US 10,502,007 B2 · Composite centralizer blade

Abstract

In accordance with embodiments of the present disclosure, a centralizer for aligning a tubular in a wellbore includes a stepped centralizer feature. The stepped centralizer feature includes a composite material with a stepped profile. That is, the stepped centralizer feature includes a first layer of the composite material having a convex rounded side for interfacing with the tubular, and a second layer of the composite material extending from the first layer. The first layer is wider than the second layer. The stepped centralizer feature may be a centralizer blade bonded to an outer surface of the tubular, or a stop collar used to hold a centralizer spring in place on the tubular. The stepped centralizer feature helps to distribute stress through the centralizer feature so that the centralizer feature does not crack or de-bond from the tubular in low temperature, high pressure environments.

Claims20

Dependent claims

A centralizer for aligning a tubular in a wellbore, comprising:

a stepped centralizer feature comprising a composite material shaped in a stepped profile, the stepped centralizer feature having a first layer of the composite material with a concave rounded side for interfacing with the tubular, and a second layer of the composite material extending from the first layer in a direction away from the concave rounded side, wherein the first layer is wider than the second layer, and wherein the composite material comprises a fiber reinforced ceramic, wherein the entire stepped centralizer feature is made from the fiber reinforced ceramic;
wherein the first layer of the composite material extends from the concave rounded side with an attack angle of between 15 and 30 degrees relative to the concave rounded side at two opposite edges of the first layer, wherein the attack angle of between 15 and 30 degrees reduces an amount of stress acting on the stepped centralizer feature at all connection points where the opposite edges of the first layer interface with the tubular to lower than a maximum principal stress on the stepped centralizer feature.

A centralizer sub for aligning a tubular in a wellbore, comprising:

a tubular portion comprising a connector for mating with a complementary connector of the tubular;
and
a centralizer blade comprising composite material bonded to an outer surface of the tubular portion, wherein the centralizer blade comprises a stepped profile having a first layer of the composite material extending from the outer surface of the tubular portion and a second layer of the composite material extending from the first layer to contact a surface of the wellbore or a casing in the wellbore, wherein the first layer is wider than the second layer, and wherein the composite material comprises a fiber reinforced ceramic, wherein the entire stepped centralizer feature is made from the fiber reinforced ceramic;
wherein the first layer of the composite material extends from the outer surface of the tubular portion with an attack angle of between 15 and 30 degrees relative to the tubular portion at two opposite edges of the first layer, wherein the attack angle of between 15 and 30 degrees reduces an amount of stress acting on the centralizer blade at all connection points where the opposite edges of the first layer interface with the tubular portion to lower than a maximum principal stress on the centralizer blade.

1 more element

Dependencies are inferred from the claim text.

Composite centralizer blade

Life of this patent

Composite centralizer blade

Life of this patent

Abstract

Claims20