3300m长江定向钻穿越弹性敷设漂管施工

Pipe laying with elastic bending and pipe floating pulling method in a pipeline directional drilling construction in 3300m crossing the Yangtze River

水平定向钻穿越技术是目前管道铺设施工的一项重要施工工艺,在世界各国及各个行业得到广泛应用。由于穿越距离较长,作业带难以满足管道一次性预制需求,3 300 m长江定向钻穿越作业带可用部分只有1 km,要达到一次性预制存在巨大的拆迁量,而采用"二接一""三接一"等施工方法对长距离管道回拖存在较大风险,为了确保管道一次性回拖成功,采用弹性敷设、过路、过河等措施实现长距离管道一次性预制。通过对管道强度进行应力计算以及现场多次测量,最终采取管道弹性敷设漂管进美人港河的预制方案,实现了1 km管道陆地部分预制,2 km管道进入美人港河漂管的实施方案。实践证明,该措施大大降低了管道回拖力,减少了拆迁量,为管道的一次回拖成功奠定了基础,为今后的长距离定向钻穿越提供了重要参考。(图1,参6)

Horizontal directional drilling is an important construction technology for pipeline laying construction currently, which has been used widely in various industries all over the world. Because of the long crossing distance, the construction zone is hard to meet the one-time prefabrication demand of the pipeline. The usable part of 3 300 m directional drilling crossing construction zone of Yangtze River is only 1 km, and the amount of removal is huge to reach one-time prefabrication, and on the other hand, adopting the ＂double-jointing pipe＂ or ＂triplet-jointing pipe＂ construction methods would pose great risks to long distance backtow of pipeline. In order to ensure that the pipeline would be backtowed successfully in one time, it is important to adopt elastic laying, crossing road and crossing river measures for one-time prefabrication of long distance pipeline. After stress calculation of pipeline strength and multiple measurements on site, finally the prefabrication scheme of pipe laying with elastic bending and the pipe floating pulling crossing Meirengang River is adopted in the construction. The method in the land part prefabrication of 1 km pipeline and the implementation plan of 2 krn pipeline floating pulling in the Meirengang River are realized. Practice show that this measure reduces the pipeline backtow force significantly, decreases the removal, and lays a foundation for pipeline to backtow successfully in one time. This measure provides an important reference to the future directional drilling crossing over long distance.