KIPS 5

[darron]

I am drawing a blank in converting a KIP into a load specvified in Kn.

Can anyone supply a ratio or give me a clue0n how to convert

 

[Denial]

Older engineers will remember (with a shudder) that a kip is just 1000 pounds-force.

 

[Ingenuity]

darron,

1 kip = 1,000 lb-f = 4.448 kN

HTH

 

[BigH]

Focht3: to this Bowles is right!!!!

and, I thought that kip was the name given to Laos currency!!!

 

[DaveVikingPE]

Converting to metric is easy!

A Kip is a Kilo-pound.

A hip is a hecta-pound.

A mip is a millipound.

A dip is a decipound.

A cip is a centi-pound.

Have phun!

 

[hernma]

Ingenuity is correct: 1 Kip = 4.45 kN.

Here, some additional information:
1 pound (lb) = 453.59 grs, or 1 Kg = 2.205 lb
Kg = 9.80665 N = 2.205 lb, from where: 1 lb = 4.448 N
1000 lb = Kip = 4.448 N x 1000 = 4.448 kN

Kg/ cm2 = 14.223 psi
psi = 0.0703 Kg/ cm2 (this value is more exact)
N/m2= Pa ; and since: m2=(10)^6 mm2 ,(10)^6 Pa= MPa= N/mm2
MPa = 145 psi.

Now:
(f´c)^1/2, in psi= 1/145*(145 f´c)^1/2= 1/12(f´c)^1/2,MPa

Also:
(f´c)^1/2 , in psi = 1/14.22*(14.22 f´c)^1/2 = 0.265* (f´c)^1/2 , Kg/cm2

For example, vc = 2* (f´c)1/2 ,psi = 0.53* (f´c)1/2 , Kg/cm2 = 1/6 * (f´c)1/2 , MPa

Is this important ?. I think so, and for this reason I posted “Equivalence of units in ACI 318M-02” in the ACI Code Forum.

 

[chicopee]

That's good DaveViking...Our Canadian neighbords should really appreciate that as they have the tendency of mixing prefixes and suffixes in English and French.

 

[DaveVikingPE]

An e.u. is an "entropy unit." 1 e.u. = 1 cal/mol-K = 4.184 J/mol-K.

As far as the British using pounds vs. euros. I have no idea. Maybe they should all convert to talents. My air conditioner has a rating in Btu's and I haven't seen an Eu tu ("you too&quot air conditioner.

In all seriousness, I first heard the term "kip" in statics class many moons ago and was confused. During the evening's homework session, I looked it up (this was in the pre-web days) and made the "kilo-pound = kip" konnection. Whenever anyone asks me what a kip is (it happens a lot, really: I've had architects, ME's, EE's and even a couple of civil engineers not to mention the many laypeople ask) I tell 'em "it's a kilo-pound, get it? KIlo-Pound." That's the best way I've found to really explain it. In my first physics class metric (SI) was taught to us with a problem like "what's 2 x 10^2 withits?" Answer: 2 hecto-withits or "to heck with its."

US military design work is generally conducted using millimeters as the measure of length and kPa for pressure or area loadings; this is a pain as kPa simply is not an intuitive sounding unit of measure whereas kN/m^2 is.

 

[kenvlach]

DaveViking,
Right on, e.u. is an entropy unit &[ignore]equiv[/ignore]; cal/^oK/mol.

Same here, "I first heard the term "kip" in statics class many moons ago and was confused;" it was also where I first saw # as shorthand for pounds (force, not £).

Graduate school involved bars and MPa, but I stayed out of trouble by converting to atmospheres.

 

[LeoSC]

I have worked in SI and imperial units for 25 years, sometimes on the same project. I found a calculator that really helps conversions, called Calc98, somewhat of an electronic handbook table. You can download it from

http://www.calculator.org

You need to know the basic units, but the calculator takes it from there.

 

[trainguy]

Could someone please tell me why so many mech. engs refer to streses in psi as opposed to the much friendlier ksi ( kips per sq. inch )?

The FEA result may say that stress is 32000 psi, and I have to compare with the yield of A36 steel... I know it's really easy, but it just gets to me. Stress analysis is hard enough without the extra hurdles.

tg

 

[bluesman]

Each Time I come along such discussion it never fails to surprise me that with all the advancement in the engineering technology today, the world is not yet able to really use one unit system that can be applied everywhere!
I don't really see the point in sticking with prejudice to an out dated unit system such as the inch-pound system (the so called empirical) that was good enough to be used in times when precision meant nothing.
I know engineers in the US , UK and some other countries may disapprove with me but come on guys, make way for the 22nd century!!!



Drop By !!

http://www.geocities.com/concretesite

 

[Sparweb]

While were converting units between different systems:

It is commonly known that time is money, and knowledge is power. It is not so commonly known that these relations have a strong impact on the structure of our society. Hence:
[ul]time=money[/ul]
[ul]knowledge=power[/ul]
These relations can easily be substituted into the tried and true equation of work and energy:
[ul]power=work/time[/ul]
Therefore:
[ul]knowledge=work/money[/ul]
Solving for money:
[ul]money = work / knowledge[/ul]
Conclusions:
[li]The more money you want to make, the more you need to work (no kidding)[/li]
[li]The more knowledge you gain, the less money you can expect to make[/li]
Going back and putting "time" back in, it is clear that we work overtime only when we've done something dumb.
Also, those with the most power get there through doing the most work, but I disagree that they didn't also do it for the money.


