一、事故实例 (1)某市煤炭公司从1980年3月30日起的一周内连续有四个YSP-15型钢瓶破裂,其中三个在用户使用过程中漏气,一个在灌装过程中泄漏,由于用户及时发现,及时转移,均未引起火灾。四个钢瓶中有两个是在焊接影响区破裂,另两个在瓶体上有长100毫米左右的脆性裂纹,钢瓶是1977年5月生产的,实际使用时间不足三年。 I. Examples of accidents (1) A city coal company broke four YSP-15 cylinders continuously during the week beginning March 30, 1980. Three of them leaked during the user’s use and one during the filling process. Leakage, as a result of timely detection and timely transfer by users, caused no fire. Two of the four cylinders were cracked in the weld affected zone, and the other two had brittle cracks on the cylinder body about 100 mm long. The cylinders were produced in May 1977 and had a practical life of less than three years.