LOW RATI automatically proportions two flows with high accuracy! If you h a v e a ratio flow control problem where you wish to keep one flow at a fixed percentage of a second variable flow, the new Rotamatic Ratio Flow Controller will do the job automatically for you. Furthermore the ratio m a y be varied a t viil by a turn of the flow ratio button. T h e device for doing this remarkable job of proportional control is so simple and so positive t h a t what was once a difficult control problem has become easy and also reasonable in price. In the flow chart shown above, the ratio index button has been set for proportioning a t 1:2. Notice how accurately this proportion has been maintained, in spite of rapid flow fluctuations and variations over t h e full flow range of the rotameters. The Ratio Controller operates as follows: Two rotameters witli electric transmission for remote reading a r e placed in the respective flow streams. T h e remote flow-responsive balance beams from these two rotameters are placed back
to back and connected by a cross beam, as shown in the above sketch. From this cross beam is suspended an arm whose position may be changed a t will by sliding it on the beam. This suspension arm is connected t o a Rotamatic air-operated control mechanism which in turn transmits air pressure to an air-operated valve in the flow line of the stream which is to be maintained at a fixed percentage of t h e main flow. I t can be seen t h a t t h e position of t h e arm suspended on the cross beam determines t h e control point or in other words, t h e flow ratio of one stream to the otherLiquid flows from 1GPM up to 6,000 G P M may be proportioned, and gas flows in equivalent volumes. The full and interesting details in regard to the new Rotamatic Ratio Controller are told in our bulletin 5Q-A which we will send t o you without any obligation. Owing to t h e paper shortage, please make your request upon your Company letterhead. Write t o F I S C H E R & P O R T E R COMPANY, 11U« County Line Road, Hatboro, Pa-
11111IIM V O L U M E
2 3,
NO.
14
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JULY
2 5,
1945
1281
