Application of retrievable tie-back device of system with rubber plug in remedial cementing with liner

In view of the complex conditions in running drill string and mandrel short circuit in liner hanger as well as fish in liner which plugs the liner and so normal circulation cannot be established during liner cementing, this paper has designed a retrievable tie-back device in a system with rubber plug for remedial cementing. Through the calculation method presented in this paper, the downward weight on this tie-back device can be obtained, so the tie-back device can be effectively sealed with the tieback barrel on liner hanger without hanging and unsetting. This tie-back device can be retrieved out directly after cementing job is finished, hence ensuring the safety of running drill strings. The application of the rubber plug system plays a role of effective isolation between cement slurry and drilling fluid and bumping pressure when enough volume of slurry is displaced, which improves the displacement efficiency of cement slurry and ensures the quality of liner remedial cementing.