FORCING AND FORCING STRUCTURES 



69 



| inch is considered the minimum size. Table II, below, shows 

 the radiating surface the various sizes of main supply pipes, or 

 risers, will furnish with steam or hot water. 



TABLE II. CAPACITY OF MAIN SUPPLY PIPES, OR RISERS 



Size of Pipes 

 (in inches) 



'1 



2 



Radiating Surfaces supplied 

 (in square feet) 



155 



225 

 40O 

 620 

 QOO 



1220 

 1600 



TABLE III. DIMENSIONS OF STANDARD WROUGHT-!RON PIPE 



Wrought-iron welded pipe (for steam and water}. Pipes i inch and below 

 are butt-welded and proved to 300 pounds per square inch, hydraulic pressure. 



Pipes i^ inch and above are lap-welded and proved to 500 pounds per 

 square inch, hydraulic pressure. 



The preceding table gives the standard sizes and principal di- 

 mensions of wrought-iron pipe. From this the amount of pipe 

 required for a given radiating surface can readily be computed. 

 , To determine radiating surface, i . Find the radiating surface by 

 dividing the area of glass in square feet by the results in Table I. 

 Hot-water pipes can be kept at a temperature of 1 80 F. if desired. 



