Cement placement in a wellbore with loss circulation zone

A wellbore assembly comprising:

• a work string configured to be disposed within a wellbore comprising a casing and an open hole section extending between the casing and a downhole end of the wellbore, the wellbore comprising a loss circulation zone at the open hole section of the wellbore;
• and
• a liner assembly releasably coupled to a downhole end of the work string, the liner assembly comprising:
• a polished bore receptacle,
• a liner hanger attached to a downhole end of the polished bore receptacle, the liner hanger fluidically coupled to the work string and comprising a packer configured to be set on the casing by fluidic pressure from the work string,
• a liner, and
• a cementing sub attached to and disposed between the liner hanger and the liner, the cementing sub comprising an annulus packer configured to be set on a wall of the wellbore uphole of the loss circulation zone, the cementing sub comprising an internal mandrel movable in a direction parallel to a length of the cementing sub to activate the packer and to expose or cover a fluid port of the cementing sub such that, when exposed, the fluid port fluidically couples a bore of the cementing sub with a casing annulus defined between an external surface of the cementing sub and the wall of the wellbore, the casing annulus extending uphole from the annulus packer.

A cementing assembly comprising:

• an activation sub fluidically coupled to a work string configured to be disposed within a wellbore that comprises a casing and an open hole section extending between the casing and a downhole end of the wellbore, the wellbore comprising a loss circulation zone at the open hole section of the wellbore;
• and
• a liner assembly releasably coupled to the activation sub, the liner assembly comprising:
• a liner hanger fluidically coupled to the activation sub and comprising a packer configured to be set on the casing by fluidic pressure from the work string,
• a liner, and
• a cementing sub attached to and disposed between the liner hanger and the liner, the cementing sub comprising an annulus packer, the cementing sub configured to set, under string weight applied by the work string, the annulus packer on a wall of the wellbore uphole of the loss circulation zone, to allow cementing of a casing annulus defined between an external surface of the cementing sub and the wall of the wellbore, the casing annulus extending uphole from the annulus packer.