When you’re looking for the complete data and dimensions on inch-based machine screws, the standard you’ll want to use is ASME B18.6.3. Now there’s a new 2013 Edition that has just been released for this document. It’s titled “Machine Screws, Tapping Screws, and Metallic Drive Screws (Inch Series)” and the 2013 update is available from Document Center.
You may remember it under the old number, ANSI/ASME B18.6.3. This dual designation is the way that ASME used to let users of the standard know that a publication was adopted as an American National Standard. Now ASME keeps all the glory of the standard for itself in the numbering system and just lets you know in the cover sheet material that the standard is ANSI adopted.
Certainly, I have often wondered how all those nuts, bolts, and screws in the hardware store are numbered and categorized. The ASME standards really provide the basis for the uniformity of the products that are used throughout the industry.
Regarding the content of the standard, as the title suggests slotted and recessed head machine screws, tapping screws, and metallic drive screws are all covered. There are also appendices for:
- the protrusion gaging of flat countersunk head screws,
- across-corners gaging of hex head screws,
- penetration gaging and wobble gaging of recessed head screws,
- approximate hole size for tapping screws,
- wrench openings for hex and square products,
- thread dimensions for the No. 0000, No. 000, and No. 00 sizes,
- means for determining effective grip lengths on screws,
- documentation for screw types and head types relegated to not-recommended or limited usage status, and
- formulas on which dimensional data are based.
This is a lengthy standard — a 140 pages in all. It is a revision of the ASME B18.6.3 2010 Edition, which is now obsolete.
So whether you’re looking to procure or produce machine screws, remember that the ASME B18.6.3 is the standard to meet. You can purchase all current and many obsolete ASME standards from Document Center Inc. Go to our web store, www.document-center.com, and search for the document you want by number or by title information (keyword). Or if you prefer, contact us by phone (650-591-7600), fax (650-591-7617) or email (info@document-center.com). We’re here to assist you with your standards collection throughout the life of each document. Make us your Standards Experts!
