For the extended well, high angle drilling, horizontal drilling and deep well drilling, or in the well section of large dogleg severity, or the long open hole, casing wear often happens.

So, it is necessary to have a stabilized platform in the tool to obtain steady angle adjustable and independent to the rotation of drilling string.

Borehole curvature is one of significant index to evaluate Angle build-up capacity and wellbore quality, is very important to realize safety, speedily and efficiently drilling.