drain pipe in rock stratum

anchored pipe-pipe

branch pipe welded directly to the run pipe

copper pipe and aluminum pipe

pipe and pipe-plate

Pipe in Pipe

pipe in pipe casing

pipe-in-pipe casing string

pipe-in-pipe systems

PVC pipe vinyl pipe

PVC pipe|vinyl pipe

vinyl pipe PVC pipe

welding part of copper pipe and low corbon steel pipe

assemblage of source-rock reserve and cap-rock

flexible rock and special flexible rock

from thick rock salt to thin rock salt

hard rock interbedded with soft rock

metamorphic rock of the original rock

rock and rock mass