Mesh belts come in all shapes, sizes, materials and weaves and are used for such diverse applications as case hardening, brazing, sintering and glass-to-metal sealing to name a few. Belts run at temperatures from near ambient to several thousand degrees. They are expected not only to work in the furnaces but also for external part conveyance or in water, oil, brine, polymer and salt quench tanks. Mesh belts are exposed to a multitude of furnace atmospheres ranging from air to pure hydrogen and can be exposed to oxidation, sulfidation, carburization and nitriding. They operate in environments spanning dew points from below -100°F to above +100°F. And most of us expect our belts to perform well beyond normal expectations. How do they survive, and how can we make them last even longer? Let’s learn more.
If as a result of plating or other operations you suspect that hydrogen absorption has taken place in a part, it need not be a permanent condition. If cracking does not occur and the environmental conditions are changed so that no hydrogen is generated on the surface of the metal, the hydrogen can re-diffuse out of the steel and part ductility can be restored.
For the heat treater, the concept of hardenability is often more difficult to grasp than that of hardness. Part of the reason for this is that we seldom perform the tests that measure or predict this property in our shops. The reason why it is important to measure the hardenability of steel is to make sure that we are making the right material choice for a specific engineering application. With the supply of raw material coming from multiple worldwide sources, there is renewed emphasis on predicting how a material will respond to heat treating. Let’s learn more.
The 2007 Edition of NFPA 86 (Standard for Ovens and Furnaces) defines a Class C Furnace as one that “has a potential hazard due to a flammable or other special atmosphere being used for treatment of material in process.”
For the heat treater, the concept of hardness is well known and the act of hardness testing routine. In fact, it is so repetitive that at times it is taken for granted, leading to sloppy procedures and false readings. Today, the ability to test that the heat-treating processes have achieved the proper hardness is more important than ever. Let’s learn more.
A wise man once said that anything worth doing is worth doing right. In the case of carburizing, this is especially true since, from both an engineering and a heat-treating perspective, we often take the process for granted – a dangerous precedent that can get us in big trouble. It’s time to review the basics. Let’s learn more.
Heat treaters have been searching for ways to simplify furnace temperature uniformity surveys. Using proven technology developed in the ceramics industry, this is now a reality. With emphasis today on the importance of meeting the requirements of AMS 2750D, CQI-9 and Nadcap, the heat-treating, brazing and sintering industries now have a tool to help them focus on the uniform and efficient delivery of heat to their products to ensure consistent and repeatable quality.
The Doctor has been making house calls and has found a disturbing trend – far too many heat treaters do not understand the function, design, adjustment or safe operating requirements for their flame curtains. It’s time to review a subject too often taken for granted. Let’s learn more.
Check out the October 2019 issue of Industrial Heating, featuring the "High-Temperature Refractory Maintenance", "How to Tell if You Really Have an Abrasion Problem", "Direct-Fired Gas Burners for High-Temperature Applications", and much more.