GB/T 39542.3-2020
Mechanical pencils for technical drawings—Part 3:Black leads—Bending strengths of HB leads

Standard No.

GB/T 39542.3-2020

Language

Chinese

Release Date

2020

Published By

General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China

Lastest

GB/T 39542.3-2020

Scope

This part of GB/T 39542 specifies the bending strength and test methods of black lead cores with a hardness grade of HB for technical drawing mechanical pencils.

GB/T 39542.3-2020 Referenced Document

• ISO 9177-2:1989 Mechanical pencils; part 2: black leads; classification and dimensions

GB/T 39542.3-2020 history

• 2020 GB/T 39542.3-2020 Mechanical pencils for technical drawings—Part 3:Black leads—Bending strengths of HB leads

GB/T 39542.3-2020 -All Parts