Abstract
X-ray photographs were used to analyze auto-watering nozzles for structural defects. Defects were observed in 58% of the nozzles by a water pressure test, and in the majority of these, X-ray films showed that the combined length of the core section spring and packing (L) was greater than 1.81cm, and the spring (S) was Yshaped. Among those nozzles for which the water pressure test demonstrated no defects, (L) was less than 1.80cm and (S) was in the form of an isosceles triangle. Accordingly, it became evident that there is a close relationship between water leakage and defects in the internal strcuture and that it is possible to assess the quality of auto-watering nozzles by X-ray photography.