Model (scale 1:4) of wool drying machine by John & William McNaught

Model (scale 1:4) of wool drying machine by John & William McNaught, Rochdale, Manchester, England, the original having been made around 1914.

This model represents part of a machine, usually consisting of seven compartments, which dries the wool, previously washed, by volumes of dry warm air which are passed continuously through the wool. The wet washed wool is fed on to the travelling feed apron of the machine from the washing machine, and enters the first compartment through pair of rollers and is carried forward over a specially shaped plate or bridge by an upward current of air set in motion by a fan which runs at 1,350 revolutions per minute and heated by steam in a tubular heater. The damp air passes out of the compartment through a perforated plate at the top. Short fibre, small particles of dirt, and fine kemps, blown through the perforations, collect on the upper surface of the plate and are removed by hand. From the last three or four compartments the hot air, which now contains little moisture, is collected and taken back into the fan chamber. The temperature in the compartments can be varied to suit different kinds of wool by means of a slide valve which regulates the amount of air admitted. Drying is effected in from it to 31 minutes, and the output of the machine is about 400 lb. per hour.