Leak Testing Specialists                    
        www.leaktestingspec.com                      
                                   
     Helium Pressurization and Cylinders Required  for a given He Concentration                    
  This worksheet will dertermine the Helium differential pressure increase needed to give the required concentration and the number of cylinders required.   Boxes in green are user required inputs, yellow boxes are the calculated results.                 
                                   
  Select Volume units:
                         
  Volume of container:                            
  % He concentration   % He                          
  Required test pressure:   psig                          
  Select type of cylinder to use:  
approx   cu ft air liters Empty Wt lbs                
  Cylinder fill pressure:   psig                          
  Volume of tracer required:   cubic feet                          
  He cylinder capacity:   approx   He cu ft   This decrease is due to Helium compressibility effects                  
  Pressurize with He to:   Differential pressure He addition (psid)                        
                         
                             
                                   
                                   
                                   
  US gallons   vol cu ft                          
  cubic feet         Brad's calc on bottles for 300  (neglects to subtract last atm of He in bottle))    
  liters   compressibility factor He @ 2000 psig   Brad's calc for 100 (same issue)       cu ft 300 psig Apx wt lbs
  cubic meters   vol for he         R 20 11   T 300 291 139  
      cylinder vol       RR 40 24   K 200 219 117  
                  Q 80 46   S 150 139 61  
      300 psig decrease         LD 122 58   M, LD 125 110 58  
      vol left 300         S 150 61   Q 80 81 46  
      no bottles       K 244 113   60 60 58 29  
                  T 330 139   RR 40 40 24  
      100 psig decrease                 R 20 20 11  
      vol left 300                          
      no bottles