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Heat Treated Fasteners Blackened In Bulk With Non-Polluting TRU TEMP® Black Oxide

Eden Prairie, Minnesota: Now there's a better In-House method for finishing heat treated fasteners to achieve an attractive and protective black oxide surface. The TRU TEMP® system produces a high quality, non-dimensional black finish - directly over light heat treat scale - on all types of fasteners and other bulk-handled parts.

Since the TRU TEMP process operates at only 200°F, it avoids the severe splattering and boilover hazards often seen with conventional hot oxide tanks. The relatively mild solutions used in the process line also prevent the formation of red coatings and white salt leaching that often plague ordinary black oxide finishes.

Small parts are best handled in a rotating process barrel for greatest economy. When rotated at 1-2 rpm, these barrel systems efficiently blacken the parts without scuffing the edges.

Compared to other finishing methods, the TRU TEMP process is fast and economical - processing time is only about 25 minutes and typical chemical cost is about $.01 per pound of finished parts.

Because the TRU TEMP process contains no EPA regulated chemicals, there is usually no need for waste treatment equipment. In most sewer districts the rinse waters are considered sewerable as non-hazardous effluent. This feature simplifies the installation and minimizes the capital investment needed to set up the process line.

The TRU TEMP process is an effective blackening tool for all types of bulk handled parts, such as threaded fasteners, screw machine parts, stampings, forgings and even MIM parts. Many larger pieces can also be successfully bulk processed, in stationary baskets, as long as they can be stacked to drain well and avoid flat-against-flat part contact.

The TRU TEMP process is ideal for all dimensionally critical parts and meets military specification MIL-DTL-13924 Class 1, and AMS 2485. The process also makes ISO compliance easier by keeping the finishing process in-house where part quality and inventory control is better managed.