Archive for the 'Stress Relieve' Category

August 25th, 2015 : Posted in Induction coils, Induction Hardening, Induction Heat Treating, Induction Heating, Induction Tempering, Long Lasting Inductors, Stress Relieve : Comments Off on Little Secrets for a Lasting Impression on Coil Life – Part 17: Inductors for heating internal surfaces   

______________________________________________________________________________________________ The May-July installments of the Professor Induction column discussed application specifics and some root causes of premature failures of inductors for heating internal surfaces, along with some tips to prevent such failures. This installment continues reviewing various failure modes associated with this type of inductor. Failure mode #4. Some inductor builders fabricate coils that […]

May 29th, 2015 : Posted in Automotive Heat Treat, Crankshaft Hardening, Induction coils, Induction Hardening, Induction Heat Treating, Induction Heating, Induction Tempering, Long Lasting Inductors, Stress Relieve : Comments Off on Little Secrets for a Lasting Impression on Coil Life – Part 15: Inductors for heating internal surfaces   

______________________________________________________________________________________________ The April installment of the Professor Induction series began to discuss specifics of the application and failure analysis of inductors for heating internal surfaces, potential causes of failure, and prevention of failure. This installment continues reviewing various failure modes associated with this type of inductor. Failure mode #2. In contrast to inductors used to […]

November 11th, 2014 : Posted in Automotive Heat Treat, Gear Hardening, Induction coils, Induction Hardening, Induction Heat Treating, Induction Heating, Induction Power Supplies, Induction Tempering, Long Lasting Inductors, Shaft Hardening, Stress Relieve, Tube and Pipe Heating : Comments Off on Little Secrets for a Lasting Impression on Coil Life – Part 10: Assuring fabrication quality   

______________________________________________________________________________________________ The heating inductor is one of the most critical components of any induction heating and heat treating system. In everyday practice, an inductor is also called an induction coil or simply a coil; however, its geometry often does not resemble, by any stretch of the imagination, the shape of a classical coil (Fig.1). The […]

October 1st, 2014 : Posted in Automotive Heat Treat, Crankshaft Hardening, Induction coils, Induction Hardening, Induction Heat Treating, Induction Heating, Induction Tempering, Long Lasting Inductors, Metallurgical Aspects, Stress Relieve : Comments Off on Little Secrets for a Lasting Impression on Coil Life – Part 9: Understanding copper wall thickness   

______________________________________________________________________________________________ The wall thickness of an inductor’s copper heating face should increase as frequency decreases. This fact is directly related to both current penetration in the copper and the copper edge effect (both effects were discussed in earlier installments), and it holds true for coils machined from solid copper as well as those made of […]

July 24th, 2014 : Posted in Automotive Heat Treat, Crankshaft Hardening, Induction coils, Induction Heat Treating, Induction Heating, Induction Tempering, Long Lasting Inductors, Magnetic Flux Concentrator, Shaft Hardening, Stress Relieve, Tube and Pipe Heating : Comments Off on Little Secrets for a Lasting Impression on Coil Life – Part 7: Coil End Effect   

______________________________________________________________________________________________ Nonuniform coil current density distribution resulting from various electromagnetic phenomena has a dramatic effect on induction coil life and crack development in the copper. Besides skin, proximity, and copper turn edge effect (discussed in previous columns of the Professor Induction series), coil end effect is another critical factor that should be taken into account […]

June 25th, 2014 : Posted in Automotive Heat Treat, Computer Modeling, Gear Hardening, Induction coils, Induction Hardening, Induction Heat Treating, Induction Heating, Induction Tempering, Long Lasting Inductors, Magnetic Flux Concentrator, Shaft Hardening, Stress Relieve, Tube and Pipe Heating : Comments Off on Little Secrets for a Lasting Impression on Coil Life – Part 6: Water-Cooling Specifics of Two-Turn Scan Inductors   

______________________________________________________________________________________________ Is it safe to simply scale down water-cooling requirements when designing smaller inductors? Does it make any difference how multi-turn (e.g., two-turn coil) hardening inductors are connected to water cooling circuits? Several best practices are associated with these seemingly simple questions. This article explores some of these tips, using a case study to illustrate […]

______________________________________________________________________________________________ When an alternating current flows through an electrical conductor (that is, bus bar or inductor leg), the current distribution is not uniform. Due to the skin effect, approximately 63% of the current will be concentrated within the surface layer of the conductor at what is called the penetration depth. Current penetration depth in copper, […]

______________________________________________________________________________________________ As it is with human lifetimes, so it is with induction coils—each has a certain ending, yet uncertain timing. I would now like to introduce a new article series. The goal of this series is to provide the induction heating community with both theoretical explanations and practical recommendations that will allow induction heating practitioners, […]

September 30th, 2013 : Posted in Automotive Heat Treat, Computer Modeling, Induction coils, Induction Hardening, Induction Heat Treating, Induction Heating, Induction Tempering, Long Lasting Inductors, Stress Relieve, Uncategorized : Comments Off on Application and Modeling of Pancake Inductors   

______________________________________________________________________________________________ Single-turn and multi-turn solenoid inductors are the most popular designs for induction heating of metals. In addition to these traditional designs, many specialized inductors have been developed to address specific features of a particular application, such as geometry of the workpiece, required heat pattern, material handling specifics, process parameters selection, and production rate. Specialized […]

November 20th, 2012 : Posted in Computer Modeling, Induction coils, Induction Heat Treating, Induction Heating, Induction Tempering, Joining Applications, Long Lasting Inductors, Magnetic Flux Concentrator, Stress Relieve, Tube and Pipe Heating : Comments Off on Computer Modeling of Heat Treatment of Steel Tube/Pipe Ends   

____________________________________________________________________________________________ Computer modeling is a powerful tool in developing novel technologies, helping to unveil process subtleties, determine optimal recipes, and improving existing technologies. An increasingly important function of computer modeling is determining the robustness of a particular induction heating system, revealing critical factors that affect temperature uniformity within the heated region, identifying ways to improve […]