Galvanized steel pipe can not be welded connections. Because the pipe can not go to secondary galvanized, there is no way to do the inside weld corrosion treatment (except to enter people). Now starting from the design, usually greater than or equal DN100 pipe with clamp connections, less than DN100 can be used to connect the wire connection. If the design is not recommended to write the changes.

From the normative interpretation point of view, the purpose is to use galvanized pipe corrosion, galvanized pipe and welded connections so inherently contradictory.

From the actual situation, if the pipe is usually water at room temperature and is then filled with water, the inner weld corrosion usually not very serious. However, if no water or hot water, corrosion or not more serious first 150 sets of wire.

First set of filaments 150 can not. If it must be galvanized pipe buried, it would trench, pipeline and trench sites (especially the bolts) to strengthen the anti-corrosion, although the water supply and drainage and fire the acceptance of some description is not the same situation, but this can be considered a compromise approach the

Acceptance is so describe:

GB50242-2002. 9.2.3 pipeline flange interfaces, clasps, clamps, etc. should be installed in manholes or a trench, not buried in the soil

GB50261-96 Section 5.1.4A: buried pipeline connecting the pump room should adopt flexible couplings, grooved buried pipe joint bolts, nuts should be done preservative