Patent ID: 7708064
Filing Date: 2010-05-04
Classification: E21B

Abstract:
1. A centralizer, comprising: a first stop collar configured to be affixed to an exterior surface of a pipe; a second stop collar spaced apart from the first stop collar and configured to be affixed to the exterior surface of the pipe; a plurality of circumferentially spaced apart longitudinal spacers each coupled at each longitudinal end to one of the stop collars; a first plurality of circumferentially spaced apart bow springs each coupled at one longitudinal end thereof to the first stop collar and at an opposite longitudinal end thereof to a first floating collar disposed between the first and second stop collars; and a second plurality of circumferentially spaced apart bow springs each coupled at one longitudinal end thereof to the second stop collar and at an opposite longitudinal end thereof to a second floating collar disposed between the first and second stop collars, wherein a shape of the first plurality of bow springs and the second plurality of bow springs is selected to cooperatively engage the longitudinal spacers and the floating collars such that when compressed the centralizer provides a substantially fluid-tight seal.