New micro-valve from Bürkert for medical technology

In the 21st century, the requirements for fluid control systems in medical technologies as in other areas have changed significantly. The goal is to minimise: minimise liquid consumption, minimise the size, minimise the dosing and wash cycles, and above all, minimise the distance to the application. With the aim of meeting these requirements, Bürkert has developed a new micro-valve.

With a width of 7mm and a height of 26mm, the Type 6712 'WhisperValve' fits in miniature apparatus. The 7mm width makes it ideal for 9mm titre plates, says the company, but it can also be installed in smaller spaces. For applications on dispensing arms, pipetting arms and dosing robots the low overall weight of the valve is an advantage.

The power consumption of the WhisperValve is also low: in both switching and holding it uses less than 1W, which eliminates the need for power reducing electronics.

The new actuator is designed to operate at a sound level below 36dB. The typical metal-to-metal contact noise of a solenoid valve is eliminated in the WhisperValve.

Typical examples of lab applications in which the valve can be used are the analysis of blood or urine. The flushing properties of the valve are achieved by a minimal internal volume, including the valve flange, of 5µl. The accumulation of air bubbles, a frequent problem in smaller valves due to poor flushability, has been effectively minimised by Bürkert in the new valve. With a pressure differential of 1 bar, the longest dwell time of a fluid is 5ms.

In addition to high dosing precision, the requirement for exact flow rates is also increasing in diagnostics and other applications. For manufacturers of fluid control components, that means increasing the power density of the actuators, so that smaller valves can also switch high pressures. The pressure working range of the Type 6712 is 3 bar during switching and 8 bar during the flushing process of the open valve.