Protected Liner Hanger for stage cementing PHZSC is applied for RIH, hanging and liner
sealing in with two stage cementing. The hanger is used together with MMC1 sleeve or
PGMC packer.
When using the device like PHZSC the following technological operations are performed:
• RHI of the device as a part of a transport string liner;
• performing of the 1st stage of continuous or collar cementing with the cementing plug
running after the injection of the cement slurry for its separation from the displacement
fluid;
• matching of the top cementing plug with the lower hollow cementing plug installed in
the hanger;
• displacing the cement slurry to the outer annular space of the liner, removal of protection
from the early actuation when passing the cementing plugs through the collar, receiving
of the 1st stage “bump” signal and closing of the cementing ports;
• opening of the cementing ports by internal overpressure build-up at the depth of collar
installation up to the opening pressure of cementing ports;
• flushing of the first stage cement slurry above the collar cementing ports;
• performing of the 2nd stage of liner cementing with the cementing plug running after
the injection of the cement slurry for its separation from the displacement fluid;
• matching of the top cementing plug with the top hollow cementing plug installed in
the hanger;
• displacing the cement slurry to the outer annular space of the liner, receiving of the
2nd stage “bump” signal and closing of the cementing ports;
• checking the collar ports closing by pressure relief to zero;
• internal overpressure build-up and consequential actuation of PHZSC hanger units –
anchor, packers and liner disconnect – from the transport string;
• washover and pulling out of the transport string.
• drilling out of the cementing plugs and MMC collar seat after the end of WOC.