Seals the annulus between the casing and the wellbore
Formation packer shoes and collars are added to casing strings that will be set in a vertical hole on top of a predrilled low-pressure formation. A mechanical packer element seals the annulus between the casing and the wellbore, allowing cement to be pumped into the annulus above the packer element.
Formation packer shoes and collars are available in two types: 852 series™ (poppet valve) and 855 series™ (flapper valve). The 855 series is supplied as a float shoe and can be converted to a collar when the float-shoe nose is removed.
The 852 series includes a double-poppet float valve that allows the casing to be floated in the hole. However, the 852 series does not allow automatic casing fill while casing is run in the hole.
The 855 series of formation packer shoes and collars includes a flapper-type float valve that allows casing to be floated in the hole. If desired, an orifice tube fill-up unit can be installed in the tool, allowing casing to be filled while it is run in the hole. A setting ball (used to set the packer element) and a latchdown plug and baffle are packaged with each tool assembly. The latchdown plug and baffle must be installed in the casing above the tool to ensure cement remains in place in the annulus after cementing operations.