Precision Manufacturing Process & Quality Control Of PTC Needles

https://admin1.seo.com.cn/CustomerAdmin/S_News/Create?ru=%2FCustomerAdmin%2FS_News%2F

Though seemingly simple, a Chiba needle's performance hinges on tight-tolerance tubing, refined tip grinding, and rigorous QC.

1. Raw Material

Medical-grade SUS304/SUS316L capillary tube (ASTM A269/A908) or Nitinol (ASTM F2063)

Incoming checks: spectroscopy, hardness (HV 180–220 SUS304), OD ±0.02 mm, ID ±0.01 mm, surface flaw inspection

2. Cutting & Straightening

Diamond cut to length; deburr

Multi-roll straightening → straightness ≤0.3 mm over full length

3. Lumen Conditioning

Plug-drawing / die-pulling to final ID/OD

Electropolishing interior:​ Reduces Ra <0.2 µm → minimizes cell sticking & clot blockage

4. Tip Grinding - Critical Step

CNC bevel grinding to 25°–30° long bevel using resin-bond diamond wheel

Tip thickness ≤5 µm; penetration force <0.5 N (phantom gel)

Optional secondary relief grind to lower drag & improve US tip echo

Ultrasonic wash to remove micro-debris (prevents particulate embolization)

5. Exterior Finish & Marking

Electropolish outer surface

Laser-etched depth marks (5/10 mm) ±0.1 mm tolerance

Optional "echogenic ring" (micro-groove or inert coating) near tip

6. Hub Assembly & Sterilization

PP/PC hub press-fit or solvent-bonded to tail

Assemble stylet (if included), protective sleeve

Wash → ISO Class 7 cleanroom packaging → Tyvek pouch → EO sterilization (AE ≥12) → quarantine for sterility / EO residue / endotoxin

Key QC Tests

Common defects from poor manufacturing: dull tips → high insertion force & tearing; rough lumen → clogged aspirate / hemolysis; inaccurate markings → depth misjudgment.