A-A-52155 Engine Accessory Drive V-BeltsThis CID covers requirements for standard and heavy duty V-type engine accessory drive belts of various lengths and belt widths. The belts are either plain or notched or cogged base.

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A-A-52155B

TABLE II.  Fatigue test loads.

3.4.2  Resistance to temperature.  The belts shall not break or require more torque than specified in table III when subjected to temperature extremes of plus 150 degrees Fahrenheit (°F) and minus 20°F under the following conditions:  Place the unrestrained belt in a heat chamber in a horizontal position so that it does not contact the sides of the chamber.  Next subject the belt to

150 +2°F for 12 hours duration followed by 30 minutes cooling at ambient temperature. Following the cooling period, place the belt on the same pulley arrangement used for the fatigue test (see 3.4).  Apply and set tension to the belt equivalent to the tension applied when measuring the belt per SAE J636 (see 3.2).  Next, subject the assembly to -20°F for 12 hours duration and while still at the cold temperature, rotate the drive pulley not less than 2 revolutions.  Measure and record the torque required to start and to continue rotation.

TABLE III.  Maximum torque requirements.

3.4.3  Oil resistance.  When "oil resistant" is specified (see 7.3), the belt thickness shall increase no more than 20 percent nor decrease more than 1 percent when immersed in ASTM oil No. 1 and ASTM IRM 903 oil as cited in ASTM D471 under the following conditions:  Immerse two

7.6 mm (3 in.) long sections of hose in 70°C (158°F) oil bath for 22 hours.  The average of three measurements-the center point and 2 inch from each end shall constitute the thickness.

3.5  Age.  When specified (see 7.3), the age of the belts shall be not more than 12 months

(4 quarters) old from the time of manufacture to the date of acceptance by the Government.

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