1、 - THE HISTORY AND RATIONALE OF MIL-STD-810 (EDITION 2) (“TEST METHOD STANDARD FOR ENVIRONMENTAL ENGINEERING CONSIDERATIONS AND LABORATORY TESTS”) Herbert W. Egbert January 2010 ABOUT THIS EDITION This document is a revision of the widely successful first edition of The History and Rationale of MIL-
2、STD-810. The author has provided editing marks in the left margins to indicate additions and modifications for those who wish to find this material quickly or to make comparisons with the previous edition. New material in Edition 2 includes background and analysis of MIL-STD-810G, the latest version
3、 of Test Method Standard for Environmental Engineering Considerations and Laboratory Tests, published in October 2008. i Table of Contents HISTORY AND RATIONALE OF MIL-STD-810, EDITION 2 .1 BACKGROUND .11 PART ONE.21 METHOD 500 - LOW PRESSURE.35 METHOD 501 - HIGH TEMPERATURE41 METHOD 502 - LOW TEMPE
4、RATURE.45 METHOD 503 - TEMPERATURE SHOCK.55 METHOD 504 CONTAMINATION BY FLUIDS (Formerly (in -810C and prior editions) “Temperature Altitude Tests”) 63 METHOD 505 SOLAR RADIATION (SUNSHINE) 67 METHOD 506 - RAIN.75 METHOD- 507 HUMIDITY .83 METHOD 508 - FUNGUS.93 METHOD 509 - SALT FOG.105 METHOD 510 S
5、AND AND DUST 111 METHOD 511 - EXPLOSIVE ATMOSPHERE 115 METHOD 512 LEAKAGE (IMMERSION) 127 METHOD 513 - ACCELERATION 129 METHOD 514 - VIBRATION135 METHOD 515 - ACOUSTIC NOISE 157 METHOD 516 - SHOCK 161 METHOD 517 SPACE SIMULATION.173 METHOD 517 - PYROSHOCK .175 METHOD 518 - TEMPERATURE ALTITUDE HUMID
6、ITY183 METHOD 518 - ACIDIC ATMOSPHERE.178 METHOD 519 GUNFIRE SHOCK (Formerly Gunfire Vibration) .182 METHOD 520 TEMPERATURE, HUMIDITY, VIBRATION, ALTITUDE186 METHOD 521 - ICING/FREEZING RAIN195 METHOD 522 BALLISTIC SHOCK .199 METHOD 523 VIBRO-ACOUSTIC/TEMPERATURE.203 METHOD 524 FREEZE-THAW 205 METHO
7、D 525 TIME WAVEFORM REPLICATION.207 METHOD 526 RAIL IMPACT .209 METHOD 527 MULTI-EXCITER TESTING 211 METHOD 528 MECHANICAL VIBRATIONS OF SHIPBOARD MATERIEL (Type I Environmental and Type II Internally Excited) 213 PART THREE WORLD CLIMATIC REGIONS GUIDANCE 215 ANNEX A - Major Changes from MIL-STD-81
8、0F to MIL-STD-810G.A-1 - ii - ANNEX B - ANTICIPATED FUTURE CHANGES AND CORRECTIONSB-1 ANNEX C - WEATHER AND CLIMATIC EXTREMES A Brief Summary C-1 1 THE HISTORY AND RATIONALE OF MIL-STD-810, EDITION 2 by Herbert W. Egbert1January 2010 FOREWORD In October 1965, Mr. Virgil J. Junker2, a project enginee
9、r with the Vehicle Dynamics Division, Flight Dynamics Laboratory, Research and Technology Division, Air Force Systems Command, Wright-Patterson Air Force Base, Ohio, published a report titled “The Evolution of USAF Environmental Testing,” Technical Report AFFDL-TR-65-197. The report presented “suppo
10、rting data and background information on the origination and development of natural and induced environmental tests intended for United States Air Force (USAF) aerospace and ground equipment.” At that time, MIL-STD-810A, “Military Standard, Environmental Test Methods for Aerospace and Ground Equipme
11、nt” was, in effect, an Air Force document. MIL-STD-810 has since progressed through six (6) revisions (MIL-STD-810B being the first Tri-Service version), with -810G being the sixth and “new kid on the block.” Please note that, as of this writing, MIL-STD-810G has been on the street for some 14 month
12、s. My procrastination in writing this update results in continued work on “fixing” changes to -810G for Change Notice 1, and an effort to capture at least some of the changes or anticipated changes in this paper. We now estimate Change Notice 1 will be available for review in September or October 20
13、10. As a point of information, I began writing the original paper somewhere around 1996, with the intent of capturing what I knew or could obtain concerning the evolution of MIL-STD-810F. I began my government career in 1970 at the US Army Electronic Proving Ground, Fort Huachuca, AZ. After one year
14、 as a project officer, I transferred to the Environmental Test Facility where I became immersed in MIL-STD-810 (-810B at that time) and environmental testing. After nine years I moved to the Test and Evaluation Commands Headquarters at Aberdeen Proving Ground, MD, where I assumed the responsibility
