GB/T 17984-2010Twist drills -- Technical specifications (English PDF)

Foreword

This standard replaces GB/T 17984-2000 "Twist technical conditions." this standard and GB/T 17984-2000 compared to the main changes are as follows.

--- Modify the normative references, cancel the normative references cited in the standard year;

--- Revised 4.2 twist drill diameter working part taper down. To "0.02mm ~ 0.08mm" every length to 100mm "0.02mm ~ 0.12mm";

--- Revised 4.3, "its shank diameter tolerance f11" be replaced by "its shank diameter tolerance allowed for the f11";

--- Revised 4.5, "on the next adjacent basic dimensions twist length" with the words "on the basic scale within the next adjacent twist length Inch";

--- Modify the general level 4.9.1 twist groove indexing error in Figure 6;

--- Revised 4.11, twist drill core allowed increment "Allow" to "should";

--- Amend 4.12, increasing the general level of twist blade width of 9 and notes, and an increase in the formula in Appendix B. will Precision Twist Drill primary blade width of 9 to 10;

--- Revised 5.1, high speed steel does not set specific grade;

--- 5.3.2 revised working part hardness, 5.3.3 whole twist drill shank hardness, 5.3.4 taper flat tail, the original HV Increased hardness HRC hardness basis;

--- Added Appendix B, all the charts and formulas under all moved to Appendix B in the formula and unified index is a decimal Three significant number of points.

According to GB/T 17984-2000 "Twist technical conditions" amendments No. 1, to read as follows.

--- 5.3.2, "790HV ~ 900HV" to "780HV ~ 900HV";

--- Appendix A, Table A.1 No. 3, "the central contact against the cutting edge," to "close contact against the cutting corner Edge on. " the Standard Appendix A, Appendix B are informative appendices.

The standard proposed by China Machinery Industry Federation.

This standard tool by the National Standardization Technical Committee (SAC/TC91) centralized.

1 Scope

This standard specifies the general level of precision twist and twist size, material and hardness, appearance and surface roughness, marking and packaging Technical requirements.

This standard applies to press GB/T 6135.1 ~ 6135.4 and twist GB/T 1438.1 ~ 1438.4 with a variety of manufacturing process (rolling Molding process suitable for manufacturing precision twist), according to the agreement between, can also refer to the use of other twist. This standard does not apply to wood Workers drilling and homemade own twist.

2 Normative references

The following documents contain provisions which, through reference in this standard and become the standard terms. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to the agreement are based on research Whether the latest versions of these documents. For undated reference documents, the latest versions apply to this standard.

GB/T 1438.1 taper shank twist drills - Part 1. Morse taper shank twist types and dimensions GB/T 1438.2 taper shank twist drills - Part 2. Morse taper shank long series twist types and dimensions GB/T 1438.3 taper shank twist drills - Part 3. Morse taper shank twist drills lengthened types and dimensions GB/T 1438.4 taper shank twist drills - Part 4. Morse taper shank long twist types and dimensions GB/T 1443 used machine tools and tool shank taper from folder GB/T 1804 General tolerances Tolerances for linear and angular dimensions without individual tolerance GB/T 6135.1 straight shank twist drills - Part 1. coarse straight shank types and dimensions small twist GB/T 6135.2 straight shank twist drills - Part 2. Straight shank twist drill short and straight shank twist types and dimensions GB/T 6135.3 straight shank twist drills - Part 3. shank long twist drill types and dimensions GB/T 6135.4 straight shank twist drills - Part 4. Straight shank long twist drill types and dimensions

3 Symbol

d twist drill diameter Total length l l1 length of the channel Radial deltar working part of the shank axis runout deltak core drilling on the symmetry axis of the working part deltah oblique cutting edge runout of the working portion axis deltad trench indexing error Kmin minimum web thickness Recommended values \u200b\u200bof the land width fG Upper limit fU blade width of Lower limit fL width of the blade

4 Dimensions

4.1 twist drill diameter tolerance according to GB/T 6135.1 ~ 6135.4 and GB/T 1438.1 - 1438.4 of the regulations.