Problem: Products used in both the pharmaceutical and food industries must offer sterile design in order to prevent ingress of moisture and subsequent biological contamination. In some designs of valve actuators specifically, the interface between the valve actuator and the control head provides a pathway for the ingress of moisture onto the spring (or springs) of the actuator, resulting in corrosion, contamination from biological growth, and impairment of the correct functioning of the actuator itself. Solution: This problem has been solved by an innovation in valve actuator control on the Element valve units from Bürkert. Ian Webster, Bürkert’s hygienic processing field segment manager, said of the ELEMENT Type 8802 clean line range of diaphragm valves with integrated controllers: “Bürkert has changed not only its material of construction, to stainless steel, but also its design, and has evolved its valve range to make it more suitable for hygienic applications, including IP67 ingress protection.”
Valve actuator control is achieved by means of integrated pilot valves that can also be operated manually for easy local operation. For each operation, clean and dry control air is deliberately flushed into all areas of the actuator. This extends the valve’s reliability and life and ensures no impurities or moisture are drawn into the actuator.
Bürkert Fluid Control Systems