Method for Calculation of Stroke Losses in Carbon Fiber Continuous Sucker Rods

Carbon fiber continuous sucker rods are used extensively,but there are no techniques currently available for calculations related to the stroke losses of such rods.Conventional methods deployed for stroke losses in steel rods are characterized by significant errors.In extreme cases,such errors may lead to downhole collisions.By analyzing the materials in the carbon fiber continuous sucker rods and taking into consideration the structural features,the as well as impacts of working temperatures over carbon fiber composite materials and relevant elastic modulus,an innovative model to calculate the stroke losses in carbon fiber continuous sucker rods was developed.The model took the impact of rod vibration into account.Calculation results showed errors in calculated stroke losses were reduced from 33.1% of the conventional method to the present level of 3.6%,which can effectively satisfy accuracy requirement related to calculating stroke losses.Research results indicated the innovative calculation model could effectively remove problems related to significant errors and inaccurate adjustment of stoke tolerances in stoke loss calculation in carbon fiber continuous sucker rods.