Process for chromizing

Claim 1

A PROCESS SOF CHROMIZING FERROUS METAL WORK, WHICH COMPRISES PROVIDING A RETORT WHICH IS CLOSED WITH RESPECT TO THE ATMOSPHERE, PLACING IN THE RETORT FERROUS METAL WORK TO BE CHROMIZED AND CLOSING THE RETORT, INTRODUCING INTO THE RETORT A HALOGEN ACID GAS, INTRODUCING INTO THE RETORT A CARRIER GAS FREE FROM NITROGEN CONTAMINATION, MAINTAINING THE RETORT AND THE WORK AT A TEMPERATURE OF BETWEEN 1500* AND 2300*F., PROVIDING A SOURCE OF CHROMIUM OUT OF CONTACT WITH THE WORK, DISTRIBUTED IN A SERIES OF LAYERS THROUGH WHICH THE GAS CAN FLOW SEQUENTIALLY, THERE BEING A RATIO OF THE TOTAL SURFACE AREA OF THE SOURCE OF CHROMIUM TO THE TOTAL SURFACE AREA OF THE WORK WHICH IS BETWEEN 0.8 TO 1 AND 5 TO 1, MAINTAINING THE SOURCE OF CHROMIUM AT A TEMPERATURE BETWEEN 1500* AND 2300*F., PROVIDING A CHANNEL FROM THE SOURCE OF CHROMIUM TO THE WORK AND PROVIDING A RETURN SCHANNEL FROM THE WORK TO THE SOURCE OF CHROMIUM, CIRCULATING THE HALOGEN GAS AND THE CARRIER GAS IN ADMIXTURE UNDER POSITIVE PRESSURE SEQUENTIALLY THROUGH THE LAYERS OF THE SOURCE OF CHROMIUM AND THEN IN CONTACT WITH THE WORK TO CHROMIZE THE WORK AND THEN BACK THROUGH THE SOURCE OF CHROMIUM TO REGENERATE THE GAS, MAINTAINING THE CHROMIZING POTENTIAL HIGH BY WITHDRAWING FROM THE RETORT INCREMENTS OF CARRIER GAS AND HALOGEN AS AND MAINTAINING A SUFFICIENTLY LOW DEW POINT IN THE INLET GASES, SO THAT THE DEW POINT IN THE EXIT GAS IS NOT IN EXCESS OF +5*F., AND CONTINUING THE CIRCULATION OF THE GAS AND THE CHROMIZING FOR A TIME OF AT LEAST 5 HOURS.