(ECIC-39)Coke pushing force monitoring and transmission to the coke cake

摘要

It is well known that uncontrolled pushing force can lead to severe degradation of coke oven walls.The pushing force can easily be measured by a torque sensor on the driving shaft of the pushing machine. Thetorque sensor is generally based on strain gauges which measure micro-deformations of the driving shaft.The pushing curve shows a typical first peak which corresponds to the end of the coke cake compression step andthe beginning of the coke cake movement. Generally after this peak the pushing force rapidly decreases as:- coke starts to move (dynamic friction coefficient is inferior to static friction coefficient),- coke weight decreases,- and oven taper prevents from wall friction.The first peak generally corresponds to the highest stress applied on coke during the pushing process. Its intensityis related to the coke cake properties so to the coal blend composition and to coking parameters.Recorded pushing curves sometimes show a progressive increase of pushing force or further peaks during pushing.These peaks should be mostly attributed to the pushing machine and to the general condition of the oven.From the investigation carried out in this study, it can be assumed that the safe limit of pushing force first peak isaround 1.5 times the coke weight to push.