This standard specifies the type and size of long twist drills with Morse taper shank. This standard applies to Morse taper shank long twist drills with a diameter of 5.00 mm to 50.00 mm.
GB/T 1438.2-1996 history
2008GB/T 1438.2-2008 Taper shank twist drills.Part2:The types and dimensions for long Morse taper shank twist drills
1996GB/T 1438.2-1996 Taper shank twist drills--Part 2: The types and dimensions for long Morse taper shank twist twist drills