BS ISO 3438:2013 pdf free
BS ISO 3438:2013 pdf free.Subland twist drills for holes prior to tapping screw threads
This International Standard specifies the dimensions of subland twist drills with Morse taper shanks and cylindrical shanks for holes prior to tapping screw threads.
The drills are designed to produce holes prior to tapping metric threads (coarse pitch series) over a selected range of:
一M8 to M30 for subland twist drills with Morse taper shanks;
一M3 to M14 for subland twist drills with cylindrical shanks.
This International Standard complements ISO 2306.
The relationship between the symbols of this International Standard and those according to the ISO 13399 series is given for information in Annex A.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 296, Machine tools一Self-holding tapers for tool shanks
ISO 2768-1, General tolerances 一Part 1: Tolerances for linear and angular dimensions without individual tolerance indications
ISO 10899:1996, High-speed steel two-flute twist drills一Technical specifications
3.1 General
All dimensions and tolerances are given in millimetres. Tolerances not specified shall be of tolerance class“c” in accordance with ISO 2768-1.
3.2 Subland twist drills with Morse taper shank
The dimensions for subland twist drills with Morse taper shanks shall be in accordance with the dimensions shown in Figure 1 and given in Table 1.
3.3 Subland twist drill with cylindrical shank
The dimensions for subland twist drills with cylindrical shanks shall be in accordance with the dimensions shown in Figure 2 and given in Table 2.
This third edition cancels and replaces the second edition (ISO 3438:2003), of which it constitutes a minor revision with the following changes:
一merging of ISO 3438:2003 and ISO 3439:2003 into a single standard;
一adding of an informative annex giving the relationship between the symbols of this document and the symbols according to the ISO 13399 series.BS ISO 3438 pdf download.
