Use of dsaw pipe in which cases

Use of dsaw pipe in following cases:
(1) For the high peak regulation of the pipeline, due to the user's gas consumption is very uneven, frequent fluctuations in pipeline pressure, steel pipe to withstand the large alternating stress, pipe defects have been extended under the alternating stress, if selection of welds, high probability of defects in the spiral welded steel pipe, pipe safety operations will not be guaranteed.

(2) Pipeline crossing the seismic fault zone or through the local high-intensity seismic area, due to the frequent geological activities of these lots, the pipeline will produce longitudinal or axial alternating stress. Spiral weld, the probability of defects is higher than that of dsaw pipe. Under long term stress, the probability of occurrence of spiral welded pipe is much higher than that of dsaw pipe. 

(3) Inside and outside the coating requires a high pipeline, should be used dsaw pipe. spiral pipe more welds are generally higher than the dsaw pipe, in the steel pipe inside and outside the anti-corrosion, anti-corrosion material and the combination of bare tube as a dsaw pipe close, anti-corrosion effect is not good.

(4) For important wear across the project, use of dsaw pipe. As the future maintenance and management is more difficult than the general line section, therefore, the use of excellent performance of dsaw pipe.

(5) For the weak links, such as hot simmer elbow pipe, should be used dsaw pipe. Hot simmer elbow due to the direction of change, its internal and external forces to bear the line than the general straight line to large, due to the process of simmering by the impact of various factors, the stress is not easy to eliminate, is the long-distance pipeline in the relatively weak links.