An ultrasonic inspection method includes exciting a first set of transducers in an array to introduce ultrasonic energy into a component, generating a number of echo signals using a second set of transducers in the array as receive elements, and processing the echo signals. With the charging method and apparatus, when charging the raw material and the carbonaceous material onto the moving hearth of the moving hearth furnace, the carbonaceous material is first charged onto the moving hearth to form a carbonaceous material layer thereon. Each of the channels includes a photon conversion channel element which is operable to convert photons to electric pulses.