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Why syringe glide force is set by the tool
Glide force is a clinical property that comes from the barrel and plunger fit, which means it is fixed before the first part is moulded.
Glide force is what a clinician feels, and it comes from the clearance between barrel and plunger together with the surface finish of both. Neither of those can be adjusted by changing process parameters after the tool exists.
That makes glide force a tooling specification rather than a process one. It has to be stated as a target at the design stage, along with the acceptable range, and verified on moulded samples rather than calculated from drawings.
The same logic applies to luer taper fit. Two tapers have to agree within hundredths of a millimetre for a connection to seal without locking, and both are set in steel long before any process engineer sees the part.
Specifications
| Set by | Barrel and plunger clearance and surface finish |
|---|---|
| Fixed at | Tool design, not process adjustment |
| Verified on | Moulded samples, not drawings |
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