API Standard Spiral roller casing centralizer
There are two sets of rollers on the blades, and the coaxial line of rollers is perpendicular to the wellbore coaxial line. When the casings reach to inclined part, one hand the major part of casing will not contact with the lower side of wellbore, hence the friction area will be smaller. On the other hand, due to the rolling of roller, the conventional sliding friction will be changed to rolling friction, which greatly reduces the coefficient of friction resistance between casing and sidewall, and is conducive to put in the casing.
some specifications for reference:
 
  








Features
 
1. Spiral blades increase annular turbulence.
 
2.  With the shape of stream-lined, it enables casing run easily in wellbore.
 
3. Both straight blade and spiral blade are available.
 
4. The material can be cast steel or cast aluminum.