Quantitative Influence of Coke Oven Wall Irregularity on Pushing Force

Many of the coke oven batteries in Japan have been in operation for about 40 years. These coke ovens tend to become obsolete, resulting in a production impediment such as increase in pushing force. This paper proposed an experimental expression named as a resistive index that describes resistance received by a pushed coke cake being in contact with an uneven coke oven wall. The resistive index is calculated based on the shape of the deformed oven wall. Linear relationship between a resistive index and a pushing force was experimentally verified by using a simulated part of a coke oven. The resistive index was applied to actually working aged coke ovens. A newly-developed diagnosis apparatus equipped with a 3D profile measurement system was utilized to acquire irregularity data of high-temperature coke oven walls. Here, correlation between the resistive index and the force development during pushing was also clearly confirmed. From these results, it was concluded that the resistive index enables to quantitatively assess the harmfulness of damaged coke oven walls from the standpoint of a rise in pushing force. The resistive index is available for evaluating the needs and preferentiality of maintenance of damaged coke oven.