Abstract: A non-metallic pipeline cleaning pig for cleaning a variable diameter pipeline comprises an elongated cylindrical body, front and back cups coupled to the body, and a plurality of generally circular wiping discs coupled to the body between the cups. The wiping discs are disposed in pairs spaced apart from one another. Each disc has plurality of circumferentially spaced fingers respectively separated by a plurality of circumferentially spaced slots. Each finger has a peripheral surface of a given arc length. The number and configuration of the fingers and slots is chosen so that the sum of the arc lengths is approximately equal to the internal circumference of the smallest diameter pipe section encountered.An abrasive may be applied to the fingers to enhance the cleaning action. In addition, cleaning solvent may be jetted from behind the pig to the internal surface of the pipeline in front of the pig.