15、of Army Custodian for -810 (transferred from CECOM at Ft. Monmouth, NJ). After working with Tri-Service personnel through several iterations of -810, I offered to take over Tri-Service management of MIL-STD-810F (with Wright-Patterson Air Force Base retaining the “Preparing Activity” status). My int
16、ent was to prepare a document that was not only totally written in the same style, but also to try and make it a more user-friendly document. 1I have included numerous comments and other text submitted by friends and associates, hence, I cannot take full credit for this document. 2I had the pleasure
17、 of speaking with Mr. Junker in the summer of 1999, and later found out that he passed away on 26 Oct 99. He had remembered his paper and was interested in what I have been preparing. Following his passing, Mrs. Junker noted that she supported my effort, and that she would like a copy of the origina
18、l paper when completed, and that was accomplished. She later responded that she and their children appreciated reading it. Disclaimer: Any views presented in this paper are those of the author and contributors, and do not necessarily represent the views of DOD or its components. 2 - Although still a
19、 government document, it is not specifically focused on military equipment, and I removed essentially all use of the term “military.” Anyhow, on 1 October 2002 I retired from the Government, and began working as a Government contractor. This document, therefore, has been written both while I was a G
20、overnment employee, as well as essentially on my own time, or as a contractor for my old office at Aberdeen Proving Ground. This paper includes both expanded information from the original paper, as well as information from MIL-STD-810G and some changes to be included in Change Notice 1 to -810G. Its
21、 interesting to note the sheer growth in size of MIL-STD-810 from the original -810 on 14 June 1962 with 66 pages, to the latest version, MIL-STD-810G (31 October 2008), with 804 pages, and using the same smaller font to save space! This time (post -810F) the changes can, for the most part, be attri
22、buted to not only clarification, definitions, and technical updates, but to five “new” environments with associated test methodology - things that took Virgil Junker and me (with a lot of outside help) almost 250 pages to explain! In addition to the “new” methods, I personally feel that a large amou
23、nt of the expanded text resulted from improper interpretation and improper use, and the authors of various editions of -810 trying to cover all bases. (I say “new” because the Rail Impact test was removed from Method 516, and created as a new Method 526, and included with several other new Methods a
24、s mentioned below.). Tailoring and common sense by users were often ignored, and it continues to this day. One of the biggest challenges in writing the original edition of this paper was finding information that tracked the evolution of the early versions of MIL-STD-810. In addition to Mr. Junkers w
25、onderful paper, one boon (for me) was that on March 11, 1975, the Chesapeake Chapter of the Institute of Environmental Sciences sponsored a seminar on MIL-STD-810C (10 Mar 75) in Baltimore, MD. This was my first real introduction to some of the experts in the environmental test field such as David A
26、skin, Dr. Bill Brierly, Dr. Al Burkhard, Hank Caruso, David Earls, Jack Gott, Burk Senn, Irv Gringorten, and so on. The Proceedings were later published and, upon my retirement from the Army Developmental Test Command on October 1, 2002, I located the 1975 Proceedings while cleaning out my files. I
27、have cited the Proceedings throughout this paper wherever appropriate. In it, David Askin was quoted as saying that “About eight years ago MIL-STD-810B was published. It was basically a minor revision of MIL-STD-810A, which had been in existence for four to five years before that. MIL-STD-810A (14 J
28、un 62) and MIL-STD-810B (15 Jun 67) were oriented to Air Force and Navy type aircraft equipment and specifically earmarked as an Equipment General Specification.” (In fact (as I mentioned earlier), MIL-STDs -810 and -810A were USAF documents; MIL-STD-810B was the first Tri-Service version of -810.)
