Ungula and ringfracture are due to higher surface hardness. The rational suggestions to settle fracture are put forward.
爪形和环形断裂由表面硬度偏高造成，并提出解决断裂问题的合理化建议。
2
Shangjing area is a volcanic dome formed by volcanic in active Early Cretaceous, in which the volcanic beds are dipping out with ringfracture and subvolcanic bodies intrusion in late stage.
上井地区是一个中生代早白垩世火山穹隆。火山岩岩层围斜外倾，环状断裂发育，晚期有潜火山岩侵位。
3
The fracture cause of a rolling ring of a rotary kiln was studied through a stress analysis and some improvements were proposed.