Measured Rod Coupling On Tubing Wear
Scott W. Long, Flexbar Inc. & James V. Curfew, ARCO Permian
The Petroleum Industry is becoming more aware of the significance of rod string side loading and associated tubing wear. This wear is due to rod string buckling resulting from down-stroke compression and/or wellbore deviation. Rod string couplings are an integral part of rod string design. Proper selection and installation is critical since these couplings connect every design element in a rod string and can dictate well performance and economics. During lift operations, rod couplings can experience compression and side loading. The result is contact with the interior surface of production tubing and coupling on tubing wear. Results from this paper will provide the Petroleum Industry with a more accurate understanding of reciprocating rod coupling on tubing wear. This wear test utilized the following parameters: * 2-7/8", J-55, ERW tubing * 7/8" Spray metal and Class "T" rod couplings * Water/glycol fluid media * Side load of 57 lbs. A better understanding of rod coupling on tubing wear will provide the Industry with improved sucker rod string design guidelines. Use of these guidelines will reduce costly coupling on tubing wear and resultant failures that impact the ability of the Petroleum Industry to economically produce oil and gas.