Fisher R3622X00012 Nozzle Flapper Assembly

Technical Specifications

Model：R3622X00012 Brand：Fisher Product Type: 3622 series pneumatic positioner nozzle flapper assembly

Module Feature

Fisher R3622X00012 is precision nozzle flapper sensing assembly for Fisher 3622 force balance pneumatic valve positioner. It converts mechanical movement of feedback lever into tiny pneumatic pressure change, which is sent to pneumatic relay for air amplification. High precision machined nozzle and metal flapper, stable performance under cyclic working conditions. Widely used in oil,gas,chemical and power plant globe control valve pneumatic loop maintenance.

Working principle: Change nozzle back-pressure by adjusting gap between flapper and nozzle, generate pneumatic signal for relay amplification Onboard components: Precision nozzle, metal flapper, feedback spring, mounting bracket, sealing gaskets

LED indicators

Not equipped

Hardware self-diagnosis

Visual inspection, nozzle blockage check, flapper deformation inspection, zero/span calibration test, air pressure signal test after assembly

Programming software

No dedicated software required

Pneumatic Parameters

Supply air:20~150psi clean dry instrument air Signal type:Variable back pressure from nozzle-flapper gap

Mechanical & Structure

Mounting:Installed inside Fisher 3622 pneumatic positioner housing Protection class:IP66

Environmental

Operating temperature:-40℃ ~ +85℃ Ambient humidity:5~95% non-condensing Certification:CE Status:Fisher 3622 positioner spare assembly

System compatibility

Dedicated for Fisher 3622 pneumatic valve positioner, matched with 657/658 diaphragm actuators and globe control valves.

Function

R3622X00012 is core sensing assembly manufactured by Fisher. The gap variation between flapper and nozzle creates back pressure change, which becomes the control signal input to pneumatic relay. It converts valve stem travel into pneumatic signal to realize closed loop positioning. Dirt blockage, flapper bending or spring fatigue will cause positioning drift, oscillation and calibration failure. It is key spare part for 3622 positioner overhaul.

Installation

Follow lockout/tagout safety procedure before installation. Cut off instrument air supply and release residual pressure. Disassemble 3622 positioner housing, replace old nozzle flapper assembly. Adjust flapper gap and feedback spring tension. Reassemble positioner, run zero/span calibration and air tightness test, verify valve stroke performance.

Interface

Pneumatic signal port connected to pneumatic relay, mechanical linkage connected to positioner feedback lever, no LED indicators on R3622X00012.

Diagnostic

Valve oscillation: Dirty nozzle or flapper deformation. Calibration impossible: Feedback spring fatigue or incorrect gap. Poor positioning accuracy: Nozzle blocked by dust. Unstable back pressure: Gasket leakage inside assembly.

Product Brief

R3622X00012 Fisher 3622 pneumatic positioner nozzle flapper assembly,converts mechanical stroke into pneumatic signal for relay amplification,for industrial 3622 positioner maintenance and overhaul,precision sensing spare part.