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SWEETENED CONDENSED Mit.K—CoNDENSING 
nulk, fitted with a valve. In the case of pans that have no 
special “striking” or sampling cup, this discharge is equipped 
with twor valves and a short nipple between valves, to make 
possible the sampling of the condensed milk while the pan is in 
operation. 
The Body or Vapor Belt represents the main part of the 
pan. It is cylindrical, of varying height and is equipped with 
copper coils which have their outlets either through the jacket 
or the walls of the body. Their upper ends connect, through 
the body of the pan, with the main steam line. Most pans are_ 
equipped with two to three or more coils located at different 
elevations: Since steam should be turned into the coils only when 
they are covered with the milk, it is desirable to have several 
short independent coils rather than but one large one. This 
will give a larger range of the quantity of milk that can be con- 
densed and increases the speed of evaporation. The coils vary 
in diameter from about three to six inches. ‘The upper and outer 
coils are the larger ones. The diameter and length of the coils 
necessarily vary with and are limited by the capacity of the pan. 
The shorter each individual coil, and the greater the number of 
independent coil sections and the greater the total heating sur- 
face, consistent with maximum rapidity of circulation of the 
mulk and with easy access to all parts of the jacket and coils, 
the better. Other things being equal, the more square feet of 
heating surface, the less steam pressure, by the gauge, is required 
to furnish the necessary heat for maximum evaporation. ‘This 
is important because high steam pressure in the jacket and coils 
means exposure of the milk to high temperature, which is un- 
desirable. The heating surface should be sufficient to make 
possible the complete condensation of the steam in the jacket 
and coils. If the heating surface is inadequate, more steam has 
to be turned into the jacket and coils, in order to secure the 
necessary heat for rapid evaporation, than will condense; free 
steam will blow through and out of the coils, resulting in un- 
economic and wasteful use of fuel, and jeopardizing the quality 
of the product. ‘The presence of numerous but short coils also 
increases the intensity of heat-transmission, as practically all 
of the steam is condensed in the uppermost convolution of each coil. 
There is a considerable variation in the area of the heating sur- 
