Ключевые слова:
Plastics, Gas pipelines, Gaseous fuels, Polyethylene, Plastic pipelines, Pipelines, Pipework systems, Thermoplastic polymers, Pipe couplings, Pipe fittings, Gas-pipe fittings, Spigot-and-socket joints, Saddle joints, Butt joints, Welded fittings, Fusion welding, Electrical heating elements, Dimensions, Colour, Testing conditions