The present nondestructive inspection techniques are unable to recognize small flaws, the metallurgical drawbacks and tight cracks, low temperature and high pressure proof-test can do it.
目前各种无损检测技术无法确定小裂纹、紧闭裂纹和冶金缺陷，压力验证试验却能弥补这方面的不足。
2
Discrepancy was found between some test results with equal pressure and higher pore water pressure based on Principle of Effective Stress and that by simulation of gravity of the tight sand.