one aspect of the invention is the utilization of a compression arrangement as described herein in conjunction with the above mentioned wearbushings as described above casing hangers are run together with a wearbushing through the wellhead the wearbushings are disposed to be gripped by a grip mechanism of the invention to lock down the casing hanger during the various wellbore drilling related activities such as pressure testing the next drilling phase etc once the activity is complete the grip mechanism is then released in order to remove the wearbushing before the next casing hanger is installed with reference to fig6 8 the systems illustrated use a grip mechanism such as upper compression system 165 of fig4 to hold and lock each casing hanger through a wearbushing on which it is run the wearbushing stays in place until the next casing hole is drilled bop tests can be performed without having to pull the wearbushing and with drill pipe in the hole such a system eliminates many installation steps in prior art systems rendering the system of the invention not only cost effective to manufacture and implement but which reduces installation time improves safety and provides a much better tubing hanger seal design for maintenance free operation of the well throughout.