74 SWEETENED CONDENSED M1LK—CoNDENSING 
heating surface and is operated properly, the drip ends of the 
jacket and coils should discharge warm water only, and not free 
steam. The jacket and coils should he free at the drip or dis- 
charge ends so that all condensation water may be quickly and 
continuously removed. ‘This is necessary in order to make the 
most economical use of the steam and to secure high efficiency 
of evaporation. In order to guard against back pressure the 
drips may be equipped with suitable check valves. 
Fig. 20. Steam coils in Rogers pan 
Courtesy of C. BE. Rogers 
Through the walls of the body of the pan also enters the 
milk draw pipe. ‘This pipe connects with the hot well and through 
it the milk rushes into the pan. Immediately outside of the 
pan the milk pipe should be equipped with a valve to regulate 
the inflow. ‘The size of the milk draw pipe and valve is governed 
by the capacity of the pan; usually two to three inches in di- 
ameter. Inside of the pan the milk pipe should be turned down. 
[f this provision is not made, the milk shoots straight across the 
