CONSTANT FORCE CENTRALIZER
A constant force device has at least a first non-constant axial force driving the first set of arms and a second non-constant axial force driving the second set of arms, where the two sets of arms are offset from one another by 900. Each of the non-constant axial forces is converted to a radially extending force by the interaction of a force guide and actuator. The force guide is attached to the inner mandrel of the constant force device and is shaped to produce an essentially constant radially extending force through the entire range of motion of the arms. Typically each arm of the pair of arms has a pivoting arm and a telescoping arm where the joint between the pivoting arm and telescoping arm has one or more wheels to reduce friction as the constant force device moves through the tubular.