KNF expands its line of Smooth Flow Pumps

By integrating KNF Smooth Flow pump technology into the latest ink transfer systems, the number of components has been reduced, making new systems simpler, more flexible and more economical.

Drop-on-demand (DOD) digital inkjet technology continues to evolve and find new applications. Beyond simply printing graphic images on paper, the latest digital inkjet systems print colors and coatings on ceramics, glass, and textiles, and project functional fluids for 3D printing, printed electronics, and even biomedical and diagnostic applications.

Conventional recirculating DOD systems are complex and based on an intricate system of liquid pumps, air compressors, tanks and vacuum pumps. By integrating KNF Smooth Flow pump technology into the latest ink transfer systems, the number of components has been reduced, making new systems simpler, more flexible and more economical.

The diagram below shows that ink can be pumped directly from the recirculation tank (A) via a KNF Smooth Flow pump (B) through the degasser unit (C) and a filter (D), flowing smoothly through the printhead (E). Unused ink returns to the reservoir (A) via a second Smooth Flow pump (F). The meniscus vacuum is adjusted and maintained only by controlling the relative speeds of the feed and return pumps (B and F).

Reducing the number and complexity of components makes the system smaller, simpler, and less expensive to produce, operate, and maintain. With ink flowing unimpeded through the system, a lower operating pressure is achieved, reducing the load on the pumps and other system components and prolonging the life of the system.

Another benefit of low pulsation is that the system runs smoothly and quietly and is more energy efficient and more reliable. Reducing the total volume of ink in the system makes purging, cleaning, and priming faster and less costly.

With a wide range of flowpath material options, KNF diaphragm pumps offer excellent compatibility with even the most difficult ink chemistry and abrasive particles. Diaphragm pumps handle pigmented inks more gently than other positive displacement pump technologies (i.e., peristaltic, gear, and piston). Thanks to Smooth Flow technology, KNF diaphragm pumps are even gentler and ideal for recirculating very sensitive or abrasive particles in functional inks. 

KNF Smooth Flow liquid pumps offer flow rates from 15 mL/min – 12.4 L/min. Their low pulsation minimizes friction in pipes, prevents bubble formation, and eliminates the need for external dampers. This gentle, low-shear conveyance of media protects fragile system components and sensitive media from potential damage, while producing very low vibration and noise. Other features include precise control and easy integration, reliable self-priming, run-dry safety, long service life, and appropriate IP ratings. Flow path material options are also available to maximize compatibility.