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equations
5

equations

equations

(OP)
im just starting to become a Pump engineer and i need to know Pounds per square inch (PSI), BAR, Mbar, Kilo Pascal (Kpa), Pascal (Pa) and Meters head (M) – Find out the conversions to make one equal the other. can anyone help me with this

RE: equations

eFunda.com

RE: equations

Do a Google search for unit conversion

cheers

RE: equations

Look in the front of machineries hand book or similar text book.

Heck, some diaries will give some of these.

KENAT, probably the least qualified checker you'll ever meet...

RE: equations

I like convert.exe, which can be downloaded from the mother web, it gives a wide range of unit conversions.

RE: equations

There are a couple of convert.exe out there.

I had a really good one back in the UK, I've never found it again.  The one I found now on the web isn't as good.

KENAT, probably the least qualified checker you'll ever meet...

RE: equations

Of just use Google.  You can, for example, enter "convert 25 bar to psi" and Google will give you the answer.

Works for currency too.

RE: equations

That I think is the one I had in the UK, awesome, thanks TenPenny!  Star for you.

KENAT, probably the least qualified checker you'll ever meet...

RE: equations

Also, get yourself a copy of Crane 410.  It's not about pumps, but it is THE definitive reference for flow through piping systems.

RE: equations

Another good resource is the Gould's Pump Manual. At least in the older versions, there's a section in there all about technical resources for pump engineers.

RE: equations

(OP)
hey thanks for the help guys!!

RE: equations

(OP)
Description of flows:-
Liters a second (l/s), Meters cubed an hour (M3/hr), gallons per minute imperial, gallons per minute US

can someone help with this please i got a rough understanding but still not quite sure thanks again

RE: equations

(OP)
Glanded / Glandless pumps what is the difference iv been told that one can deal with hotter water but not 2 sure if its ture or not  

RE: equations

The best thing is to understand the units you are working with and where they come from. Then you will be able to work with any units you like instead of having to constantly convert backwards and forwards.
All that is required is that you enter appropriate units when something is defined, and that you specify the required units when retreiving information.

For example:

CODE

      REM PROGRAM
      REM -------
      
      pressure = 760 * mm * of_mercury * on_earth
      
      PRINT "Pressure is " pressure/atm " atmospheres"
      PRINT "Pressure is " pressure/bar " bar"
      PRINT "Pressure is " pressure/millibar " millibars"
      
      PRINT "Pressure is " pressure/psi " psi"
      PRINT "Pressure is " pressure/(foot*of_water*on_earth) " feet of water"
      
      flow = 10 * litre/s
      
      PRINT "Flow is " flow / (gallon_US/minute) " US gallons per minute"

In order to do that, you need to understand and be able to define the units you are working with, eg

CODE

      REM Written in BBC BASIC - will run on free demo version from here:-
      REM http://www.cix.co.uk/~rrussell/products/bbcwin/bbcwdemo.exe
      *FLOAT 64 : REM Precision for real number arithmetic
      
      REM Define Units
      REM ------------      
      
      kg=1 : m=1 : s=1
      deci=1/10 : centi=1/100 : thousand=1000 : milli=1/thousand : kilo=thousand : mega=thousand*kilo : giga=thousand*mega
      mm=m/thousand : dm=deci*m : cm = centi*m : km = kilo*m
      cm2 = cm*cm : m2 = m*m
      m3 = m*m*m : litre = dm*dm*dm : cm3=cm*cm*cm
      gram=kg/thousand
      
      minute=60*s : hour=60*minute : day=24*hour
      inch=2.54*cm : foot=12*inch : yard=3*foot : chain=22*yard : furlong=10*chain : mile=8*furlong
      inch2=inch*inch
      inch3 = inch*inch*inch
      
      mph = mile/hour
      kmh = km/hour
      
      N=kg*m/s/s : Pascal=N/m2
      bar = 100*kilo*Pascal : millibar = milli*bar
      
      atm=101325*Pascal
      
      lb = 0.45359237 * kg : REM http://en.wikipedia.org/wiki/Pound_%28mass%29
      
      REM gravity
      g = 9.80665 * m/s/s : REM http://en.wikipedia.org/wiki/Standard_gravity
      on_earth = g
      on_moon = 0.1654 * g : REM http://en.wikipedia.org/wiki/Moon
      
      REM density
      of_water = 1000*kg/m3
      of_mercury = 13.534 * gram/cm3 : REM http://en.wikipedia.org/wiki/Mercury_%28element%29
      
      lbf = lb * g
      
      psi = lbf / inch2
      
      gallon_US = 231 * inch3
      gallon_UK = 10*lb / of_water : REM Volume of 10 pounds of water

Then, if you want to measure pressure in fully fueled jumbo jets per acre, or measure flow in cubic light years per millenium, it isn't a problem.

RE: equations

Wow, I remember BASIC.  Then I started shaving.

- Steve

RE: equations

Okay, in PHP then, allowing one to display the results of calculations in web pages and look knowledgeable, without actually having done any hard work by hand, ....

An object is in freefall for 3 micro-minutes. What is its speed in furlongs per fortnight?

Quote (Program):


$g = 9.80665 * $m/$s/$s;

$speed = 3*$micro*$minute * $g;
echo "Speed is ", $speed/($furlong/$fortnight), " furlongs per fortnight.";

displays

Quote (Display):


Speed is 10.6139261274 furlongs per fortnight.

Once again, you need to understand your units but complicated units are usually defined in terms of simpler ones, eg miles per hour, cubic feet per minute, pounds per square inch, etc.

Quote (Unit_Definitions):


$inch = 2.54 * $cm; $foot=12*$inch; $yard=3*$foot; $chain=22*$yard;
$furlong = 10*$chain; $mile=8*$furlong;

$minute=60*$s; $hour=60*$minute; $day=24*$hour; $fortnight=14*$day;

This time I have omitted plenty of definitions, but it should be clear that once an effort has been made to understand a new unit it can easily be used.

Nowhere above did we actually worry our own little heads about 'what is the conversion constant between speeds in
 micro-minute metres per square second
, and furlongs per fortnight ?' (Luckily!)

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