in the English system is called a pound force (lbf) and is equivalent to lbm.ft/s^2. Simply to differntiate the two pounds.
There is an lbf and an lbm, while only 1 Kg.
In the Metric system, if you want to talk force, you use Newton - no confusion.
RE: Kgf/cm2 vs Kg/cm2
Oh would that it be so. If Newton's (and their companion Pascals) were universal, then we wouldn't be having this thread. I firmly believe that "kgf" is just a stupid as "slug" and I wish that instrument manufacturers would not accept orders for instruments calibrated in this abortion of a unit - except that instrument makers are not cops, and if one of us engineers ask for it and the first maker ssys "no" then the next will say "yes" and the first maker will have lost a sale and possibly a customer.
Engineers have to stop asking for stupid things before manufacturer's will stop making the stupid things.
David Simpson, PE
MuleShoe Engineering
www.muleshoe-eng.com
RE: Kgf/cm2 vs Kg/cm2
In UK, NPL also have paper to describe the relationship between kg and kgf.
RE: Kgf/cm2 vs Kg/cm2
the standard measure of weight and force was a platinum mass in a day when gravity was thought to be a constant,having no really precise way to measure force.
as a result the kgf and a related lbf, poundals, and slugs became common place.
just remember both cm mm as metric units do not comply with SI either. it is a matter of dogma or engineering, but at the end of the day it has to fit and work
RE: Kgf/cm2 vs Kg/cm2