The technique of isolating a section of pipeline for repairs and additions without interruption of service can solve such as pressure reduce, removing the content inside the pipe,fire using and other problems.It can prevent the danger at work,improve safely index and repair can be finished quickly safely and saving money considerably at the same time.

The technique of isolating a section of pipeline for repairs and additions without interruption of service can be applied in spiral �Cwelded pipe,seamless pipe, straight slot pipe.The task can be done while the temperature in the pipe range from-20 ��to 80��,in special situation ranging from -20��to 200�� and the pressure in the pipe not more than 6.4Mpa can be kept.