What On Earth Is This?

Recently we did an appraisal of some operating heat treat furnaces which included a number of vacuum furnaces. Amongst the items we looked at was this furnace, one which still has us scratching our heads. At first glance it appeared pretty standard, an older VFS vacuum furnace-really nothing out of the ordinary until we looked at the chamber itself which in big letters says “AGF”. Now AGF “American Gas Furnace Company” we are familiar with having seen a number of rotary retort furnaces the company has built over the years (although we believe the company is gone with anything left now belonging to Pemberton Fabricators). We have never heard of AGF building a vacuum furnace or even a chamber so where this system originated from is anybody’s guess.