FOREST SERVICE WATER SPRAY DRY KILN. 
41 
extra screens should be provided in order that a clean screen may be 
slipped in when a dirty screen is taken out. The dirty screens may 
be cleaned by washing with a hose on the reverse side. The frames 
Warer Supply to Sprays 
Fig. 13.— Pump connections for simplified humidity control for use in kilns where only one drying schedule 
will be used. (See page 40.) 
J* and jambs should be built of cypress and fastened together with 
brass screws. The burlap should be attached to frames with sepa- 
rate strips held in place by screws. 
GUTTER. 
The gutter at the bottom of the spray chamber should have a 
pitch to the drain of at least 1 inch in 8 feet, and should be not less 
than 3 inches deep at the shallow end. It should connect with the 
drain pipe through a cast iron wash rack without trap. 
DRAIN PIPE. 
Wherever practical, drain piping should be cast iron soil pipe with 
% ^ regular oakum and lead calked joints, graded to the return well with 
a pitch of 1 inch in 10 feet. 
The drain pipe should have a by-pass to the sewer for flushing out 
debris in piping before starting kilns. For less expensive installa- 
tion sewer tile can be used. 
