Cast Shop Technology: Casthouse Management and Automation
Sponsored by: TMS Light Metals Division, TMS: Aluminum Committee
Program Organizers: David Gildemeister, Arconic Technology Center
Thursday 8:30 AM
March 2, 2017
Location: San Diego Convention Ctr
Session Chair: Jean Francois Desmeules, Dynamic Concept
8:30 AM Introductory Comments
Overpressure Due to a Molten Aluminum and Water Explosion in a Casthouse: Jennifer Woloshyn1; Andrew Gerber2; Tom Plikas1; Duane Baker1; Adam Blackmore1; 1Hatch Ltd.; 2Envenio Inc.
Explosions of molten aluminum and water are a potential, very serious safety risk in aluminum casthouses. Although prevention of these explosions is of paramount importance, understanding the overpressure resulting from an explosion is important to the design of blast-proof control rooms and protection of other equipment. Overpressure has traditionally been assessed using a simplistic principle of decreasing overpressure with distance, which neglects the significant, complex interactions of the blast wave with walls and other bodies. Computational fluid dynamics (CFD) modeling presents a method to analyze the problem in three dimensions. Blast analysis of a full casthouse with a conventional, commercial CFD code can be time-prohibitive. This paper presents a methodology to predict overpressure due to a molten aluminum- water explosion in a casthouse using an emerging CFD code – EXN-Aero by Envenio. Results for a typical casthouse are presented for use in the design of control rooms and other equipment.
Automation and Optimization of Sow Casting in Alouette: Jean-Francois Desmeules1; Jean-Benoit Néron1; Jean-Pierre Bérubé2; 1Dynamic Concept; 2Aluminerie Alouette Inc.
Sow casting in Alouette smelter have undergone many optimization projects in the past few years. In the cycle time critical path, actual pouring of the metal in the moulds from the crucibles remained one of the most important parts. This operation was done manually, leading to variability in duration as well as for sow weight. Sow caster capacity is a function of the average weight of the sows and a reduction of the standard deviation can help improve the average weight hence the capacity. A formula was developed to predict the quantity of metal transferred in function of the crucible tilt angle and an algorithm was built to optimize the pouring time. Implementation of the program was made in a very short time frame and the results show that a reduction of the pouring time as well as the weight standard deviation was obtained.
Radio Frequency Identification (RFID) Technology for the Aluminum Industry: Valerie Langelier1; 1Hatch
The current trend all industries are to maximize operation time so as to lower production costs. To achieve this goal, manual tasks such as data monitoring are being transferred so that they can be carried out by automated systems. Radio Frequency Identification (RFID) technology is one of these alternatives, where electromagnetic fields are used to automatically identify and tracks objects. The present paper will elaborate on the possible RFID applications for the aluminum industry using the projects currently being carried out at the Alcoa Deschambault and Baie-Comeau smelters as examples. The RFID system implementation in a metal environment and the major factors to consider during the design will be described. The paper will also describe the field tests performed at the Casthouse and Pootroom departments and a method to improve the metal time management and personnel safety.
9:55 AM Break
Semi Finished Products Traceability Improvement with Laser Marking: Jean-Francois Desmeules1; Benoît Côté1; Jean-Daniel Dufour1; 1Dynamic Concept
Parts traceability is becoming more and more important in many industries. Among others, automotive, military, aeronautics and medical industries have strict rules on parts traceability. Different marking technologies can be used to meet these requirements. Durability and reliability of the marking is very important. Also important is the automation of the marking process to avoid any human error in the procedure. Improved traceability is possible with lasers as compared to stickers and ink jet marking. A powerful, quick acting laser is now available but safety of the installation in an existing process is essential and it is one of the main design criteria. A successful integration of an equipment providing laser, ink jet and micro-percussion in an existing production line was made while complying to all safety and cycle time requirements.
Structural Integrity Assessment of Pressurized Ladles for Aluminum Smelting: Maher Al-Dojayli1; Pouya Zangeneh1; Alexandre Lamoureux1; Daniel Richard1; Pierre-Louis Allaire1; Hamid Ghorbani1; 1Hatch
Pressurized ladles, being closed, minimize aluminum dross due to oxidization and conserve energy required for ladle preheating. Design of pressurized ladles is not addressed by ladle design standards such as AISC Technical Report No. 9. This paper presents a design-by-analysis methodology for structural integrity assessment of pressurized ladles using finite element analysis and guidelines of ASME Boiler and Pressure Vessel Code. Transient temperatures in the ladle shell during preheating and aluminum charging / discharging are estimated and validated against site measurement data. Thermal loads are then combined with gravity loads (ladle self weight and molten metal charge) and ladle internal pressure at different pressurization, lifting and metal pouring stages. The resultant stresses and deformations in the ladle are compared with the ASME allowable limits against plastic collapse, thermal ratcheting and fatigue failures. This paper demonstrates the robustness of design-by-analysis methodology for integrity assessment of ladles under non-standard conditions.
Have Recent Advances in Direct Chill Casting Made Us Less Safe?: Alex Lowery1; 1WISE CHEM LLC
The frequency and severity of molten metal explosions in our industry has increased over the past decade. This paper considers if recent technology advances in direct chill casting processes resulted in our industry downplaying this hazard. Through analysis of past research studies, molten metal incident reporting data and review of the recent explosion that destroyed the Noranda Aluminium cast house. The causes of molten metal explosions are considered and explored in this paper. I argue that recent molten metal explosions could have been prevented if the past research studies’ conclusions were adopted as best practices.
11:25 AM Concluding Comments