The venous cannula hub body is the connector block that joins a venous drainage cannula to the cardiopulmonary bypass circuit tubing. It carries the barb, the luer lock port and the clamp interface, and it must hold vacuum without leaking while remaining smooth enough to limit haemolysis and protein deposition at the flow path. Buyers report leaks at the barb root and rough internal surfaces on machined-from-solid hubs. Ningbo Ruican casts the hub body with a cored flow passage, machines the sealing features and barb after heat treatment, and electropolishes the wetted path to Ra 0.4 um for a cleanable, low-turbulence surface.
Specifications
| Parameter | Specification |
|---|---|
| Casting process | Silica sol lost wax investment casting with soluble or ceramic core for the flow passage |
| Material options | AISI 316L, 17-4PH (H900 / H1025), AISI 420 |
| Dimensional tolerance (ISO 8062-3 CT grade) | CT5 as cast; CT4 on barb, luer port and sealing faces after machining |
| Machining | CNC turning of the barb and luer taper, 4-axis milling of the clamp flats, drilling of the side port |
| Surface finish (Ra) | Ra 0.4 um electropolished on wetted flow path; Ra 1.6 um machined externally |
| Weight range | 25 g to 150 g per hub depending on tubing size and port count |
| Typical lead time | Tooling 4-5 weeks; first article 2-3 weeks after tooling; production 5-7 weeks |
Key features
- Cored internal flow passage removes the deep drilling operation, cutting cycle time and eliminating the tool witness marks that trap protein in solid-machined hubs.
- Electropolished wetted path at Ra 0.4 um reduces flow turbulence and gives a surface that cleans and inspects consistently between production lots.
- Luer taper and barb are machined after heat treatment to gauge, holding the sealing geometry that prevents the leaks reported at the barb root.
- Uniform wall section through the hub transition avoids sink and porosity in the thick barb-to-body junction, confirmed by X-ray sampling.
- 316L chemistry controlled to ASTM A743 CF3M equivalents with low carbon for weld repair and corrosion resistance in saline contact.
- 100% visual and dimensional check on sealing features, plus pressure or vacuum leak testing to the customer’s method on request.
- Optional laser marked size, lot code and flow direction applied after passivation for traceability in the perfusion set.
Applications
- Venous drainage cannula hubs for cardiopulmonary bypass circuits.
- Arterial return cannula connectors and aortic root vent adapters.
- Cardioplegia delivery line hubs and pressure monitoring manifolds.
- Extracorporeal membrane oxygenation circuit connectors.
- Perfusion tubing set manifolds and recirculation line blocks.
- Autotransfusion and cell salvage reservoir inlet bodies.
Quality & compliance
Ningbo Ruican is not an ISO 13485 contract manufacturer. It supplies cast and CNC-machined components in 17-4PH (H900/H1025), AISI 420 and AISI 316L together with project-level documentation under the customer’s Quality Agreement, including material traceability and ISO 10993-5 biocompatibility test support. For perfusion hardware we add chemistry certification, ferrite and surface condition records, and leak test evidence gathered to the method the customer specifies, with any deviation reported and dispositioned through the customer’s non-conformance process.
FAQ
Can you guarantee a leak free barb and luer interface?
We machine both features after heat treatment, verify with calibrated gauges, and leak test to the method and acceptance criteria in your drawing or Quality Agreement. Sample size and test pressure follow your specification, and results are reported with the lot documentation.
Why cast the flow passage instead of drilling it?
Casting the passage removes a deep drilling step, avoids tool marks and burrs at the internal junction, and lets us keep wall thickness uniform at the barb root. The cored surface is then electropolished to Ra 0.4 um, producing a smoother wetted path than drilling alone can achieve.
Which material do you recommend for blood contact?
AISI 316L is the usual choice for blood-contacting hub bodies because of its corrosion resistance and low carbon content. Where higher strength is needed at the clamp interface, 17-4PH H900 is available, with the same surface finish and passivation route applied.
Do you perform the biological evaluation?
No. Ningbo Ruican supports the customer’s biological evaluation by supplying material certification, surface finish data and test coupons for ISO 10993-5 cytotoxicity testing to the protocol you specify. The device-level biological evaluation report remains the responsibility of the device manufacturer.
How is cleanliness controlled before packing?
Parts are washed, passivated per ASTM A967, rinsed in deionized water and dried, then packed to the customer’s specification. Where a cleanroom pack is required, we can apply the packing and labelling instructions you provide and document the process on the traveller.
What volumes do you support for perfusion sets?
We support prototype quantities through to annual volumes in the tens of thousands, using multi-cavity tooling where volume justifies it. Tooling is maintained and stored for repeat orders, and we can hold agreed safety stock to smooth your release schedule.
CTA
Send your venous cannula hub drawing, 3D model or sample for a DFM review, surface finish recommendation and quotation. Contact Wendy She — sales@cnsandcasting.com — WhatsApp +86-13777124360, or visit https://cnsandcasting.com to discuss your perfusion hardware program with Ningbo Ruican.
