Fig. 44.—Installation of ram.
Usually the water is led from above the dam or waterfall in a pipe to the ram and flows away after passing through the ram, back into the stream. The water pumped is generally taken from the same stream and is a part of the water used to operate the ram. This is not necessary, however, and double-acting rams are manufactured which will pump a supply of water from a source entirely different from that which operates the ram. The following table from the Rife Hydraulic Engine Manufacturing Co. gives the dimensions and approximate costs of rams suitable for pumping against a head not greater than about thirty feet for each foot of fall available in the drive pipe:—
TABLE XI
| Dimensions | ||||||||||
| Number | Height | Length | Width | Size of Drive-pipe | Size of Delivery-pipe | Gallons per Minute required to operate Engine | Least Feet of Fall Recommended | Weight | Price Single-acting | Price Double-acting |
| 10 | 2' 1" | 3' 2" | 1' 8" | 1-1/4" | 3/4" | 2-1/2 to 6 | 3 | 150 | $ 50 | $ 65 |
| 15 | 2' 1" | 3' 4" | 1' 8" | 1-1/2" | 3/4" | 6 to 12 | 3 | 175 | 55 | 70 |
| 20 | 2' 3" | 3' 8" | 1' 9" | 2" | 1" | 8 to 18 | 2 | 225 | 60 | 75 |
| 25 | 2' 3" | 3' 9" | 1' 9" | 2-1/2" | 1" | 11 to 24 | 2 | 250 | 66 | 81 |
| 30 | 2' 7" | 3' 10" | 1' 10" | 3" | 1-1/4" | 15 to 35 | 2 | 275 | 75 | 90 |
| 40 | 3' 3" | 4' 4" | 2' 0" | 4" | 2" | 30 to 75 | 2 | 600 | 150 | 170 |
| 80 | 7' 4" | 8' 4" | 2' 8" | 8" | 4" | 150 to 350 | 2 | 2200 | 525 | 575 |
| 120 | 8' 9" | 8' 4" | 2' 8" | 12" | 5" | 375 to 700 | 2 | 3000 | 750 | 850 |
| 120 | 8' 9" | 8' 4" | 2' 8" | 2-12" | 6" | 750 to 1400 | 2 | 6000 | 1500 | 1700 |
If the length of the discharge pipe is more than a hundred feet, the effect of friction is to reduce the amount of water pumped, but rams will operate successfully against a head of three or four hundred feet. The writer remembers an installation in the northern part of New York State, where two large hydraulic rams furnish the water-supply supply for an entire village, pumping every day several hundred thousand gallons. Figure 44 shows an installation by the Power Specialty Co. of New York, using the fall of some rapids in a brook to pump water into a tank in the attic of a house.
Fig. 45.—Means of securing fall for hydraulic ram.
In Fig. 45 are shown two methods of securing a fall for hydraulic rams, recommended by the Niagara Hydraulic Engine Co. The first method shows no drain pipe, but a long drive pipe; while the second method puts the ram in an intermediate position, with considerable lengths of each.