1、1 INCH-POUND I MIL-B-48589 (AR) AMENDMENT 3 17 June 1991 SUPERSEDING AMENDMENT 2 3 February 1981 MILITARY SPECIFICATION BODY ASSEMBLY: 11747350 (DAYLIGHT ) This amendment forms a part of Military Specification MIL- B-48589(MU), dated 31 December 1975, and is approved for use by the U.S. Army Armamen
2、t, Munitions, and Chemical Command, and is available for use by all Departments and - Agencies of the Department of Defense. PAGE 2 3.4.3, Delete and substitute: 113. 4.3 Vibration “A“ . Vibration shall be applied along each of three mutually perpendicular axes of the body assembly. The vibration sh
3、all be sinusoidal as follows: a. At a frequency. of 5 Hertz (Hz) , the acceleration shall be .5G rt 10%: During a frequency sweep of 5 to 9 Hz, increase acceleration linearly from .5 G to 1.5 Gs ? 10%. b. c. During a frequency sweep of 9 to 500 Hz, maintain constant acceleration of 1.5 Gs k 10%. Dur
4、ing a frequency sweep of 500to 9 Hz, maintain constant acceleration of 1.5 Gs k 10%. d. e. During a frequency sweep of 9 to 5 Hz, decrease acceleration linearly from 1.5 GIs to .5 G k 10%. f. At 5 Hz, acceleration shall be .5 G k 10%. The frequency of applied vibration shall be swept logarithmical i
5、n 15 minute k 1 minute sweep cycles for a total of two hours per axis. The body assembly shall show no evidence of physical failure subsequent to vibration. Following the vibration test, the body assembly shall meet the requirements of 3.2 and 3.5 through 3.16 inclusive.“ 1 OF 3 FSC 1240 Distributio
6、n Statement A. is unlimited. Approved for public release; distribution Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-B-48589 (AR) AMENDMENT 3 PAGE 3 3.4.4, Delete and substitute: “3.4.4 Vibration IfBir. Vibration shall be applied along each of
7、three mutually perpendicular axes of the body assembly. The vibration shall be sinusoidal as follows: a. At a frequency of 5 Hertz (Hz), the acceleration shall be 1.0 G k 10%. b. During a frequency sweep of 5 to 500 Hz maintain constant acceleration of 1.0 G k 10%. c. During a frequency sweep of 500
8、 to 5 Hz, maintain constant acceleration of 1.0 G f 10%. d. At 5 Hz, the acceleration shall be 1.0 G f. 10%. The frequency of applied vibration shall be swept logarithmically in 15 minute f. 1 minute sweep cycles for a total of 15 minutes f 1 minute along each of the three mutually perpendicular. ax
9、es (total vibration time 45 minutes f 3 minutes). The body assembly shall show no evidence of physical failure subsequent to vibration, Following the vibration test, the body assembly shall meet the requirements of 3.2 and 3.5 through 3.16 inclusive. 3.4,5, Delete and substitute: “3.4.5 Shock. The b
10、ody assembly shall be subjected to 24 cumulative shocks consisting of three each at 35 GIs f lo%, then 20 Gs k 10% applied in each direction along each of the two mutually perpendicular horizontal axes (all four sides). The shock pulse shall have a half sine wave with a time duration of 3 f .2 milli
11、secondk. The body assembly shall also be subjected to six cumulative shocks consisting of three each at 35 Gs 1 lo%, then 20 GIs k 10% applied in one direction along the vertical axis (normal operating position of the body assembly only). The shock pulse shall have a half sine wave with a time durat
12、ion of 18 k 3 milliseconds. The body assembly shall show no evidence of physical failure subsequent to shock. Following the shock test, the body assembly shall meet the requirements of 3.2 and 3.5 thorough 3.16 inclusive.i 2 Provided by IHSNot for ResaleNo reproduction or networking permitted withou
13、t license from IHS-,-,-ip1I i MIL-B-48589 (3) 12 7999906 0485851 II II MIL-B-48589 (AR) AMENDMENT 3 PAGE 4 * 3.6, Delete and substitute: l3.6 Sea1inq.- The body assembly shall show no evidence of leakage in excess of 0.1 pound per square inch (psi) when subjected to an internal pressure of 5. rt 0.1
14、0 psi for a minimum of 1 hour. The interior atmosphere of the accepted body assembly shall contain nitrogen having a dew point as least as low as minus 25OF at atmospheric pressure. The body assembly shall then be sealed with the dry nitrogen specified to an internal pressure of between 0.25 and 0.5
15、0 psig.“ PAGE 6 3.15.1, line 4, Delete second sentence and substitute: “When checked at the temperature condition specified in 3.4.2 the direction force shall not exceed 9.0 pounds (lbs) .II 3.15.3, line 1, Delete IIlO-lbs-ins, torque“ and substitute “10-15 lbs-ins, torque“. PAGE 15 * 4.6.6, line 2,
16、 Delete “0.25 to 0.50 and substitute “0.0 to 0.50“. NOTE: The margins of this amendment are marked with an asterisk or vertical lines to indicate where changes (additions, modifications, corrections, deletions) from the previous amendment were made. This was done as a convenience only, and the Gover
17、nment assumes no liability whatsoever for any inaccuracies in these notations. Bidders and contractors are cautioned to evaluate the requirements of this document based on the entire content irrespective of the marginal notations and relationship to the last previous amendment. Custodian: Army - AR Preparing activity: Army - AR (Project 1240-AB28) 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
