RETRIEVABLE WATER SHUTOFF STRING WITH MINOR DIAMETER

A water shutoff string with only 95mm in diameter has been developed to resolve the problems,which Henan Oilfield is facing at present,of increasing damaged cased wells in which some downhole treatment operations could be not carried out.After the string was put into the test in the fields,the results of 11 tests show that this technology may be used effectively for separate layer water control in casing deformation wells and repaired casing wells with 97 to 139mm of inner diameters.In addition,it can be utilized for water shutoff and production in continuous perforated interval in a inter-zone.This paper mainly describes the structure,the working principle,the features and the field’s results of the water shutoff string.