Bürkert Fluid Control Systems has launched the Type 8763 pressure controller, which has been designed specifically for accurate time-pressure dosing of micro quantities of fluid in the manufacture of pharmaceutical and medical diagnosis equipment.
Micro-dosing small quantities of fluid precisely and in large numbers presents several challenges that have been tackled using several techniques. Syringe dosing offers excellent precision for example, but it is not suitable for high-speed applications, it takes up quite a lot of space and cleaning of the equipment can be difficult.
Some improvements can be achieved through batch dosing – reducing the equipment footprint and increased speed, but flowrates can be limited, and dosing volumes may only have a certain amount of flexibility. There is also increased complexity in the control valves and dosing reservoir, all of which need to be cleaned between applications.
Bürkert offers a complete range of products that can be combined to create a perfectly matched dosing system, including the new Type 8763 pressure controller to maintain dosing accuracy.
The Type 8763 keeps the carrier gas at a constant pressure in the liquid reservoir regardless of the liquid level. As the liquid is dosed, the head height of the liquid in the reservoir drops, and without using the Type 8763, the pressure also reduces, causing the volume of the dispensed liquid to fall over a period of time. The pressure controller injects air, or another neutral carrier gas, into the reservoir to offset this fall in pressure, so the dosing accuracy is maintained.
This latest product offers millisecond response times and active pressure relief to maintain optimum performance and continuous dosing. This is made possible by the fast-acting, bi-directional pressure control valve which actively adjusts the pressure of the carrier gas, minimising the consumption of inert gas or compressed air.