What are the common centralizers and how to select them?

A centralizer,also known as a centralizer,is a centralizer mounted on the outer surface of the casing to ensure that the running casing string is centered in the wellbore.The use of centralizers in oil and gas drilling and production improves the operating stability of the bit,thus extending the service life of the bit.Common centralizers mainly include rigid centralizers,integral centralizers,drum centralizers and hinged centralizers.
1.Integral centralizer

According to the material forming form,the integral centralizer can be divided into:pipe integral stamping type and coil stamping type.Pipe integral stamping type,that is,by cutting,wire saw,liquid cutting into circular steel pipe by pressing and other processes,without welding.Sheet rolling stamping type,is the whole steel plate through cutting,rolling,wire saw,welding and other processes,finally hydraulic forming,welding is allowed.

2.Rigid centralizer

Rigid centralizers can rotate and slide up and down the casing,or they can be fixed to a part of the casing with a set screw or a set ring.Rigid centralizers have obvious advantages over elastic centralizers.Rigid centralizers are a good choice if rotating casing is needed to improve displacement efficiency during vertical well cementing.In inclined and horizontal Wells,spring plate support centralizers can no longer support the heavy casing string.If you need to rotate the cement seal section of the casing,the rigid centralizer is selected.