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Aspects of the connection and restoration of polymeric pipelines for gas transport with the use of coupling and glue technologies based on heat-shrink couplings and glue compositions formed from epoxy polymers are analyzed. The effectiveness of epoxy glue compositions and the method for their ultrasonic modification is substantiated. It is noted that effective ultrasonic treatment makes it possible to enhance deformationstrength and adhesion characteristics of the polymeric composites obtained, which can be used for the repair and restoration of polymeric pipelines, and to reduce the level of residual stress in these pipelines, and lengthen their service life.Effective hardware components for the connection and repair of polyethylene (PE) pipelines using ultrasonic (US) modification and heat shrinkage are examined in a round of papers consisting of five parts.Among other things, characteristic features of the molding of epoxy repair couplings, which have a heat-shrinkage effect, are examined using low-frequency US-modification (Part 1), the effectiveness of production bases and equipment developed for repair of PE pipelines using US is investigated (Parts 2 and 3), characteristics of the connection of PE pipes with heat-shrinking epoxy-polymer (EP)-based couplings and with glass-cloth strips are brought to light (Part 4), and characteristics of the use of temperature-sensitive-resistor couplings for repair of PE pipes are analyzed (Part 5). The results presented are based on those of referenced investigations [1, 2] and on familiar technical solutions [3]. Problems of the Connection and Restoration of Polymeric Pipelines Used for Gas TransportIn addition to gas lines, polymeric, and, to wit, small-diameter (to 220 mm) PE gas lines are currently coming into ever-increasing use owing to their longevity (up to 50 years), and corrosion resistance.Restoration of damaged sections is one of the most important problems concerning pipeline operation [4]. Coupling and glue technologies, which offer a number of advantages over welding, are widely used for this purpose. Their implementation for polymeric, especially PE pipelines, is a complex technical problem [4].Thus, a number of pipelines, which have been assembled using polymeric glues, are operating successfully in Russia and other countries [5,6]. Analysis of the properties of familiar glues for the gluing of metals indicates that epoxy glue compositions (EGC) are being called upon all the more for these purposes [7,8].

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