Based on the research of the formation mechanism and evolution rule of hydrate flow obstacle during deep-water gas well testing, a new method for the prevention of hydrate flow obstacle based on safety testing window is proposed by changing the previous idea of “preventing formation” to the idea of “allowing formation, preventing plugging”. The results show that the effective inner diameter of the testing tubing and the wellhead pressure decrease gradually with the formation and precipitation of hydrates during deep-water gas well testing, and it presents three typical processes of slow, fast and sudden changes. There is a safety testing window during deep-water gas well testing. The safety testing window of deep-water gas well testing decreases first and then increases with the increase of gas production rate, and increases with the increase of hydrate inhibitor concentrations. In the case with different testing production rates, a reasonable testing order with alternate low and high gas production rates has been proposed to further reduce the dosage of hydrate inhibitor and even avoid the use of hydrate inhibitors considering the decomposition and fall-off of hydrates. Compared with the traditional methods, the new method based on safety testing window can reduce the dosage of hydrate inhibitor by more than 50%.

在对深水气井测试过程中水合物流动障碍物形成机理和演化规律进行研究的基础上，通过改变以往的“预防地层”概念，提出了一种基于安全测试窗口的水合物流动障碍预防新方法。关于“允许形成，防止堵塞”的想法。结果表明，在深水气井测试中，测试管的有效内径和井口压力随着水合物的形成和沉淀而逐渐减小，并呈现出缓慢，快速和突然变化的三个典型过程。在深水气井测试中有一个安全测试窗口。深水气井测试的安全性测试窗口随产气量的增加先减小后增大，并且随着水合物抑制剂浓度的增加而增加。在不同的测试生产速率的情况下，已经提出了合理的测试顺序以及交替的低和高气体生产率，以进一步减少水合物抑制剂的用量，甚至考虑到水合物的分解和脱落，甚至避免使用水合物抑制剂。与传统方法相比，基于安全性测试窗口的新方法可将水合物抑制剂的用量减少50％以上。