The QB3 is one of Proportion-Air’s flagship electro-pneumatic pressure regulators. It is a perfect choice for applications that require higher flow ranges or positive pressure through vacuum. The unit features two solenoid valves, closed loop electronic controls, pressure transducer, and is mounted onto an internal volume booster. The analog monitor signal output is used to compare against the command signal to automatically adjust on the fly. The QB3 can deliver excellent repeatability and accuracy up to ±0.25-0.50% of full scale. The device is packaged in a rugged aluminum enclosure to protect it against typical industrial environmental conditions. It can be also mounted in any orientation (must be vertical for pressures lower than 10 psi).

Application Examples

Vacuum through positive pressure leak testing: The QB3 has been used in a multi-step I.V. bag leak test application. First, the bag is inflated with nitrogen to the appropriate pressure level. Once it has been confirmed there are no leaks, the QB3 uses a vacuum source to remove and exhaust the excess nitrogen. The bag is then ready to be filled with the required fluid.

High pressure catheter extrusion: A QB3 pressure regulator unit can be used to assist in the forming of a catheter. In this example, a GX unit is used for the initial pressure control of the inner diameter (I.D.) of the catheter as it exits the extruder. The QB3 then provides vacuum pressure control to form the outer diameter (O.D.) of the catheter as it enters the cooling chamber. The catheter is then fully sized and ready to be trimmed with a cutter.