Hydraulic Rams; Their Principles and Construction (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1907 Excerpt: ... is a diagram showing the compression curve of the air in the vessel under pressures extending from 1 to 5 atmospheres above the normal; one atmosphere of pressure being taken at 30 in. of mercury and at a temperature of 60 Fahr. Two atmospheres of pressure--that is, one above the normal--reduces the air to half the space; three atmospheres, or 2 above the normal, reduces the air to one-third the space; and so on for other increases of pressure. By the aid of the diagram the extent of the air compression in the vessel can be noted. The height to which the ram is raising water can also be seen at a glance, either by readings taken from the pressure gauge or by noting the level of the water in the glass gauge attached to the side of the vessel. Also by the aid of the diagram any small mistakes made when taking observations are easily corrected, and intermediate readings found without having to make tedious arithmetical calculations. CHAPTER XII Experiments To Find The Duty Of A Ram Under Varying Conditions Experiment III With the drive-pipe D (see Fig. 14) and with a flying start; that is, the records were not taken until the pressure gauge stood steady. Each test was timed to 4 minutes. It should be noted that although the first two items show a like number of valve beats as having taken place in the same period of time, the second one gives a larger quantity of water both used and raised. The height of the delivery is also greater, and a higher percentage of duty thus obtained. In these two experiments the dash-valve opened only a very short distance, but as the height of delivery was increased, the stroke lengthened, and when beating 112 and 110 strokes per minute, the valve opened to the full extent. But the force of the falling water was not sufficient t...