Rushan Dongsheng Alloy Co., Ltd. (东晟合金) is an authentic OEM & Aftermarket source factory in Shandong, China. Providing ±0.003mm tolerance valve guides and high-temperature sintered valve seat inserts for 1,200+ global engine models.
Rushan Dongsheng Alloy Co., Ltd. is a dedicated Chinese manufacturing enterprise with extensive metallurgy and CNC machining capabilities. We specialize in producing OEM-grade automotive engine valve guides and sintered valve seat inserts for commercial trucks, passenger vehicles, construction machinery, and marine diesel applications.
Full PPAP Level 3 documentation, Certificate of Conformance (CoC), and global ocean customs clearance supported.
Precision engineered to form the ultimate thermal dissipation and sealing pair inside the engine cylinder head.
Ensures precise valve stem centering and smooth axial reciprocation under severe heat. Internal bores are diamond micro-reamed to Ra 0.2-0.4μm with internal spiral oil retention grooves to eliminate stem scuffing.
Forms the combustion chamber gas-tight compression seal. Sintered with high-cobalt and high-chromium superalloys to endure continuous 850°C - 950°C exhaust gas hammering without micro-cracking or seat recession.
Inspect micro-geometry, diamond-reamed bore tolerances, internal spiral oil reservoirs, 3-angle valve seat bevels, and cryogenic press-fit limits.
Internal diameter precision bore calibrated using multi-spindle diamond micro-reamers. Ensures hydrodynamic oil wedge stability and zero micro-scuffing under 7,000+ RPM reciprocating valve cycles.
Precision ground OD for worn cylinder head bore restoration. Calibrated press-fit interference maintained.
Search by Engine Model, Brand, or OEM Number. Custom manufacturing from client samples & 2D/3D technical drawings welcomed.
Engineered specifically for continuous 850°C - 950°C exhaust gas environments, extreme combustion pressure, and zero scuffing.
High-density Fe-Cu-Co-Mo alloy matrices with embedded solid graphite lubricants. Offers exceptional hot hardness (HRC 38-48), zero microcracking, and superior self-lubricating wear resistance.
Preferred for heavy-duty commercial and racing engines. Exceptional thermal conductivity rapidly channels valve head heat into the cylinder head cooling jackets, eliminating stem seizure.
Classic OEM-grade formulation with fine lamellar pearlite and network phosphide eutectic. Outstanding damping, oil film retention, and economical high-volume production reliability.
Engineered for severe turbo-diesel and CNG/LPG alternative fuel engines. Resists dry combustion micro-welding, acid condensation corrosion, and high-frequency valve hammering.
| Material Grade | Applicable Component | Hardness Index | Max Operating Temp | Fuel Compatibility | Key Engineering Advantage |
|---|---|---|---|---|---|
| DS-PM40 (Fe-Cu-Mo-C) | Valve Seat (Intake/Exhaust) | HRC 38 - 45 | 800°C | Gasoline / Diesel Engines | High wear resistance, cost-efficient mass production |
| DS-STELLITE (Cobalt-Chrome Alloy) | Heavy Diesel Exhaust Seat | HRC 42 - 50 | 950°C | Turbo Diesel / CNG / Heavy Fuel | Zero recession under severe dry combustion, acid resistant |
| DS-BRONZE (CuSn8P) | Commercial Vehicle Valve Guide | HRB 88 - 98 | 450°C | Heavy Truck Common Rail / Racing | Superb heat extraction, eliminates valve stem seizure |
| DS-CAST IRON (Cr-Mo-P) | Passenger / Truck Valve Guide | HB 210 - 260 | 400°C | Gasoline / Light Diesel Engines | Excellent oil film retention, smooth damping & noise suppression |
Every batch is verified with air-gauge bore sorting, spectral chemical analysis, and Zeiss CMM 3D GD&T testing.
Multi-channel pneumatic micrometer inspects 100% of valve guide internal diameters and taper within ±0.002mm limits.
Direct-reading spectrometer analyzes exact percentages of Fe, Cu, Co, Mo, Cr, and P elements before sintering or pouring.
Sub-micron precision verification of valve seat angles, concentricity, roundness, and cylinder head press-fit tapers.
Optical microscope checks pearlite fineness, carbide distribution, and sintered pore density for every furnace lot.
Ensuring 100% zero-oxidation, zero-distortion delivery from Qingdao Port / Weihai Port to global client warehouses worldwide.
All ground precision surfaces coated with de-watering protective oil and sealed inside multi-layer VCI vapor corrosion inhibitor bags. Guaranteed 24-month rust-free shelf life across tropical ocean freight routes.
Supported options: Neutral reinforced kraft boxes for aftermarket parts wholesalers, vacuum blister trays for robotic automated assembly, and custom client-branded OEM color boxes with barcoding.
Standard export plywood pallets compliant with ISPM-15 IPPC guidelines (zero quarantine delay at EU/US/Middle East ports). Strapped with PET heavy-duty bands, corner angle boards, and waterproof stretch wrap.
Direct container trucking to Qingdao Port (2.5 hrs) and Weihai Port (1 hr). Complete customs export documentation provided: Bill of Lading, Certificate of Origin (CO / Form E / Form F), Commercial Invoice, and Packing List.
Send us your required engine models, OEM part numbers, or technical drawings for an immediate factory-direct quote.
Direct factory answers regarding Minimum Order Quantities (MOQ), metallurgical test reports, lead times, custom CAD tooling, and ocean shipping.