Three are two kinds of
Circulating head: one kind for casing, the other kind for drill pipe, joint pin of casing circulating head is connected collar of casing, the drill pipe circulating head is connected with the drill pipe ' box thread, it is used to circulate mud before cementing. Type:
-simple type circulating head
-integral circulating head
-union circulating head
-Clamp type circulating head
-Drilling pipe circulating type
big union circulating head
-composed by its body, big union, casing joint
-its body is integral structure, bear high pressure
-It is alternative between casing head and cement head, convenient install.
Clamp type Circulation connector
-Composed by its body, clamp connector
-Clamp joint can be applied to different casing coupling, without being limited by the casing thread
-It is alternative between clamp connector and cement head, convenient install.
Drilling pipe circulating head
-The top is female screw of DP, the ends is male screw of casing.
-High quality alloy steel
-Integral structure, no weld, bear higher pressure
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