440 THE HANDBOOK FOE PRACTICAL FARMERS 



Propobtionats Head of Fall Giving Highest Efficiency in Operation of 

 Hydkaulic Rams 



*Any size ram may be operated under these conditions and will afford the following 

 approximate delivery : 



No. 



2 requires 



3 " 

 4 



5 



2 to 3 gals, per minute and will deliver 



2 to 4 " 



3 to 7 " 

 6 to 12 " 



11 to 20 " 



18 to 35 " 



30 to 60 " 



Installing the ram. — As a general rule, there should be one 

 foot of fall for each seven feet of elevation ; the ram should never 

 be installed under less than three feet of fall, as this is the 

 smallest fall under which it will operate. The fall between the 

 source of supply and ram should not be greater than specified 

 in the table above, as a greater fall causes an unnecessary strain 

 on the ram and piping, and will interfere with the operation of 

 the ram. 



Both the drive and discharge pipes for the various ram sizes 

 should have the diameters given in the tables, page 114; the 

 length of the drive pipes should be the same as the vertical 

 heights the Avater has to be lifted. For example, if the water has 

 to be lifted a vertical height of forty feet, the drive pipe should 

 be forty feet in length. When a double ram is installed it 

 should be remembered that a separate drive pipe is required 

 for each of the two rams. 



Sometimes the lay of the land is such that it is impossible to 

 get the required amount of fall for the drive pipe within the 

 length the drive pipe should be according to the preceding rule. 



* It is assumed that the smaller rams will not be selected for extremely high lifts, 

 as the friction loss of water in a small drive and discharge pipe renders their use 

 impracticable. 



Where water supply will permit, always select ram of ample size for requirements. 



