Dongfeng Renault engine parts Common rail return oil pipe assembly 1104152-E9300

Engineered to facilitate smooth, unrestricted return of excess fuel from the common rail to the tank, the pipe features a mandrel-bent construction that creates a continuous, smooth internal pathway. This design minimizes flow resistance (pressure drop ≤ 0.2 bar at maximum return flow rate of 5 L/min), ensuring excess fuel from the injectors and rail is efficiently recirculated—critical for maintaining stable common rail pressure (up to 2,000 bar for high-pressure side). Unlike crush-bent pipes with flattened sections that restrict flow, this optimized design prevents pressure buildup in the return circuit, which can cause injector misfueling or common rail valve damage. The pipe’s diameter is calibrated to match Dongfeng Renault’s engine fuel flow requirements, ensuring no backpressure that could reduce fuel efficiency or increase emissions

To prevent fuel leaks (a safety hazard and cause of fuel waste), the assembly integrates dual-seal connector technology. Each threaded connector features a precision-machined conical seat (60° angle) that mates with the fuel rail’s sealing surface, creating a metal-to-metal seal that resists vibration-induced loosening. Additionally, each connector is fitted with a nitrile rubber (NBR) O-ring (Shore A hardness 70) that provides a secondary seal against minor surface irregularities, ensuring zero leakage even under engine vibration. The quick-connect fitting for the fuel tank uses a push-to-lock design with a built-in O-ring that creates an airtight seal, eliminating the need for hose clamps. Unlike traditional rubber hoses that crack or loosen over time, this sealed connection system ensures leak-free operation for 80,000+ km

Built to withstand the harsh environment of Dongfeng Renault’s engine bay (exposure to fuel, oil, coolant, and high temperatures), the pipe assembly uses rugged materials. The pipe itself is made of seamless aluminum alloy (6061-T6) with a 0.8mm wall thickness—lightweight yet resistant to corrosion from diesel fuel additives and road salt. The aluminum surface is coated with a ceramic-based heat-resistant layer ( temperatures up to 180°C), protecting the pipe from heat radiated by the engine block or exhaust manifold. The connectors are made of 304 stainless steel with zinc-nickel plating (8μm thickness) that passes 1,000 hours of salt spray testing without rust, ensuring easy disassembly during maintenance. Unlike carbon steel pipes that corrode within 2–3 years, this material combination extends the assembly’s service life to 5+ years

Engineered for efficient replacement in repair shops, the assembly simplifies installation with user-friendly features. It comes with pre-marked alignment tags that match reference points on the engine, guiding technicians to route the pipe correctly without interference. The threaded connectors are pre-coated with anti-seize compound (compatible with diesel fuel) to prevent thread galling and ensure easy removal during future maintenance. Installation takes 25–30 minutes using standard hand tools—no specialized bending or cutting required. To guarantee quality, each unit is manufactured in an IATF 16949 certified facility and undergoes strict testing: pressure leakage testing (10 bar for 5 minutes), flow rate verification, corrosion resistance trials, and vibration testing (200,000 cycles at 10–2,000 Hz). Backed by a 24-month warranty against manufacturing defects (e.g., pipe cracking, seal failure, or connector corrosion), it provides Dongfeng Renault engine owners with reliable fuel return performance and long-term peace of mind