Novo Nordisk A/S
Method of producing needle cannula with reduced end portion by electrochemical etching

Abstract:

A needle cannula (100) and a method for producing a needle cannula comprising providing a needle cannula tube (10) with an end portion (30). The end portion (30) comprises an outer surface, and a given type of steel comprising carbon (C) in 0.07 to 0.15% by mass, silicon (Si) in 0.50 to 1.00% by mass, manganese (Mn) in 5.0 to 7.5% by mass, phosphorus (P) in 0 to 0.030% by mass, sulfur (S) in less than or equal to 0.015% by mass, chromium (Cr) in 17.5 to 19.5% by mass, nickel (Ni) in 6.5 to 8.5% by mass, and nitrogen (N) in 0.20 to 0.30% by mass. The method further comprises establishing an electrochemical reaction to remove material from the outer surface of the end portion (30), and thereby providing a needle cannula (100) with a tapered end portion.