As a result, the commercial dive business went into a slump. It was apparent that a number of maintenance jobs could be performed more efficiently with Ultrathermic equipment. Hence, Broco introduced Prime Cut, its surface exothermic tool. Shortly thereafter, other companies followed suit and introduced their own lines. Today's new generation of cutting equipment includes entries from Broco, Arcair, and Bell Systems.
Ultrathermic cutting is a derivative of oxygen arc cutting.
In oxygen arc, an arc is struck between an electrode and the metal to be cut. A molten weld pool is formed as a result of that arc. Oxygen, introduced through the hollow electrode, increases the temperatiure of the weld pool. In addition to the rapid melting, the pressure of the gas jets drives the molten metal away, forming the cut. What sets Ultrathermic apart from oxygen arc cutting is that once the arc is struck, the rod will continue to burn without maintaining an electric current.