Cummins engine spare parts Exhaust valve C5669131 in stocked

As a critical component exposed to high-temperature exhaust gases, this valve is crafted from Inconel 751 nickel-based superalloy, boasting exceptional thermal stability. It maintains mechanical strength (tensile strength ≥900MPa) at continuous operating temperatures up to 850℃, with short-term tolerance of 1000℃—ideal for X15 engines producing exhaust gas temperatures (EGT) of 750-800℃ under full load. The alloy’s high chromium content (20%) forms a dense oxide layer on the surface, preventing oxidation and corrosion from exhaust by-products (e.g., sulfur oxides). This material ensures the valve resists thermal fatigue and warping, extending service life to ≥300,000km in heavy-duty operations

Engineered to maintain tight sealing in the combustion chamber, the exhaust valve undergoes ultra-precision machining. The valve head’s sealing face is ground to a surface roughness of Ra ≤0.2μm and a flatness of ≤0.01mm, ensuring leak-tight contact with the valve seat (leakage rate ≤0.5L/min at 1MPa pressure). The valve stem is polished to Ra ≤0.1μm, reducing friction with the valve guide by 25% and minimizing wear. A hardened tip (HRC 58-62) on the stem end ensures reliable contact with the valve lifter, preventing premature wear. This precision maintains the engine’s compression ratio (18:1) and combustion efficiency, reducing fuel consumption by 3-4% and NOx emissions by 15%

Optimized to resist wear and corrosion from aggressive exhaust gases, the valve integrates multiple protective features. The valve head and stem are coated with a 0.1mm-thick stellite alloy overlay (Co-Cr-W) via plasma spray, enhancing wear resistance by 60% compared to uncoated valves. The stem is treated with nitriding (case depth 0.3-0.5mm), improving surface hardness to HV 800 and preventing scuffing against the valve guide. The valve undergoes a 500-hour cyclic oxidation test (850℃) with no significant material loss, ensuring durability in engines burning low-quality diesel fuel with high sulfur content. These features prevent valve recession and seat wear, reducing maintenance frequency

The exhaust valve is designed for efficient installation and long-term cost savings. Its precision-machined stem and head ensure quick alignment with the valve guide and seat, reducing installation time by 40%—a technician can replace a set of 6 valves in 4 hours. The valve’s compatibility with Cummins’ original valve springs (OE 5255596) and retainers eliminates the need for aftermarket adjustments. By maintaining combustion chamber sealing, it prevents expensive issues like valve leakage (which causes power loss) and cylinder head damage (repair costs up to $8,000). Backed by a 2-year/250,000km warranty, it reduces unplanned downtime for fleet operators and avoids repeated replacement costs of low-quality valves