Paper: MEASURED ROD STRINGTUBING WEAR AND ASSOCIATED SIDE LOADING

The Petroleum Industry has been aware of rod string and tubing wear ever since the first installation of steel sucker rods in production tubing. The associated rod string and tubing wear from this lift system continues to impact the ability of the Industry to economically produce oil and gas. The downstroke phenomenon of sucker rod string compression, buckling, sucker rod and tubing contact and associated sucker rod and tubing wear is becoming more clearly defined. (1,2,3) This paper will provide the Petroleum Industry with a more accurate understanding of sucker rod and tubing wear resulting from sucker rod side loading initiated by downstroke sucker rod buckling. This paper will present a description of test equipment and test parameters resulting in the following; 1. Calculated cycles to 100% tubing wall loss vs. side loading. 2. Calculated cycles to 100% sucker rod diameter loss vs. side loading. 3. Calculated cycles to 100% sinkerbar diameter loss vs. side loading. A better understanding of sucker rod and tubing wear will provide the Industry with better sucker rod string design guidelines. Use of these guidelines can reduce costly sucker rod and tubing wear and failures that impact the ability of the Petroleum Industry to economically produce oil and gas.