Reliable mixing and dosing
With our DM 50x series equipment portfolio, we offer automation solutions for the mixing and dosing of 2-component reactive materials – especially polyurethanes, silicones and epoxy systems.
For this, the material components have to be prepared, i. e. stirred in the tank and loaded with air, and then conveyed to the mixing head. In the mixing head, the components are then mixed dynamically and the liquid sealant system is dosed in precise quantities.
Each of the process steps involved has its own specific requirements, which show how good a machine actually is. Our experience acquired over decades of machine development makes the difference and ensures the reliability of our machines.
Material preparation begins with stirring
Depending on the material system, it may be necessary to load the A component with air, for example in order to obtain a fine-cell foam, or – just the opposite – to degas it for bubble-free clear potting. The agitator therefore has the function of not only counteracting sedimentation, but also of ensuring uniform air loading or degassing and temperature distribution. For an optimal degassing process there is also the option of thin-layer degassing. This takes place in the material pressure tanks.
Recirculation for a constant flow of materials
No matter how precise a pump is: It is a real challenge to achieve accurate dosing – especially in the case of long hose routes – if the material always comes to a standstill after dosing and has to be set in motion again for the next dosing step.
An exact application rate is particularly difficult to achieve when small quantities are to be dosed and the valve opening times are correspondingly short. For this reason we keep the material flowing at a consistent rate with our recirculation principle and keep the pressure in the system at a constant level as a result.
This is ensured by the precision gear pumps installed in the dosing machine cabinet.
Dynamic mixing systems for high requirements
However, many industrial applications require highly complex material systems that exceed the capabilities of static mixers. Dynamic mixing systems are required here in order to reliably process these difficult recipes for industrial production.
With the mixing heads for dynamic mixing, liquid to highly viscous polymer reaction materials can be processed. Depending on the mixing head, discharge rates from 0.05 to 100 g/s are possible. The mixing ratio is continuously adjustable from 100:1 to 1:100.
We offer you various mixing head designs, from the simple MK 20 with static mixing to our dynamic models from the MK 400 series.
They are used for our low-pressure mixing and dosing systems for the application of sealing foams, adhesives and casting compounds based on polyurethane or silicone.
Dynamic mixing makes the difference
The greatest possible level of material homogeneity after mixing 2-component material systems with different viscosities – even in the case of demanding, asymmetrical mixing ratios – can only be achieved with dynamic mixing. This is performed by our MK 800 mixing heads .
Static mixers are capable of swirling material components of similar viscosity during continuous dosing. These can be used for material systems that allow generous deviations in the mixing ratio and react comparatively slowly, thereby preventing material that has already stuck together in the mixing tube from collecting and forming a blockage.
Accurate refilling for a continuous supply of material
When used in fully automated manufacturing processes, automatic refilling stations ensure material-specific preparation, homogeneous consistency and a continuous supply of materials to the component containers of the mixing and dosing system – without exposure or contamination of the products to be filled. Partially equipped with an automatic lifting device for more operating convenience and greater occupational and system safety. Production interruptions are therefore a thing of the past.
Optional Equipment used to increase process and dosing accuracy
Additional equipment options can be ordered for the DM 50x dosing machine series which further increase the process and dosing accuracy, e. g.:
- Sensor for spare part recognition
- Pneumatic AIR-CLEAN nozzle cleaning
- NOZZLE-CONTROL nozzle measurement unit
- WEIGHT-CONTROL dosing weight control
- High pressure water flushing of the mixing chamber
