FAW Engine Aseembly-SCR Box Assembly

SCR Catalytic Muffler: The heart of the system. This integrated unit houses the catalyst substrate where Diesel Exhaust Fluid (DEF) chemically converts NOx into harmless nitrogen and water vapor, while also functioning as part of the exhaust silencing system.

SCR Tank Assembly: Stores and supplies the Diesel Exhaust Fluid (DEF), typically incorporating level sensors, temperature management, and a supply pump.

Urea Nozzle: Precisely injects atomized DEF spray into the hot exhaust stream upstream of the catalyst, ensuring optimal vaporization and mixing for efficient chemical reaction.

Temperature Sensor: Monitors exhaust gas temperature upstream of the catalyst. Precise temperature data is vital for the ECU to control DEF injection timing and dosage – the reaction only occurs effectively within a specific temperature window.

Nitrogen Oxygen Sensor (NOx Sensor): Positioned downstream of the catalyst, this advanced sensor measures the concentration of residual NOx in the treated exhaust. It provides real-time feedback to the engine control unit (ECU) for closed-loop control of DEF dosing accuracy and system diagnostics.

Nitrogen and Oxygen Sensor Protection Frame: A robust metal shield safeguarding the sensitive Nitrogen Oxygen Sensor from physical damage, road debris, and excessive heat, ensuring long-term sensor reliability in harsh operating environments.

Hexagon Socket Head Cap Screws: High-strength fasteners used throughout the assembly. These provide secure, vibration-resistant clamping for mounting the SCR Catalytic Muffler to the exhaust manifold/downpipe, attaching sensor brackets, securing the Urea Nozzle housing, and fixing the Protection Frame. Their socket head design is ideal for confined spaces typical in engine installations.