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I. DOOR SYSTEMS
The dryer utilizes one (1) style of doors, which is Pneumatic Automatic Doors.
1. Pneumatic Automatic Description/Operation
a. Description
The Pneumatic Automatic Doors run on a single aluminum track mounted above the doors and a split
track mounted on the bottom of the doors. The doors are held on the track by four (4) stainless steel
wheel assemblies; two (2) are located on the top of the doors and two (2) are located on the bottom of
the doors. Additionally, in the center portion on the top of the doors there is a magnet used in conjunction
with proximity sensors, which are mounted above the doors.
b. Operation
There are two (2) 1” bore x 18-3/8” stroke cable cylinders attached to the top of the doors to pneumatically
open and close the doors. When air is applied into the outside ports of these cable cylinders the doors
will open. If air is applied into the inside ports of these cable cylinders the doors will close. On each of
the four (4) ports is a flow control valve used for adjusting the opening and closing speeds of the doors.
These flow controls only vary the speed in the exhaust direction. Air to the cable cylinders is supplied
through a 4-way valve. When 24 VAC is applied to the valve, the doors open...if no power is applied, the
doors close. A 3-way valve is used to supply air to the 4-way valve.
If the “EMERGENCY STOP” (E-Stop) is engaged, the air is automatically exhausted so that the doors
can be opened manually.
1) In a 2 door application, there are two (2) additional cable cylinders, a 4-way valve added for the
operation of the rear doors.