Drop hardening: the process of dropping small cups and cones and all rollers directly from the drop hardeningfurnace into an oil bath which quenches them.
是指将小尺寸的外圈，内圈和所有滚动体直接从熔炉里抛到冷却油中进行淬火的工艺过程。
2
CYCLE time: Amount of time product spends in a furnace at specified temperature for the purpose of carburizing or hardening product.
周期：产品在炉中某特定温度下渗碳或硬化所需要的时间。
3
This paper investigates the rational decrease of hardening heating time of 45 steel parts in the box furnace.