A six-bar linkage mechanism for conforming to the configuration of a tractored
surface having a central link defined by a tool body and a saddle link spaced from
the central link and movable for conforming with the tractored surface. A pair
of front links each having pivotal connection with respective ends of the saddle
link and having linearly movable pivotal connection with the central link to permit
angular and spacing changes of the saddle link relative to the central link. A
pair of centralizer links are located between the front links and have pivotal
connections with the saddle link and pivotal connections with the central link.
One of the pivotal connections is linearly movable on the central link. For tractor
tools, when the tractored surface is a wellbore or well pipe, a plurality of six-bar
linkages radiate from a tool body for surface conforming traction with the tractored surface.
