Birchwood Technologies’ Presto Black cold metal blackening is formulated to produce a uniform depth of blackness and corrosion resistance, making it a well-suited finish for oil and gas drilling components. It is recommended for blackening cold- and hot-rolled, alloy and tool steels, as well as cast iron, forged steels and powdered metal. (It will not blacken stainless steel.)
According to the company, Presto Black is a fast, room-temperature process that provides high corrosion resistance for as many as 1,200 hours humidity exposure, without the hazards of the hot oxide process. It offers a uniform 0.000030" (1-micron) thickness, and for extra corrosion protection without chipping or peeling, its porous crystalline structure makes it an absorbent base for a rust-preventative topcoat.
Using Birchwood’s ion exchange system, the Presto Black process also operates with zero discharge of heavy metals to the drain. This system cleans and purifies the process rinse waters so they can be re-used rather than sent to the drain.
Presto Black is available for use in existing tank lines or in one of Birchwood’s modular tank systems.