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Locating Engineering Standards
U.S., international and foreign standards may be ordered from:
- Global Engineering Documents company at phone: 800-854-7179 or fax: 303-397-2740 or web site: http://www.global.ihs.com.
- NSSN of the American National Standards Institute (ANSI) at phone: 212-642-4980 or fax: 212-302-1286 or web site: http://www.nssn.org.
- By contacting a Standards Developing Organization who directly offers their standards. Note: AMT members may order any ANSI B11 series machine tool safety standard from the AMT Web site page ANSI B11 Standards. AMT members are also entitled to a 10% discount on other standards directly through ANSI.
If you have specific questions regarding standards, contact Dave Felinski, AMT Safety Director, at dfelinski@AMTonline.org or 703-827-5211.
U.S. Engineering Standards for Machine Tools
The American Society of Mechanical Engineers (ASME) is the Standards Developing Organization (SDO) for the American National Standards Institute's ANSI/ASME B5 series of engineering standards for machine tools. These standards cover a wide range of components and machine tools of interest to membership.
For more information on these standards, or an understanding of how you can participate in this standards development activity, contact ASME at 212-519-8018 and ask for the ASME B5 Standards Administrator.
JIC Standards
JIC (Joint Industrial Council) Standards were written in the early 1950s by a joint committee of major machine tool builders and users. The purpose was to provide a uniform set of basic practices which would result in a well-built machine tool. Four standards were written: Electrical (EMP-1-67/EGP-1-67); Electronic EL-11-1971); Hydraulic (H-1-1973); and Pneumatic (P-1-1975).
During the 1980s, the JIC committees became dormant and AMT (NMTBA at the time), which served as the secretariat for these committees, contacted the National Fire Protection Association (NFPA) to update and incorporate the JIC electrical standards into their standards development activity. Also, the National Fluid Power Association (NFPA) was contacted regarding the update and incorporation of the hydraulic and pneumatic standards into their standards work.
As a result of this effort, the National Fire Protection Association issued the NFPA 79 Electrical Standard for Industrial Machinery, and the National Fluid Power Association published Hydraulic Fluid Power - Systems Standard for Stationary Industrial Machinery (ANSI/NFPA/JIC T2.24.1) and Pneumatic Fluid Power - Systems Standard for Industrial Machinery (ANSI/B93.114M).
The NFPA 79 "Electrical Standard for Industrial Machinery - 2007 Edition" is now available at the National Fire Protection Association (NFPA) website (http://www.nfpa.org).
Copies of the now obsolete JIC standards are no longer available. All of the superseding standards can be obtained from:
- - NSSN of the American National Standards Institute (ANSI) at phone: 212-642-4980 or fax: 212-302-1286 or website: www.nssn.org.
- The standards originating organizations NFPA (electrical), phone: 617-770-3000 or 800-344-3555, and NFPA (fluid power), phone: 414-778-3344, or website: www.nfpa.org.
European Union (EU) Electromagnetic Compatibility Directive (Effective January 1, 1996)
The word compatibility in this EU directive means the machine will function in a safe and intended manner without introducing electromagnetic disturbances into its environment. In addition, the directive speaks of immunity, which means the machine will operate in a safe and intended manner without being affected by the presence of electromagnetic disturbances. Disturbances can be either radiated or conducted.
Machine builders can choose either of two options to comply with the directive:
The manufacturer may self-certify by referring to conformance with certain harmonized standards such as EN50081-2 and EN50082-2. These are European, CEN standards. In addition, due diligence must be shown by reference to good wiring practices (grounding, shielding, etc.). Incorporated components on the machine that come under the directive should be CE marked, and supported by a letter of conformity. All of this information should be documented in the Technical Construction File as required by Annex V of the EU machinery Safety Directive (89/392/EEC as amended).
A competent body can certify the machine by inspecting the above documentation, or by testing the machine.
For equipment as large as machine tools, there is discussion and controversy concerning the requirement for an actual test of the whole system. The document inspection portion of option 2 is a safe route until the smoke clears on procedures. At the time of this writing, German builders are using option 1.
For additional information, contact Paul Warndorf at pwarndorf@AMTonline.org or 703-827-5291.
ISO 230-2:2006 NC Positioning Standard Revised
This standard supersedes and replaces the old AMT (NMTBA) "Definition and Evaluation of Accuracy and Repeatability of Numerically Controlled Machine Tools," as well as the German VDI/DGQ 3441 on the same subject.
The "Test code for machine tools-Part 2: Determination of accuracy and repeatability of numerically controlled axes" ISO 230-2: 2006 can be purchased from:
- Global Engineering Documents company at phone: 800-854-7179 or fax: 303-397-2740 or http://www.global.ihs.com/
- NSSN of the American National Standards Institute (ANSI) at phone: 212-642-4980 or fax: 212-302-1286
The revised standard reflects new thinking behind the statistical approach to accuracy and repeatability; the previous assumption of random (Gaussian, bell-shaped or normal) distribution of programmed target hits has been abandoned. The new thinking reflects newly-acquired knowledge about factors affecting accuracy (e.g., friction, thermal effects, etc.), some of which could be controlled. Consequently, one does not deal with "standard deviation" (sigma) but rather with "standard uncertainty" (term used from the theory of uncertainty of measurement).
Another major change in the new standard is that instead of using 3 "standard deviations" (old standard), 2 "standard uncertainties" are used in line with a host of other characteristics when reporting the resulting accuracy and repeatability. The calculation for "standard uncertainty" is the same as for "standard deviation."
For additional information contact Paul Warndorf, AMT’s Vice President–Technology, at 703-827-5291 or e-mail: pwarndorf@AMTonline.org.
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