Two Part Dispensing (2K)
There are several options for the application of two part materials in industrial applications that give considerable benefits over manual mixing.
These systems ensures that the mixing ratio is correct, that the mixing process is complete and that air inclusions are minimised. In these processes the two components are supplied in the correct ratio without air inclusion and are only mixed as they pass through disposable plastic mixing tubes attached to the system outlet. The materials can be supplied in two part cartridges which contain the materials in the required ratio or through meter mix dispense (MMD) systems which output the two materials in the required ratio. While the cartridge systems offers simplicity and lower capital cost the MMD systems allows faster through put and savings through reduced material costs although there are higher capital cost.
In between these two options is the PAM system which utilises a dispenser with reservoirs that are refillable from bulk containers.
There are accurate precision units for specialised applications and spraying and dispense units for two part paints and coatings.
For multi part mixing including powders as well as liquids, planetry centrifugal mixers are used.
Meter Mix Machines can dispense directly from material reservoirs or bulk supply containers and can operate at high speeds and pressures. For these reasons the static mixers used are MS or ME types and are made to withstand higher pressures. Also they are normally fitted with metal shrouds which fit over the outside diameter of the mixer, this prevents the outer tube expanding under pressure and allowing some material to pass through the gap that is created. They also address OHAS concerns.
When mixing of the two materials is very difficult dynamic mixers can be used. In these systems the spiral flute has a tongue on it and the dispensing head connects to it and spins the flute at high speed
Piston Machines utilise two cylinders whose diameters match the desired ratio and hence are fixed ratio machines. A pneumatic system moves the two pistons to load and then empty the material giving an adjustable but discreet shot size.
Geared Pump Machines have two geared pumps that are driven by pneumatic or electric motors with the relative speed of the two pumps setting the ratio. Within limits these machines are variable ratio and give continuous flow.
Precision Mixers use two positive displacement pumps driven by variable speed drives allowing variable ratio and either controlled shot size or flow rates.