Computational and experimental failure analysis of continuous-annealing furnace radiant tubes exposed to excessive temperature

Dini, Ghasem; Vaghefi, Sayed Mahmoud Monir; Lotfiani, Mostafa; Jafari, Morad; Safaei-Rad, Mohammad; Navabi, Morteza; Abbasi, Shahram

doi:10.1016/j.engfailanal.2007.05.007

Cited by 25 publications

(5 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Also, the tube bends showed higher magnitudes of stress than the straight sections. Similar investigations were carried out by Dini et al [25] on P-type radiant tubes of a CGL furnace. However, it is not practical to obtain experimental measurements for each radiant tube application.…”

Section: Early Macroscopic Studiessupporting

confidence: 66%

Influence of Surroundings on Radiant Tube Lifetime in Indirect-Fired Vertical Strip Annealing Furnaces

et al. 2020

View full text Add to dashboard Cite

The effects of surrounding radiation—emanating from radiation exchange with neighboring partners in indirect-fired vertical strip annealing furnaces, such as the other radiant tubes, the passing strip, and the enclosing furnace chamber—on the radiant tube lifetime were studied. In-house developed and validated numerical models were used to calculate the thermomechanical behavior, especially creep deformations and the corresponding stresses as lifetime indicating parameters. Different setups of recirculating P-type radiant tubes were investigated, including a reference case of an isolated tube. The investigations could be broadly classified into the study of the effects of different tube arrangements, burner operations (synchronous/asynchronous on/off firing), and changes of strip parameters (width/temperature). Results showed higher creep deformation of the central radiant tube in the setup with three tubes arranged horizontally in a row compared to three tubes stacked in a vertical column, even though the respective characteristic temperature values in a firing cycle were similar. Furthermore, the cases with asynchronous burner firing resulted in lower creep rates than other cases, where the burners were operating in synchronous on/off firing modes. In addition, the change of strip width had a higher impact on radiant tube lifetime compared to locally changing strip temperatures across the furnace. Alternating temperatures, caused by burner operation or process changes, such as change of strip’s speed or cross-section, and local temperature gradients were observed to be the main factors influencing the tube’s service life.

show abstract

Section: Early Macroscopic Studiessupporting

confidence: 66%

Influence of Surroundings on Radiant Tube Lifetime in Indirect-Fired Vertical Strip Annealing Furnaces

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Por ejemplo, los combustibles fó-siles más pesados, tienden a ser una fuente importante para la generación de hollín, lo cual puede ayudar a mejorar las propiedades radiantes de la llama, pero a disminuir la temperatura de esta. Entre los materiales utilizados para su construcción, se encuentran las aleaciones de alta resistencia como Ni-Cr y Fe-Cr-Al [7], sin embargo, debido a su alta emisividad, conductividad y buena estabilidad ante los choques térmicos [48], se sugiere el uso del Carburo de Silicio [11], [49]. Se pueden diferenciar dos grandes disposiciones geométricas y funcionales de los tubos radiantes [46]: de un sólo paso y de terminal simple.…”

Section: Tubos Radiantesunclassified

La radiación infrarroja como mecanismo de transferencia de calor de alta calidad en procesos de calentamiento

2012

View full text Add to dashboard Cite

En este artículo se pretende abordar la radiación infrarroja como un mecanismo principal de transferencia de calor de alta calidad en diferentes procesos de calentamiento, resaltar la pertenencia y problemática en el uso, la caracterización y el diseño de las tecnologías propias accionadas por sistemas de combustión. Para esto, se resume su fenomenología, sus definiciones, suposicionesy soluciones; se abordan algunos métodos numéricos utilizados para la solución de la ecuación de transferencia de radiación (Radiative TransferEquation (RTE)) y el acoplamiento de éstos a los códigos CFD (ComputationalFluids Dynamics); como también los tipos de equipos radiantes utilizados con mayor frecuencia, en especial los tubo radiantes; al igual que ciertas metodologíasexperimentales usadas para caracterizar los sistemas radiantes, y algunas metodologías de diseño. Se encontró, que el modelo del flux y el de transferencias discretas son pertinentes para darle solución al fenómeno con ayuda de los códigos CFD, como también, que el elemento de medición principalmente utilizado en las mediciones experimentales es el radiómetro; y que la metodología de diseño más práctica puede ser la optimización.

show abstract

“…In turn, this lowers the coefficient of expansion and causes material embrittlement leading to cracking tube breakage. Cracking tubes are exposed to high temperatures of up to approximately 1100 • C as they are used under such extreme conditions, and cracking coils are required to have high heat resistance and thermal efficiency [5]. In general, Ni-based heat-resistant steels are used to satisfy the high temperature strength and creep resistance of heat-resistant cracking tubes due to the strong catalytic action to form a filamentary coke (carbon deposition) on the inside surface of a cracking coil.…”

Section: Introductionmentioning

confidence: 99%

Effects of Pre- and Post-Carburizing Surface Modification on the Tribological and Adhesion Properties of Heat-Resistant KHR 45A Steel for Cracking Tubes

Amanov

Choi²,

Pyun

2021

Materials

View full text Add to dashboard Cite

In this study, the effects of ultrasonic nanocrystal surface modification (UNSM) technology on the tribological properties and scratch-induced adhesion behavior of a heat-resistant KHR 45A steel cracking tube, which is used for the pyrolysis process, were investigated. The main objective of this study is to investigate the effects of pre- and post-carburizing UNSM treatment on the tribological and adhesion performances of carburized domestic KHR 45A (A) steel and to compare the results with the existing carburized Kubota-made KHR 45A steel (B). A carburizing process was carried out on the polished and UNSM-treated KHR 45A steel substrates, which were cut out from the cracking tube, at 300 °C heat exposure for 300 h. The thickness of the carburizing layer was about 10 μm. UNSM technology was applied as pre- and post-carburizing surface treatment; both reduced the friction coefficient and wear rate compared to that of the carburized KHR 45A steel substrate. It was also found that the application of UNSM technology increased the critical load, which implies the improvement of adhesion behavior between the carburizing layer and the KHR steel substrate. The application of UNSM technology as pre- and post-carburizing surface treatment could help replace carburized Kubota-made KHR 45A steel (B) thanks to the improved tribological performance, enhanced scratch resistance, load bearing capacity, and adhesion of domestic KHR 45A (A) steel.

show abstract

Computational and experimental failure analysis of continuous-annealing furnace radiant tubes exposed to excessive temperature

Cited by 25 publications

References 6 publications

Influence of Surroundings on Radiant Tube Lifetime in Indirect-Fired Vertical Strip Annealing Furnaces

Influence of Surroundings on Radiant Tube Lifetime in Indirect-Fired Vertical Strip Annealing Furnaces

La radiación infrarroja como mecanismo de transferencia de calor de alta calidad en procesos de calentamiento

Effects of Pre- and Post-Carburizing Surface Modification on the Tribological and Adhesion Properties of Heat-Resistant KHR 45A Steel for Cracking Tubes

Contact Info

Product

Resources

About