Restoration Of Copper Crucibles Proves To Be A Growing Business
If you’ve been in the Butech Bliss facility recently it’s likely that you’ve noticed copper being fabricated or machined. The copper-based melting equipment repair and replacement business has been steadily growing and gaining new customers. Butech Bliss has been able to utilize talents amongst our employees to service an industry that has sorely needed a reliable supplier over the last several years. The melting or “re-melting” of many specialty or exotic metals often takes place under controlled conditions inside of a water-cooled copper vessel. These vessels are typically a key part of melting systems known as VAR (Vacuum Arc Remelt), ESR (Electro-Slag Remelt), PAM (Plasma Arc Melting) and EBM (Electron Beam Melting). Butech Bliss has supplied both new components and repair services for all of these different systems.
The copper crucibles, liners and hearths are commonly used for the melting of titanium, nickel alloys, select stainless steels and exotics such as tantalum and vanadium. Some of these metals are initially melted in an induction furnace or electric arc furnace and poured into ingot molds. These ingots are then re-melted in copper crucibles as an additional step in the refinement process. This “re-melting” is often done under specific conditions that remove undesirable elements during the melting process and greatly improves the quality of the metals. In the case of titanium, the initial melting occurs in a copper hearth and the subsequent re-melting in a copper crucible both under strictly controlled environmental conditions.
One of the interesting characteristics of these copper vessels is the amazing ability to conduct heat away from the molten metals. Titanium, for example, melts at around 3000o F. The molten titanium is only separated from the cooling water by as little as ¾” of copper. The copper would normally melt at a temperature (2000o F) well below that of titanium, but copper is such an excellent conductor of heat that the cooling water prevents a meltdown. These severe conditions require frequent maintenance and repairs to be performed. The copper is frequently received in a distorted condition with gouges, scars and arc damage requiring welding, straightening or machining in order to be returned to service.
Butech’s role in the melting equipment business started with the repair and refurbishment of these vessels for existing Butech Bliss customers. Manufacturing of new copper–based components, plus engineering and design became a natural progression of our services.
