At present, plastic casing and MTC material are used for cementing in sandstone uranium mining. This paper discusses the particularity of plastic casing cementing. It is not effective to detect the quality of plastic casing cementing with the instruments that test the quality of steel casing cementing. Thus, a JMTC—1 logging tool using the principle of measuring ultrasonic damping parameters was developed. The instrument can be applied to the cementing quality detection for casings of various materials. This paper introduces the design principle of JMTC—1 logging tool and its application in plastic casing cementing quality detection.