Water quantity meter: KEBABLEND / M
A well-known manufacturer in the field of garden accessories came to us with a tricky task: we were to develop a plastic water flow meter that measures consumption using the simplest and most robust method possible. No sooner said than done. Our application engineers set to work on the task with some headaches, but full of zeal and all their know-how. Our solution: function integration with an injection-molded magnet that simultaneously functions as a turbine and signal generator for speed measurement. We proved that something like this is actually possible with a prototype ready for series production. The result: an ingeniously simple flow meter that costs little and lasts a long time.
The challenge of this task was a tough one: We had to find an alternative for an axially mounted magnetic impeller and develop a one-piece solution with partially magnetic areas. The elimination of conventional magnets usually leads to cost savings and a longer service life of the component. Furthermore, the material must also function properly in contact with water and exhibit sufficient sliding and wear behavior.
On this basis, we developed a turbine-shaped component made of KEBABLEND / M with three blades for optimum volume flow. The tests with the first prototypes showed that the interaction of the reed contact as a sensor and the turbine wheel as a signal generator worked excellently, and the molded-on axle bearing led to a simple and efficient solution.
The material is a magnetic compound with a high ferritic content. It can be used to produce injection-molded magnets as plastic components. In this case, the material is based on polyamide 12. Depending on the application, PA6, PPS or PPA can also be used as the carrier polymer. Depending on the additives (hard ferrites, soft ferrites or rare earths), we can realize magnetic properties tailored to the component application. For example, remanence or coercivity play a major role.
The advantage over sintered magnets is, among other things, the enormous freedom of design, the good toughness & strength and the great cost-saving potential. By eliminating the need for conventional magnets and the associated assembly costs, the material offers optimum functional integration, not only in the area of speed measurement.
Magnetization takes place during the manufacturing process in the mold of the injection molding machine, ensuring efficient series production without extended cycle times (in-mold magnetizing). In this process, the component is magnetically aligned while it is still in a plastic state. This is because the magnetic properties of the component are enhanced by means of anisotropic particles.
Today, the water meter is successfully in use. What started with an idea has become reality thanks to the know-how of BARLOG Plastics. Some time before, we had the opportunity to prove our abilities as problem solvers in this field. Together with the manufacturer of premium garden accessories, we optimized a product from the range of irrigation systems.
Here, we substituted a steel spring and created a corrosion-free solution made of KEBABLEND / M. Thus, we succeeded in producing a magnetic switching mechanism as a travel limiter for the sprinkler head.
You too can benefit from BARLOG Plastics’ innovative materials and knowledge of plastics processing. Rely on excellent service in all aspects of plastics technology from a single source and receive an individual solution tailored to your needs.