Ningbo Ruican manufactures investment cast turbocharger bearing housings — also referred to as centre housings — for turbo OEMs, rebuilders, and aftermarket suppliers serving passenger car, commercial vehicle and marine engine platforms. High-SiMo ductile iron resists thermal cycling and oxidation up to approximately 800 °C, while the silica sol lost wax process reproduces cored water jackets and the flanged gas inlet as a single near-net-shape component. Finish machining of the bearing bores, thrust faces and flange datum is completed in-house on CNC equipment, so every housing ships mating-ready for rotor assembly.
Key Features
- Precision-machined bearing bores — CNC boring and honing-ready bores hold roundness and coaxiality across the full journal length for stable rotor dynamics.
- Integrally cored cooling jacket — complex ceramic cores produce enclosed water passages with no welds or brazed inserts, reducing leak paths.
- Flanged gas inlet with machined datum face — cast integrally and finish-milled to accept the turbine housing clamp and gasket sealing surface.
- High-SiMo metallurgy for thermal fatigue resistance — silicon-molybdenum ductile iron maintains strength and scale resistance through repeated heat soak cycles.
- Pressure-tight casting integrity — controlled solidification plus optional dye penetrant and pressure decay testing to support coolant circuit sealing requirements.
- Consistent machinability across batches — verified matrix structure keeps carbide content and hardness within a defined window to protect tool life.
Materials & Heat Treatment
| Material | Standard | Condition | Application note |
|---|---|---|---|
| High-SiMo ductile iron | EN 1563 EN-GJS-SiMo45-6 / equivalent GGG-SiMo 4.5 | Ferritic-pearlitic, annealed or as-cast per drawing | Default grade for bearing housings exposed to sustained exhaust-side heat soak |
| High-SiMo ductile iron with Mo 1.0 | Customer specification variants | Annealed for machinability | Higher creep and thermal fatigue resistance for heavy-duty commercial vehicle turbos |
| Heat-resistant stainless steel | ASTM A297 HF / HK equivalents | Solution annealed | Selected where exhaust gas temperatures exceed ductile iron service limits |
| Heat-resistant stainless steel | ASTM A297 HH / 1.4837 | Solution annealed | Elevated temperature strength and oxidation resistance in high-performance turbocharger platforms |
| All variants | Customer / national standard equivalents | Verified by EN 10204 3.1 | Chemistry and tensile verification supplied with each production heat lot |
Specifications
| Parameter | Value |
|---|---|
| Casting process | Silica sol investment casting (lost wax); water glass route offered for lower-tolerance, cost-driven part families |
| Casting weight range | 0.3 kg – 15.0 kg per piece (typical turbo bearing housing 0.6 – 4.5 kg) |
| Dimensional tolerance | ISO 8062 CT4-CT6 (silica sol process); CT7-CT8 available via water glass route |
| Minimum wall thickness | 3.0 mm nominal for structural walls, thinner locally with engineering review |
| As-cast surface roughness | Ra 6.3 – 12.5 µm, improved to Ra 3.2 µm on machined sealing faces |
| Machining capability | CNC horizontal and vertical machining centres, CNC turning; bore tolerance to IT7, typical ±0.01 mm on bearing bore diameter and coaxiality to 0.02 mm |
| Inspection and testing | CMM dimensional layout, roughness measurement, hardness mapping, dye penetrant, hydrostatic or pneumatic leak test where specified |
| Pressure rating | Coolant and oil circuit proof testing per customer specification |
| MOQ | 300 pieces per part number for new tooling; prototype and validation runs negotiable |
| Tooling lead time | 20-30 days for wax die, core tooling and first article samples |
| Production lead time | 35-50 days after sample approval, depending on volume and machining content |
Applications
- Passenger car and light commercial vehicle turbocharger centre housings
- Heavy-duty truck and bus engine turbochargers with high heat soak duty cycles
- Variable geometry turbocharger (VGT) bearing housings
- Marine and genset engine turbocharger assemblies
- Turbocharger remanufacturing and performance aftermarket programmes
Quality & Documentation
Ningbo Ruican operates an IATF 16949 certified quality management system, and turbocharger bearing housing programmes run under automotive process discipline: controlled melting practice, defined gating and feeding simulation, statistical capability studies on critical characteristics, and full heat-lot traceability from charge material through to packed part.
Process selection — silica sol vs. water glass. Silica sol investment casting is recommended for turbocharger bearing housings because the integrally cored cooling jacket, thin oil gallery walls and flange profile demand CT4-CT6 accuracy and clean internal cores. Water glass casting is offered for simpler bearing housing families and larger parts where tolerance is less demanding and the priority is unit cost reduction. Process route is confirmed with the customer at quotation stage against drawing tolerance, annual volume and total cost targets.
Documentation supplied:
– EN 10204 3.1 material certificates including chemical analysis, mechanical properties, matrix structure and nodularity verification for ductile iron
– First Article Inspection (FAI) dimensional reports against ballooned drawings, with CMM data for all drawing-numbered characteristics
– PPAP-style documentation packages (process flow diagram, control plan, PFMEA, MSA results, initial process capability studies) supplied under the customer’s Quality Agreement and PPAP submission level requirement
– Non-destructive testing records: dye penetrant, ultrasonic where specified, and hydrostatic or pneumatic coolant circuit test results
– Heat-treatment charts and microstructure photomicrographs retained per batch
Why Ningbo Ruican
- 17 years of casting experience supplying turbocharger, automotive and industrial components to export customers worldwide.
- One-stop casting plus CNC machining in a single facility, protecting bore concentricity and datum integrity while shortening lead time and removing split-vendor risk.
- OEM and ODM programmes from drawings or samples, covering tooling design, casting simulation, prototyping, validation lots and series production.
- IATF 16949 certified quality system, delivering documented process control, full traceability and repeatable series delivery performance.
Request a Quote
Send your drawings to Wendy She — sales@cnsandcasting.com | WhatsApp +86-13777124360
