	\B2.0  USING 'ISO'\b

	\BSTEP 1:\b
	  Install the program:

	  a) DOS version:
	     Put the program diskette in drive A and type: A:\\INSTALL
	     This will install the DOS-programs in directory C:\\ORIFICE
	     or show you how to install the program in a directory of your 
	     choice.

	  b) Windows version:
	     The Windows version of the program uses the Visual Basic 3.0
	     runtime DLL.  Put the program diskette in drive A.  From 
	     the Microsoft Windows Program Manager, choose RUN from the 
	     FILE menu and type: A:\\SETUP or double-click on the SETUP.EXE
	     file in drive A.  Setup will copy the program to directory
	     C:\\ORIFICE unless you make your own choice.  If you want the
	     program-icon to appear in another group window, move it to 
	     where you want 'ISO' to be and delete the window group 
	     made by Setup.  Save your selections.

	  \BSTEP 2:\b  Start the program by typing "ISO" from the DOS-prompt, 
		   or 'click' on the correct icon:

				FLOW -ORIFICE

			FLOW-ORIFICE CALCULATION PROGRAM

			International Standard ISO 5167-1:1991  
	-------------------------------------------------------------------

		 Copyright (C) 1996 by B. K. Berge (Version 4.0)


	  The Disclaimer is shown before the main menu appears: 

		      Gas Orifice
		      Liquid Orifice
		      Restriction Orifice - Gas
		      Restriction Orifice - Liquid
		      EXIT


	  \BSTEP 3:\b Calculation Options:

	  After choosing type and method of calculation the input-screen 
	  will appear.  For gas-calculations you have to enter specific 
	  gas gravity, temperature and pressure.  You can also give 
	  molefractions of N2, CO2 and H2S for sour gas calculations.

	  The AGA-8 equation is used for calculating Z-factor 
	  (compressibility factor) for natural gases.  The equation is
	  complex, and calculation time may be long depending on your 
	  computer-type.  The Redlich-Kwong equation of state is used 
	  for air and nitrogen.

	  For oil-calculations you have to enter specific oil gravity, 
	  temperature and pressure.  It is also recommended to give
	  molecular weight of oil.  For water-calculations the input 
	  requirements are salinity, temperature, and pressure.
	  NOTE: It is assumed that all dissolved solids for water are 
	  expressed as equivalent sodium chloride concentration.  The 
	  results are an orifice specification sheet giving the necessary 
	  data for design of an orifice or evaluating an existing orifice.


	  \BSTEP 4:\b Interpreting the results:

	  The results will contain a few factors that you should know:

	  \UISO 5167-1:1991\u

	  The basic flow equation is:

		   Qm  = C*E*Eps*Pi/4*OD^2*Sqrt(2*dP*Roh)

	  where    
		   Qm  = Mass flow rate (kg/s)
		   C   = Discharge coefficient = Alpha/E
		   E   = Velocity of approach factor = 1/(Sqrt(1-Beta^4))
		   Eps = Expansion factor due to pressure drop
		   Pi  = 3.14159
		   OD  = Orifice diameter at actual flowing conditions
		   dP  = Differential pressure across orifice
		   Roh = Density of flowing fluid measured at upstream tap

	  
	  The flow coefficient is given above as:

			     Alpha = C * E

	  and the orifice to pipe diameter is:

			     Beta = OD/PID

	  The definition of the factors are given in Ref. 1.
