4066B000 — Non-Return Valve 2 inch Repair & Overhaul

Component Overview

A two-inch non-return valve is a check valve that permits airflow in one direction within the pneumatic and air management ducting while preventing reverse flow, protecting upstream sources and preventing backflow between bleed or cross-bleed manifolds. It typically uses a spring-loaded flapper or poppet that opens under forward pressure and seats closed when flow reverses. Because it operates passively in a high-temperature, pulsating air stream, its principal degradation modes are seat and seal erosion, spring fatigue or breakage, flapper hinge wear, sticking, and reverse leakage past a worn seat. Inspection commonly reveals leakage in the closed direction, sluggish opening, and worn or chattering elements. Overhaul restores the seat, flapper, hinge, and spring to ensure free forward flow and tight, reliable reverse sealing.

Aircraft Application

Part number 4066B000 (Non-Return Valve 2 inch) is installed on the Dornier 328. QTC supports operators and MROs servicing this platform with certified repair and overhaul.

Our Repair Capability

QTC repairs and overhauls 4066B000 to the original manufacturer's specifications under our FAA and EASA Part 145 approvals. Our team — including former OEM pneumatic & air management engineers — performs teardown, inspection, cleaning, component replacement, functional testing, and certification, returning a serviceable unit with the appropriate airworthiness release. We also develop repairs for rejected and beyond-economic-repair (BER) hardware.

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Frequently Asked Questions