This Part specifies the types and dimensions of the following high-speed steel turning blades: ——Circular cross section (see Chapter 2); ——Square cross section (Chapter 3); ——Rectangular cross section (Chapter 4); —— Trapezoidal Sections (Chapter 5).
GB/T 4211.1-2004 history
2004GB/T 4211.1-2004 High speed steel tool bits Part 1:Types and dimensions