29、A committee of experts was created to determine to what extent the numerous existing military standards could be standardized. It was noted that there is no standard that is applicable to everything in any field. One of the primary prerequisites for using MIL-STD-810C was good common sense and good
30、engineering judgment in the application of the document picking from it what is applicable to the particular problem. The MIL-STD-810C committee decided on several basic concepts, one of which was to put into MIL-STD-810C some leniency, or the allowance for any design group to either use the limits
31、that were in -810C with each of the test methods, or to select their own limits if they had justifiable reasons. (In fact, this option has been available since 3 the original -810 (1962) that had an up-front statement “WHEN IT IS KNOWN THAT THE EQUIPMENT WILL ENCOUNTER CONDITIONS MORE SEVERE OR LESS
32、 SEVERE THAN THE ENVIRONMENTAL LEVELS STATED HEREIN, THE TEST MAY BE MODIFIED BY THE DETAIL SPECIFICATION.”). One of the more significant overall changes in -810C (in the climatic area) was the introduction of a concept of operability during testing. The test engineer or designer had the option to s
33、elect some place during a test procedure when he could operate the equipment in the chamber, and make the necessary measurements to determine whether or not the equipment could operate at the extreme of the environment. MIL-STD-810B and other such documents required operation before and after the te
34、st, but not during it. Also added to -810C was a definition of some of the most common failure criteria that can be expected, as well as a brief recommended area of application. During the development of -810C, there was much discussion and thought of creating a “MIL-STD-811” that would contain envi
35、ronmental criteria; spell out the environmental limits and explain how to use them, and spell out the failure criteria and show how to use them. Unfortunately, this never came about mainly because the state-of-the-art was such that specification writers could not specify military test methods for -8
36、10C without some explanatory information at the beginning of the document so that the test engineers would be able to use the document intelligently. Many have questioned the numbering system used for the individual methods in the various editions of -810, i.e., 504.3, 514.5, etc. Based on text in t
37、he 1975 Proceedings, I assumed this originated with the -810C Committee. They decided that, in the future, changes to individual test methods or procedures could be simplified by merely re-issuing the revised method with numbering that reflects the change number, i.e., 500.1, 500.2, etc. This would
38、obviate the need to revise the entire document. However, in the original -810, the intent was to assign letters to each revision of individual test methods, i.e., 500, 500A, 500B, etc. Contrary to what I assumed from the 1975 Proceedings, MIL-STD-810A was, in fact, the first document to reflect the
39、current numbering system. The transition from MIL-STD-810C to MIL-STD-810D (19 Jul 83) was one of the more significant, in that -810D focused more on “tailorability” - a concept promoted by the “Shea Report.” This document was the “Report of the Task Force on Specifications and Standards,” March 7,
40、1977. Dr. Joseph F. Shea, Senior Vice President of the Raytheon Company chaired the Task Force. The report noted basic problems with Department of Defense (DoD) specifications and standards in that they centered more on application and enforcement, rather than with the detailed content of the docume
41、nts. Past versions of MIL-STD-810 contained up-front statements to the effect that users should modify the tests if the anticipated conditions would be more or less severe than those addressed in the standard. As I mentioned earlier, MIL-STD-810 (USAF), 14 June 1962, noted in paragraph 1.2 in upperc
42、ase letters that “WHEN IT IS KNOWN THAT THE EQUIPMENT WILL ENCOUNTER CONDITIONS MORE SEVERE OR LESS SEVERE THAN THE ENVIRONMENTAL LEVELS STATED HEREIN, THE TEST MAY BE MODIFIED BY THE DETAIL SPECIFICATION.” This, in effect, prescribed tailoring, but there was little other guidance to explain the coo
43、kbook parameters provided, i.e., the significance of a parameter, or options for 4 - changing it. The result was to test by rote. I also emphasize here that MIL-STD-810 test methods are not intended for component/material testing or for safety testing (e.g., munitions) but, in some cases, they could
44、 be appropriately tailored and applied. Mr. Henry (Hank) Caruso, at that time a Fellow Engineer at Westinghouse Electric Corporations Product Qualification Laboratory, Baltimore, MD, had published a number or articles on environmental testing, including a series of articles in the Institute of Envir
45、onmental Sciences (now known as the Institute of Environmental Sciences and Technology (IEST) Journal of Environmental Sciences from the March/April 1985 edition through that for November/December 1985, that highlighted the more significant changes from -810C to -810D. During my final preparation of
46、 the original version of this paper, I tried to capture the more significant changes from Hanks articles. In 1990, Hank published a four-part change comparison in the Journal, but this time for MIL-STDs-810D and -810E. In the March/April 1993 edition of the Journal, Hank and I published a similar ar
47、ticle highlighting the major changes from MIL-STD-810D to MIL-STD-810E. Hank coined the phrase “sacred cow” for those parameters that had been previously used (on a continuing basis) without consideration of their significance, and from which users had a difficult time departing. From Hanks IES Jour
48、nal article of March/April 1985, I extracted the following: “Overall, MIL-STD-810D was the result of a cooperative effort between representatives from industry and each of the three military Services working together for several years.” “significant changes were made that encourage the involvement o
49、f the environmental engineering specialist, and the tailored application of realistic criteria whenever possible. On these points there seemed to be a strong consensus of all parties involved.” The Summer 2001 edition of the IEST Journal contained a general comparison of MIL-STD-810E versus MIL-STD-810F procedures. In his
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