The jet set: Nordson EFD improve process control with jet dispensing system

Nordson EFD says its jet dispensing system improves process control and reduces costs in medical product manufacturing through fluid deposit repeatability at high production speeds.  

With the ability to apply consistent shots as small as 2 nanoliters at speeds ranging from 150 Hz (cycles per second) up to an industry-leading continuous 500 Hz, the Pico system is ideal for high-speed, high volume applications that require many small, precise fluid deposits. The narrow design of the valves, with a width of approximately half an inch, makes them particularly well suited for installations where space is tight or valves need to be mounted close to each other.

Because the valve nozzle does not contact the substrate, the Pico system is also a good choice for applications where controlled amounts of fluid must be applied on surfaces that are not perfectly flat or  when contamination or damage may occur to fragile substrates through contact with the needle. In the case of medical electronics, with so many components tightly spaced on a small board or device, it is difficult to place the needle in many areas or get close to components.

By eliminating contact with the substrate, the Pico system solves this issue and also allows to eliminate the need for vertical Z-axis movement and precise height positioning, which can significantly increase production speeds.

The range of possible applications is huge. Sample uses include electronics (bonding cell phone speakers with UV-cure adhesives), life sciences (attaching needles to medical syringes), and precision mechanical applications (jetting small amounts of grease on micro gears).

Jet valve. The Pico jet valve contains two piezoelectric actuators composed of stacked ceramic coins that expand and contract in response to changes in voltage supplied through the valve driver.  

The extremely fast action of the piezoelectric actuators makes it possible to dispense fluid continuously at speeds of up to 150 cycles per second. Depending on the fluid being dispensed, the system can produce consistent shot volumes as small as 2 nanoliters, and the high resolution of the Pico valve controller (0.01 milliseconds) makes it possible to adjust deposit size with exceptional precision.

Pico valves are available in several different configurations to handle fluids with a wide range of viscosities. Nozzles are available with 150µm, 200µm, 300µm and 400µm orifice diameters to accommodate a wide range of dot sizes.

Most Pico valves, except those used exclusively for low-vicosity fluids, incorporate a heater near the fluid channel in order to thin the fluid to its optimum jetting viscosity. Depending on the rate of consumption, fluid can be supplied to Pico valves from syringe barrels, tanks or drum unloader systems.

Valve controller.  The Pico valve controller is available in 2- and 4-channel configurations. Both versions feature a graphical digital display and a user-friendly menu system   that makes it easy to set the fluid application parameters for each valve. Complex jetting processes can be easily created on a PC and downloaded via the integrated SD card slot. A password protection feature ensures that standard procedures are not changed accidentally, helping to achieve repeatable results.

The new generation of valves have a modular design and offer the flexibility to swap out only the parts that might be worn out while keeping the valve body in place.

Replacing just the worn out part instead of the entire valve saves both money and time. When only the faulty part of a valve needs replacing, it only takes minutes to change, rather than hours or days.