1999 FIN – IFI Introduces Third Edition of Its Metric Guide

February 09

00:00 2011

Share it With Friends

Can You Define 30 Basic Terms?

“To become reasonably thread friendly, a person must become familiar with about 30 basic terms,” according to the introduction to screw threads in Metric Fastener Standards. “Experts probably relate to 125 or more features or characteristics.”
The introduction to the metric screw threads section seeks “to explain in ‘layman’ terms some concepts which will assist in a fuller understanding of screw threads.”

Are you and your staff “reasonably thread friendly?” Try defining the following terms:

Screw thread, external threads, internal threads, root, crest, flank, fundamental triangle, major diameter, minor diameter, symmetrical thread, half-angle of thread, complete (or full form) thread, incomplete thread, thread pitch, pitch cylinder, thread axis, basic thread profile, fundamental deviation, allowance, maximum material condition, tolerances, minimum material condition, fit, clearance fit, interference fit, length of thread engagement, depth of thread engagement, tensile stress area, thread root area and thread shear areas.

August 2, 1999 FIN – It is not the book that you want to curl up with beside the fireplace for an evening of readying, but the new Industrial Fasteners Institute’s third edition of its Metric Fastener Standards is a vital volume for your fastener reference shelf.

Edited but the IFI’s chief engineer, Charlie Wilson, the book is divided into 12 sections, including eight product section and four that discuss screw threads and gaging practices, materials, technical data, and quality assurance.

The six-pound, 11-ounce tome is more than lists and drawings of endless standards. The chapter on screw threaded characteristics begins by noting that the “IFI has prepared an introduction to this section to explain in ‘layman’ terms some concepts which will assist in a fuller understanding of screw threads.”

The IFI is working on a CD-ROM version of the book to be released next year.

The $140 hardcover book features the image of a world map in the background to emphasize the international nature of metrics.

Joe Greenslade, who has reviewed fastener reference books in the past to create his list of recommended guides for a distributors reference shelf, told FIN the new IFI volume is “an excellent metric resource” which “pulls a lot of information together, as have previous IFI books.”

In addition to fastener manufacturers and distributors, Greenslade recommended that “OEMs designing new metric product should use it.”

Greenslade suggested that “most fastener suppliers should also have an ISO fastener standards guide in their library. The IFI book contains ASTM, ASME, SAE and IFI standards, but not ISO.

Text Features Change.

Each chapter includes a summary of changes since previous editions.

Notes throughout explain industry changes. For example, Metric Fastener Standards notes in the beginning of the Metric hex cap screw section that the ASME B18 Standards Committee in 1997 approved new quality assurance and dimensional conformance language.

Organic coatings and hydrogen embrittlement risk management also are topics in the new edition.

The book uses bold print to differentiate ISO and other standards. It includes comparisons between ISO and ASME standards for information purposes.

New in the metric guide are quality assurance standards, standards for organic and inorganic coatings, torque-tension relationship tests and a discussion of hydrogen embrittlement risk management.

The edition, which totals more than a thousand pages, includes documents on screw threads, materials, bolts, screws, studs, nuts, locking fasteners, structural bolting, slotting and recessed screws, socket screws, blind & small solid rivets, pins & washers, technical data and quality assurance information.

The new edition of the original 1976 Metric Fastener Standards was the result of “an IFI decision in 1971 to develop a globally acceptable system of metric engineering standards for mechanical fasteners which would be highly efficient and other significant improvements for fastener users and producers alike,” immediate past IFI chairman Bill Springer and chairman John O’Brien wrote in the forward.

The book comes with the requisite disclaimer that “the reader should understand that standards are living documents which are constantly under review and possible revision. Changes are usually the result of experience which indicates that a change(s) is desirable. The standards included are presented at a given point in time.” ©1999/2011 Fastener Industry News

Global Fastener News