PERIODIC ATMOSPHERE FURNACE MAINTENANCE: PART ONE PREVENTATIVE MAINTENANCE PLANS

摘要

How many times have you looked at atmosphere heat treated parts and been amazed by how poor their surface appearance is (Fig. 1), or visited a heat treat shop only to find critical components such as gears coming out of carburizing furnaces scaly with decarburized surfaces, coated with sludge, or blackened by oil stains? Well it doesn't have to be that way. A little furnace maintenance goes a long way toward improving both the image and the quality of heat treated parts and reducing the cost to produce them. In a well-maintained shop, parts come out of hardening and carburizing furnaces extremely clean, typically being gray-green in the as-quenched condition (Fig. 2). There is no evidence of loose soot, scale, or other contaminants on their surfaces, so a simple post-wash operation will suffice. Badly discolored parts, by contrast, are typically shot blasted, and even then may not clean up.