Production Trenching

摘要

Equipped with standard digging arms (10 feet 10 inches) and identical heavy-duty, 48-inch-wide, 2-cubic-yard buckets, the test units dug to 10 feet and a bucket-width wide for 30 minutes in their heavy-digging mode. The operators then switched machines and repeated the process. Total trench opened exceeded 550 feet. Since both machines worked an hour, measuring the two respective trenches for each and calculating the ex-cavated volume yielded a per-hour production number. Comparing these numbers, we noted an approximate 5-percent differential, which we consider too small for making judgments about machine productivity; variability in the particular machines used, in soil conditions and in operator performance could easily push the numbers in the opposite direction on another day. Thus, we concluded that the productivity of the two units was essentially equal.