A 3D-printed cooling nozzle to prevent grinding fire. After years of preliminary work, Innogrind has managed to develop one. The so-called Innozl™ is now sold all over the world.
Jos van Langh, owner of Innogrind, has been researching grinding fire: overheating due to excessive grinding for years. Grinding fire causes irreparable damage to the product to be ground.
During various consultancy analyses, he found out that a deficient coolant supply was (and is) often the cause of grinding fire at many companies. For example, the coolant is added from too far away from the contact point or does not reach the right place at the right speed. This is why he developed the Innozl™; a cooling nozzle that is matched to the particular grinding process and applies the coolant much more precisely in the contact zone, the place where the tool and material meet.
3D printing
3D printing ultimately turned out to be the most ideal production technology and titanium the best material. Initial tests showed that plastic was not strong enough; it could not withstand the high pressures created when spraying coolants. So it became metal. Because the wall thickness had to be 0.3 to 0.5 mm thick, Innogrind eventually turned to 3D printing. "By applying 3D printing, we were not hampered in the design possibilities. You can make natural shapes so that the coolant does not experience obstruction from internal sharp corners. This allows us to tailor the cooling nozzle exactly to the customer's production process."
The product looks simple, but according to Van Langh, there is a unique design behind it. "At first glance, you see a nozzle with a few tubes but these tubes are internally provided with a certain structure that can only be applied with 3D printing. This ensures that the coolant does not come out in a fixed jet but in a laminar jet consisting of lots of small droplets. The surface tension of the coolant is reduced by the design, making cooling much better."
Partner
In AAE, Innogrind found a knowledge partner that contributed to the design and production. This resulted in an optimal printing process of newly designed cooling nozzles. The 3D printing technique used by AAE is called Selective Laser Melting. In it, a thin layer of metal powder is melted together using a laser. Parts are thus built up layer by layer, making it possible to create highly complex (internal) geometries and free forms that can only be realised with 3D printing. As the powder is melted, metal parts made of, for example, stainless steel 316L or titanium are given the strength required for the cooling nozzle.
The Innozl™ cooling nozzle is mainly supplied to machine manufacturers and large end users in the metalworking industry. Due to the higher costs of 3D printing, the cooling nozzle is above traditional cooling nozzles in terms of price level, but this has not been a problem for any customer so far. Van Langh: "We have heard that the return on investment is less than two months. This is because the Innozl™ allows the user to produce more without grinding burn, while requiring about 30 to 60 per cent less coolant. All in all, it provides a more stable grinding process and people are happy to pay a bit more for that."
By: Kelly Bakker
Photo: Innogrind
