Balanced Cement Plug

Cement Placement technique

A balanced cement plug is a method of placing cement in either open hole or casing to act as a permanent barrier or kick-off plug. This method 'balances' the hydrostatic pressure inside the cement stinger and in the annulus by ensuring both cement and spacer columns inside and outside the stinger are at the same height. This allows the stinger to be pulled out of the wet cement, leaving a homogeneous cement of column of desired length across the open hole / casing.

It is common practice when placing the cement to under-displace slightly (a few barrels) to allow you to pull dry pipe and let the cement fall into place.