PURPOSE: To measure the worn-out amount of the right oven wall and the left oven wall of a carbonization chamber with high accuracy by a method wherein a criterion value which has been corrected according to the advance direction of a ram head is subtracted from a measured value.
CONSTITUTION: A plurality of sensors 1 are installed at equal intervals in the height direction at a ram head 2 for an extruder. The extruder is pushed into from the entrance part of a carbonization chamber, a distance up to an oven wall 6 is the measured by a correction sensor 8 at the junction part of the head 2 to a rod 3 and an initial measured value t1 is used as a criterion value in the width direction of the carbonization chamber. At the same time, measurements in the width direction are performed by the individual sensors 1, and individual measured values L1, L2, L3,... are obtained. Then the extruder is advanced, the rod 3 is moved by a distance between correction sensors 8, 9, and a distance t up to the oven wall 6 is measured by the sensor 9 in a state that the rod 3 has been deformed thermally. At this time, the criterion value t1 is regarded as having been changed by (t1-t2)=Δt. When the worn-out amount of the oven wall is found, it is corrected by Δt. When measured values by the individual sensors 1 at this time are designated as M1, M2, M3,..., worn- out amounts.of the oven wall are M1-t1+Δt, M2-t1+Δt, M3-t1+Δt,....
AIHARA TSUNEO
SUGIBE HIDETAKA
