This is the gear-housing body that encloses the precision gear train of a volumetric infusion pump, syringe pump or ambulatory drug-delivery device. It is investment cast in AISI 316L stainless steel for exceptional corrosion resistance to glutaraldehyde, isopropyl-alcohol, hydrogen-peroxide vapour and other healthcare cleaning chemistries that would attack plastic or coated aluminium housings. Investment casting reproduces the multiple internal bearing seats, the precision sensor-pocket, the motor-flange boss and the seal-grooves as a single high-stiffness part — so the gear train sees minimum deflection under load, and pump-flow accuracy stays within ± 2 % even after a million motor pulses. After casting the housing is CNC machined on both faces and on all bearing seats, then passivated and electropolished. This part is external to the patient fluid path for the typical use case — it sits inside the chassis; for wetted-path versions, additional surface treatment and weld-sealing is recommended.
Material Specifications
- Standard: AISI 316L (UNS S31603 / EN 1.4404 / ASTM A276 Type 316L)
- Heat-treat condition: Annealed / solution-quenched (~ 200 HB)
- Composition reference: ASTM A276; EN 10204 3.1 chemistry certificate
- Bio-compatibility screening: ISO 10993-5 cytotoxicity report available on request
- Surface electropolished: Ra ≤ 0.4 µm standard for medical chassis surfaces
- Magnetic: Non-magnetic in the annealed condition
Dimensional Capability & Tolerance
- Weight range: 80 g – 1.2 kg
- Min. wall thickness: 1.5 mm (bearing seats ≥ 2.5 mm)
- As-cast linear tolerance: ISO 8062 CT5 (≈ ±0.10 mm / 25 mm); CT6 for non-critical walls
- CNC post-machining: ±0.03 mm on bearing-bore axes; bore-to-bore positional ≤ 0.04 mm
- Bearing bore roughness: Ra 0.4 – 0.8 µm (clean bearing fit)
- Surface flatness: ≤ 0.02 mm on flange faces (gasket integrity)
- Inspection: 100% CMM first-article; in-process gauging per lot; FAIR / ISIR per lot
Surface Finish Options
- CNC finished + passivated: Ra 0.8 µm standard
- Electropolishing: Ra ≤ 0.4 µm (recommended for medical chassis)
- Hard anodising or polymer-coating: optional for decorative / labelling zones
- Laser-etched logo + serial: optional, in-line
- Custom packaging: cleanroom bagged or double-bagged per OEM specification
Applications
- Volumetric infusion pumps (hospital / clinic)
- Syringe pumps for ICU and paediatrics
- Ambulatory infusion pumps for chemotherapy / pain management
- Medical drug-delivery devices and wearable injectors
- Dialysis machine gear housings
- Medical laboratory automation equipment
Why Choose Ningbo Ruican for This Part
- 17+ years of stainless-steel precision investment casting with 0.5 % typical lot-to-lot chemistry drift — important for long-running OEM pump programmes
- Single-piece leak-tight chassis: investment casting replaces aluminium-billet machining + welding + sealing; fewer fasteners, fewer leak paths
- In-house CMM metrology: Zeiss Contura verified every lot; bearing-seat geometry traced for life-of-program repeatability
- Documentation for FDA / EU MDR submissions: FAIR / ISIR, REACH / RoHS, biocompatibility screening provided per project
Certifications & Regulatory Positioning
- IATF 16949 (valid)
- EN 10204 3.1 chemistry and mechanical certificates — supplied per lot
- FAIR / ISIR per lot, full raw-material lot traceability (mill heat → casting → heat-treatment lot → finished part)
- REACH / RoHS compliance statement per lot
- Project-level ISO 13485 documentation packages supplied on request; Ningbo Ruican is not an ISO 13485 contract manufacturer — we work as the casting + CNC supplier under your Quality Agreement.
