Analysis and Recommendation of Core Annealing Furnace Designs
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The batch-process electric bell annealing furnace currently used by Carte International Inc. is outdated and is believed to be operating at below acceptable efficiency. The authors of this report have been contracted to assess the condition of the current furnace and recommend a course of action including the recommendation of a new replacement furnace. A Failure Modes and Effects Analysis (FMEA) identified seven key failure risks in the current system. These failure modes are identified as: core oxidation, foreign contamination, failure to achieve soak temperature or time, overheating of cores, non-uniform temperature distributions, thermal shock, and general safety. Further work was performed to collate available data on the construction, history, maintenance, and operation of the existing furnace to assist future analysis by the Client. Finally, an experimental analysis was planned and arranged for the Client to test for the presence of non-uniformity in operating temperature distributions within the current furnace. Due to long lead-times on equipment acquisition this experiment could not be performed in time for this report; however, it will be carried out by the Authors in the coming weeks. In parallel, theoretical work was undertaken to establish a cohesive set of client needs and metrics which were used to adjudicate various proposed replacement systems. Five quotes were obtained from various suppliers consisting of variations on two key furnace designs: a new (replacement) bell furnace, or a switch to a single-piece workflow rolling hearth furnace. Each was compared against the generated client needs. The final analysis indicated that based on currently available data a switch to single-piece workflow is not cost effective due to the large capital cost and space requirements of rolling hearth furnaces. Replacing the existing furnace with an updated, high efficiency bell furnace is recommended. Current operations and growth projections are directly on the boundary between batch-optimal and single-piece-optimal conditions. Should production or growth projections be revised upwards, single-piece workflow systems would become preferable. As such, a full description of a recommended rolling hearth design is also included as an alternate proposal that can be pursued should further data become available that countermands the above conclusions.