STF

 

[Ingenuity]

The USA and only two other countries (Liberia (in western Africa) and Myanmar (also known as Burma, in southeast Asia)) have not officially adopted the metric system. Fascinating!

It is also fascinating is that the US Federal government (at least engineering and construction for the DOD) IS metric, but much (most!) of the USA is not.

Metric is "10 times" better!

 

[Lutfi]

I am not going to argue the merits of each system. However, one must appreciate the tremendous resources and cost that the US will have to go through to change over to metric. Tools, machines, books, references, measuring tapes, not to mention the interface with existing systems and components are few of the things that must change to name a few..

I had the pleasure of working with an older British Engineer whom I have immense respect. He does not think that the metric system did not do wonders for the UK and they do use it.

The argument can be made for both systems. I think engineers should be trained and capable of using both systems.

 

[Ingenuity]

But the US trading partners use the metric system. Unless the USA is going to significantly increase trade with Burma or Liberia, then it makes sense for the USA to finally and officially change to the metric system.

Maybe the fact that the French "invented" the system has something to do with the USA not adopting it. [LOL]

I have used both measurement systems in Australia, Canada and the USA. Metric "wins" IMO.

The $125 million NASA Mars Climate Orbiter mission may not have been "lost" in 1999 if the USA was fully and officially metric.

For the merits on the metric system, see the US Metric Associations FAQ's at:

http://lamar.colostate.edu/~hillger/qanda.htm

 

[Qshake]

For my $0.02

I have used both systems since grade school and continued to do so in my work now.

I really don't see the problem with using one or the other and why engineers of all people vehmently oppose the use of the metric system.

I do agree that it is logical to follow the units of world trade. However, the system seems to work despite the three countries who are holding on the english units.

 

[rapt]

As soon as people started using mechanical and electronic calculators the logic of using the imperial system of units was lost and everyone should have changed to the SI system.

To work logically on computers, decimal feet is the only way they can work internally and is also the easiest input method. Having to perform convoluted calculations just to convert feet, inches and fractions of an inch to decimal feet for input or for use in calculation is just plain stupid (there are 4 mathematical steps to do this, 4 mathematical symbols need to be input plus more numerical characters are required than for SI) when you can use a system where there are no such divisions, SI. m, cm or mm make like so easy for the person doing the input and for the program itself internally, simply move the decimal point to change between them.

It must have been horrendous using a slide rule or an abacus with imperial length units and it is nearly as bad with electronic calculators.

USA is not the only country thet would have to suffer a conversion process and the hassles with it. Australia, UK and Canada did it and so did many others and we all survived the experience and now I am glad we did. The SI system is much easier to work with, especially length units.
Fortunately this is one USA will not win in the long term, SI is the worldwide unit system and a couple of intransigent countries have not moved to it yet.

 

[Neilmo]

Hi all,

Like Qshake, I have used both imperial and SI units. At college (many years ago), I did an Ordinary National Certificate in Mechanical Engineering (in the UK) and the units were all imperial at that time. Later I went on to do a Higher National Certificate, but by this time the UK had gone metric and the units were SI. I have used SI units ever since and they are so much easier to handle. All the 10^6 and 10^3 etc. cancel out and you are left with just a simple sum to calculate. With the imperial system however, there is all that, divide by 12 to convert inches to feet and 1728 to convert cubic inches to cubic feet - what kind of numbers are those!! - to complicated!!

Keep it simple (KIS).

In reply to Lutfi - `cost of change over`. Although in theory the UK went metric 25 or 30 years ago, many of our steel sizes are in reality, still imperial sizes. Consequently we have steel `I` beams of, for instance, 457 x 191. This may sound an odd metric size (and it is), but is still, even after all these years, the old imperial steel rolls just converted to metric numbers (18" x 7.5&quot. Yes, many of our steels are still imperial in reality!! As you say, to expensive to change everything at once.

Regards,
Neilmo

 

[jheidt2543]

A few additional thoughts:

1. In the US, who are the major proponents of going Metric? Those in the machine tool industry, the industry that will benifit the most because of the retooling required.

2. Ingenuity, from what I've read, the loss of the Mars Orbiter was due to someone using the wrong conversion factor between the Imperial and Metric systems. The person reviewing the Metric answer could not conceptualize the answer. We engineers rely on our ability to know what psf and psi mean physically. We loose that when we go to Metric units. I've seen too many mistakes made trying to convert units, even in some of the trade journals!

3. State DOT's have been converting to Metric measurements, why? We don't trade the roads with a foreign county! In fact, many of the DOT's have given up on the Metric conversions of reinforcing steel, it was just too confusing and lead to too many mistakes.

Use the conversions when you HAVE to, but leave those of us old fuddy-duddies who don't want to ALONE!