Accession Number : AD0860157

Title :   Initial Production Test of Drier-Mixer, Bituminous-Concrete Materials, Modified.

Descriptive Note : Final rept. 3 Apr-26 Jun 69,

Corporate Author : ARMY ARMOR AND ENGINEER BOARD FORT KNOX KY

Personal Author(s) : Becker, Roger E. ; Collins, Steven T.

Report Date : 26 AUG 1969

Pagination or Media Count : 73

Abstract : The test objective was to determine if the previous test deficiencies and shortcomings had been corrected by modification and that modifications made to the item had not adversely affected performance. The test item was operated a total of 64 hours (44 hours asphalt production, 4 hours concrete production, and 16 hours miscellaneous operations). The test item was towed a total of 761 miles (616 over primary roads, 145 over secondary roads). The test item failed to satisfy essential criteria with respect to insulation, enclosure, or guarding of components with high operating temperatures; maintainability; functional suitability (output capacity); and reliability, to include roadability. Eight deficiencies and seven shortcomings were noted. The maintenance ratio was 0.76 man-hour of maintenance for each hour of operation. The mean time between failures (MTBF) was 10.7 hours. The mean time to repair failures (MTTR) was 4.7 clock-hours. The reliability at a 90-percent confidence level for a 10-hour mission was 19.7 percent.

Descriptors :   *CONCRETE), (*ROAD BUILDING EQUIPMENT, ACCEPTABILITY), (*ASPHALT, MIXTURES, DRYING, RELIABILITY, SAFETY, SAND, FUEL CONSUMPTION, GRAVEL, AIR COOLED, PORTABLE EQUIPMENT, DEFECTS(MATERIALS), TRAILERS, HUMAN FACTORS ENGINEERING, MAINTAINABILITY, TEST METHODS, MANPOWER, ROAD TESTS, STORAGE.

Subject Categories : Construction Equipment, Materials & Supplies

Distribution Statement : APPROVED FOR PUBLIC RELEASE