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  • CCST

CCST question

Approximately what is the pressure, in psig, on the bottom of a 10-ft, flat bottom, open tank filled to 100 percent of capacity with a fluid that has a specific gravity of 1.1?
 
A. 2.50
B. 4.76
C. 9.50
D. 25.4
 

CCST Answer

The correct answer is B, 4.76 psig. A column of water exerts a pressure on the bottom of the tank according to the formula below. The level at 100 percent will be 10 feet.
 
Therefore,
 
PSI = [height in feet × SG] / 2.31 feet/psi
 
       = [10 feet x 1.1] / 2.31
 
       = 4.76 psi
 

Reference: Goettsche, L. D. (Editor), Maintenance of Instruments and Systems, Second Edition, ISA, 2005. 

 

 

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