The machanical stage cementing collar  features inner-closing configuration,in which the circulating port is opened with free-fall or pumping-down plug.The closing plug drives the closing sleeve to shut the circulate port.

Features:
1, The machinery double stage cementer can be permanently self-locking in the closing position,with inner-closing structure.
2, The pressure-relief design prevents fluid trapping and compression between the opening device and the closing plug during the closing phase.
3, The I.D.of upper/lower sub is the same as that of casing,but smaller than that of closing sleeve,which can minimize chances of damages to the closing sleeve.
4, The inner seats which are made of the nitrile rubber/aluminum material and the anti-rotation structure are easily drillable.
5, With pumping-down plug,it is used in the operation of continuous cementing.
Property Parameters