DRYIT Semi-Continuous Tray Drier
Practical Action
Introduction
This manual is designed primarily to aid the construction of the Practical Action Semi-
continuous Tray Drier.
The machine is described in detail and its construction outlined.
This manual compliments the engineering drawings TD001 to TD102, which are essential if
a drier is to be made.
The manual does not cover the heat source and ducting required for a complete drier, but
this is discussed briefly.
The drier consists of a cabinet containing a stack of 15 trays, which hold the material to be
dried. The cabinet is mounted on a base and has a lifting mechanism, (to lower/ lift the
trays). This mechanism is mounted on a frame over the drying cabinet.
Semi-continuous operation is achieved by the use of the lifting mechanism. The mechanism
allows a tray of dried product to be removed and replaced by one with fresh material, without
interruption of the drying process. The drier is made from mild steel angle, plywood, steel
plate and bar, and a small amount of hardwood for bearings. The trays are made of
hardwood with nylon mesh bases and mild steel angle rein-forcers.
In this manual the drier has been divided into seven main areas. These are:
1.) The base
2.) The upper frame
3.) The drying cabinet
4.) The lifting mechanism
5.) The trays
6.) The cladding
7.) The drying cabinet doors
Areas 1 to 4 are shown in the exploded diagram, figure 1.
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