Dongfeng LoongGine Engine parts Sealing ring 1008036-E9300

As a critical barrier against fluid and gas leakage, this sealing ring’s core function is to prevent leakage of engine oil, coolant, and exhaust gas between mating components (e.g., cylinder head cover and cylinder block, oil pan and crankcase). It operates based on the elastic compression sealing principle:

When the mating components are fastened (via bolts with specified torque), the sealing ring is compressed to 20%-30% of its original cross-sectional height.

The ring’s elastic material deforms to fill tiny irregularities on the mating surfaces (e.g., micro-scratches or machining marks), forming a continuous, pressure-tight seal.

For dynamic sealing scenarios (e.g., water pump shafts), the ring’s material also maintains flexibility to accommodate slight component movement, preventing leakage caused by vibration or thermal expansion.

This sealing effect protects the engine from oil loss (which causes lubrication failure) and coolant leakage (which leads to overheating), while also blocking exhaust gas ingress into the crankcase (which contaminates engine oil)

To withstand harsh engine operating environments, the sealing ring uses high-performance elastomeric material with targeted resistance properties:

Base Material: Made of nitrile rubber (NBR) with fluorine modification (FKM blend)—a material chosen for its balanced performance in oil resistance, temperature tolerance, and durability. NBR’s polar structure provides excellent resistance to mineral-based engine oil and diesel fuel, while the fluorine additive enhances resistance to high temperatures and chemical corrosion (e.g., from coolant additives).

Key Material Properties: The material has a Shore hardness of 70±5, ensuring sufficient elasticity for compression sealing and rigidity to maintain shape under pressure. It exhibits a volume change of ≤15% after 72-hour immersion in standard engine oil (API CK-4) at 120℃—far below the industry limit of 25%—preventing swelling-induced seal failure.

Temperature Resistance: Maintains stable sealing performance across a wide temperature range of -40℃ to 150℃, covering extreme cold (winter startup in frigid regions) and high-temperature conditions (engine operation under full load, where oil temperatures can reach 130℃)

The sealing ring features optimized structural design and strict manufacturing controls to ensure consistent sealing performance:

Cross-Sectional Design: Adopts a standard O-ring cross-section (circular) for most static sealing applications, as this shape provides uniform compression and maximum contact area with mating surfaces. For dynamic applications (e.g., water pump), it may include a lip-shaped cross-section to enhance friction resistance and prevent premature wear.

Dimensional Precision: Manufactured via injection molding with CNC-controlled tooling, ensuring dimensional tolerance of ±0.05mm for inner/outer diameter and ±0.03mm for cross-sectional thickness. This precision guarantees a tight fit in the component’s sealing groove, avoiding "extrusion damage" (where excess material is forced into gaps under pressure).

Surface Finish: The ring’s surface undergoes a deburring and polishing process, resulting in a smooth finish (Ra ≤ 0.8 μm) that reduces friction in dynamic applications and prevents material tearing during installation

The sealing ring is widely applied in Dongfeng LoongGine engine components across various vehicle types, including:

Static Sealing Applications: Cylinder head cover (sealing engine oil), oil pan (preventing oil leakage), intake manifold (sealing air-fuel mixture), and coolant pump housing (blocking coolant leakage).

Dynamic Sealing Applications: Water pump shaft (sealing coolant while accommodating shaft rotation) and crankshaft front/rear oil seals (preventing oil leakage from the crankcase).

In terms of installation, it offers significant advantages:

Easy Installation: The flexible rubber material allows easy insertion into sealing grooves, and no special tools are required—installation can be completed by hand or with basic tweezers during engine maintenance.

Compatibility with Standard Torque: Works with the original engine’s recommended bolt torque (e.g., 25-30 N·m for cylinder head cover bolts), requiring no adjustment to fastening procedures.

Cost-Effective Maintenance: As a low-cost but critical component, regular replacement of the sealing ring (during engine overhauls or component repairs) prevents expensive damage caused by fluid leakage (e.g., engine overheating from coolant loss, bearing failure from oil shortage). A single ring can last 60,000-80,000 km under normal operating conditions