The QFF3 three-valve manifold is an integrated instrument manifold specifically designed for use with differential pressure transmitters, integrating two isolation valves (high pressure and low pressure) and one equalizing valve into one compact body. This manifold typically features female threaded connections (e.g., NPT 1/2” or M20×1.5). Through precision internal flow path design, it enables connection or isolation between the transmitter‘s high/low pressure chambers and the impulse lines, as well as equalization between the two chambers. This manifold is primarily used for differential pressure transmitter root isolation, online zero calibration, equalizing operations, and system venting. Its core purpose is to achieve safe isolation of differential pressure, flow, or level measurement systems and online transmitter maintenance without interrupting process operation, thereby ensuring continuous, stable operation and measurement accuracy of automated control systems.

1. Integrated compact design: Integrates two isolation valves and one equalizing valve into one body, reducing leakage points and simplifying installation.

2. Female thread connections for easy installation: Standard female threads on both ends ensure convenient connection and reliable sealing.

3. Standardized operation for transmitter protection: Sequential operation of the three valves enables safe commissioning, zero calibration, and online isolation, preventing single overpressure damage.

4. Metal-to-metal hard seal for reliability: Tapered or spherical hard seal between disc and seat ensures wear resistance and long cycle life.

5. All-stainless steel construction: Body and internal components made of high-quality stainless steel (304/316) for excellent corrosion resistance in various industrial media.

6. High pressure capability and wide temperature range: Nominal pressure up to PN16-PN40, temperature range from -70℃ to 570℃, suitable for medium to high pressure and complex applications.

Structure Diagram of QFF3 Three-Valve Manifold

Component name and material

Performance Specification Sheet

QFF3 Three-Valve Manifold Outline Drawing

Outline dimension table