Polaroid produce instant films at their Dumbarton factory. In the past they have bought in developer in 44 gallon drums from a sister company. One drum of developer will produce a produce with a single film speed. When one of these drums is opened, it instantly has a limited shelf life, and a large batch of film has to be produced.
Polaroid developed a process to address this issue. From a two part mixture they can generate a range of film speeds. Pan Controls designed a three pump mixing system to address this problem. Two of the pumps adjust the ratio of the component parts, and the third one acts as a metering pump to ensure a very accurate dispensation for each film pod.
The operator has a simple keypad and display arrangement which allows the film speed parameters to be entered and converted to the correct pump velocities.
The new 3-pump system has allowed Polaroid to produce relatively short runs of special products economically, and to keep stock levels down.