Bürkert Fluid Control Systems has recently launched its latest addition to the micro fluidics range, the Type 6712 WhisperValve, which is a plunger type design with media separation, that measures only 7mm wide and has a switching time of less than 5 milliseconds. Designed for medical applications such as dialysis, drug delivery systems and in vitro diagnostic work as well as precision inkjet printing, this latest development from Bürkert also has a very low switch noise of less than 36dB, a mere whisper.
The new valve raises the bar in terms of miniature valve design by combining a host of features that make it particularly well suited to micro dosing applications in the medical sector as well as others requiring compact, precision valves with excellent media separation characteristics.
Designed with a minimal internal volume of just 5µl the WhisperValve has excellent flushability and can be specified with sealing materials that offer high levels of chemical resistance.
Medical equipment such as dialysis machines and drug delivery systems are very often in close proximity to the patient and may be required to operate day and night so near silent operation is a major benefit that minimises any disturbance of the patient. In addition, the internal design of the valve delivers an excellent cleaning cycle which guarantees the removal of one fluid before the next process begins.
Work within the in vitro diagnostics (IVD) sector helps to detect diseases or infections by using a controlled flow of reagents to determine a diagnosis. Automated equipment relies on built-in cleaning systems to flush the critical paths with cleansing solution between each sample. The combined attributes of the Type 6712 WhisperValve make it an ideal component for IVD machines.
Of course, reliability and efficiency are key components of the design, with a life cycle in excess of 30 million switching cycles, under laboratory conditions, and excellent media separation which ensures no contact between the actuator and the medium. The actual service life achieved will depend on the type of medium, temperature, pressure, seal material and the specific operational conditions of the application that the valve is used in.
Power comes from either a 12 or 24 VDC supply and consumption is just 0.9W, which is very efficient considering the speed of actuation and the near silent operation.
The response time for this valve is fast, which combined with the low internal volume and small orifices, provides a very accurate micro-dosing capability. With output pressure measured at 1 bar and an ambient temperature of 20°C according to DIN ISO 12238:2001 the response time is just 1ms (with a pressure build-up 0-10%) and 5ms with a pressure drop of 100-90%.
