QB/T 1024-2018
活动铅笔用黑铅芯
Black leads for mechanical pencils
2018-07-04
GB/T 39542.3-2025
技术制图活动铅笔 第3部分：黑铅芯 HB铅芯弯曲强度
Mechanical pencils for technical drawings—Part 3:Black leads—Bending strengths of HB leads
2025-05-30
GB/T 39024-2020
木杆铅笔黑铅芯 分类和直径
Black leads for wood-cased pencils—Classification and diameters
2020-07-21
GB/T 39542.2-2025
技术制图活动铅笔 第2部分：黑铅芯 分类和尺寸
Mechanical pencils for technical drawings—Part 2:Black leads—Classification and dimensions
2025-05-30
GB/T 43550.2-2023
一般用途活动铅笔和铅芯 分类、尺寸、质量和试验方法 第2部分：黑铅芯
Mechanical pencils and leads for general use—Classification, dimensions, quality and test methods—Part 2: Black leads
2023-12-28
GB/T 43550.1-2023
一般用途活动铅笔和铅芯 分类、尺寸、质量和试验方法 第1部分：活动铅笔
Mechanical pencils and leads for general use—Classification, dimensions, quality and test methods—Part 1: Mechanical pencils
2023-12-28