Instrument Manufacturing and Repair Questions and Answers Flashcards

What type of stainless steel is most commonly used in the manufacturing of surgical instruments?

Answer: Type 420 martensitic stainless steel

Type 420 martensitic stainless steel is most commonly used because it can be hardened through heat treatment, providing edge retention and spring properties.

What is the passivation process in surgical instrument manufacturing?

Answer: Creating a protective chromium oxide layer through chemical treatment

Passivation is a chemical treatment using nitric or citric acid that removes free iron and promotes a protective chromium oxide layer, enhancing corrosion resistance.

What is the purpose of tungsten carbide inserts in needle holders and scissors?

Answer: To provide superior hardness and wear resistance at the working surface

Tungsten carbide inserts provide exceptional hardness (approximately twice that of stainless steel) and wear resistance, extending the working life of needle holder jaws and scissor cutting edges.

When should an instrument be retired from service rather than repaired?

Answer: When repair costs approach replacement value or structural integrity is irreversibly compromised

Instruments should be retired when repair costs approach replacement cost, or when structural integrity cannot be adequately restored.

What is the forging process in surgical instrument manufacturing?

Answer: Shaping heated steel blanks under high pressure using dies

Forging involves heating steel blanks and shaping them under extreme pressure in precision dies, producing instruments with superior grain structure and durability.

What is the purpose of instrument lubrication (instrument milk) during reprocessing?

Answer: To protect moving parts, prevent corrosion, and ensure smooth mechanical function

Instrument milk protects moving parts from corrosion, reduces friction-related wear, and ensures smooth operation. It is applied after cleaning and before sterilization.