Paper: CIRCUMFERENTIAL DISPLACEMENT PARTIAL HISTORY OF THE INDUSTRY PRACTICE

The oil & gas production industry has long used circumferential displacement (CD) for making up sucker rods. This is primarily to assure there is sufficient pre-stress "locked" in the threaded connection to prevent separation and allow the axial loads generated during pumping to be carried by the rod string without connection failures. The CD method also overcomes the problems with using only torque for makeup since torque has been proven to be an inaccurate makeup method mainly due to overcoming the various friction factors. These include: surface finish effects and lubrication effects. This paper provides a partial summary of the original tests conducted by Norris to establish the minimum recommended CD values along with additional testing programs conducted over the past forty years