Test and practice of submarine pipeline suspension treatment with local rock dumping method

For the suspension of submarine oil and gas pipeline in an operation area, a variety of treatment method wasadopted by the operator and failure occurred in different degrees. Based on the summary of pipeline suspension treatment athome and abroad, local rock dumping method was put forward for submarine pipeline suspension treatment. Definitely, themethod is to dump rock locally at the place where pipeline suspension occurs to form support and to divide the suspensionsection into two parts for the purpose of pipeline suspension treatment. For local rock dumping method, a pool test wasdesigned and through a series of pool tests, the damaging mechanism of flow to local rock pile was understood and theinstability flow speed for each designed rock pile was obtained, which provides test basis for practice of treating pipelinesuspension with local rock dumping method. Considering the limitation of pool test, the operator selected a submarinesuspension segment for practice with local rock dumping method and the reliability of local rock dumping was researched incombination with the pool test and the offshore rock dumping practice. The results show that the rock pile dumped locally is stable and reliable, and it can be used to treat the submarine pipeline suspension.