MULTILAYER POLYMER ANTIRUST COAT WITH IMPROVED PROPERTIES

FIELD: process engineering. ^ SUBSTANCE: invention relates to coat and method of coating outer surfaces. Proposed method of coating pipeline outer surfaces by polymer capable of forming cross-links under action of water comprises the following stages: a) pipeline outer surface is coated by, at least, one polymer that forms cross-links under action of water. Note here that said polymer represents HDPE grafted by alkoxy silane. b) Polymer is cross linked on subjecting it to water at increased temperature to produce cross-linked polymer layer unless cross linking degree makes ëÑ30% to ëñ80%. c) Polymer is cross linked that can form cross links under action of water at ëÑ50C to ëñ350C, preferably at ëÑ150C to ëñ300C, more preferably at ëÑ200C to ëñ260C. Note here that during these stages, pipeline is heated to ëÑ170C to ëñ230C, preferably to ëÑ180C to ëñ220C, more preferably to ëÑ190C to ëñ210C. Powder ionic spraying method is used epoxy resin layer is applied with thickness of ëÑ0.08 to ëñ0.16 mm, preferably of ëÑ0.10 to ëñ0.13 mm, more preferably, 0.125 mm. Method of envelopment extrusion is used to apply a layer of glue with thickness of ëÑ0.15 mm to ëñ0.30 mm, preferable of ëÑ0.22 mm to ëñ0.27 mm, more preferably of 0.25 mm. By method of extrusion, applied is upper layer of HDPE with thickness of ëÑ2.8 mm to ëñ3.2 mm, preferably of ëÑ2.9 mm to ëñ3.1 mm, more preferably of 3 mm. Extrusion is used to apply layer of HDPE cross linked by silane with thickness of ëÑ0.8 mm to ëñ1.2 mm, preferably of ëÑ0.9 mm to ëñ1.1 mm, more preferably of 1 mm. Now, pipeline is treated by water with temperature of ëÑ10C to ëñ40C, preferably of ëÑ20C to ëñ30C, more preferably of 25C. Coat is made as described above. Invention covers also coated pipeline. ^ EFFECT: improved operating performances and expanded applications. ^ 11 cl, 2 tbl, 3 dwg, 2 ex Изобретение относится к покрытию и способу покрытия наружной поверхности. Способ покрытия наружных поверхностей трубопроводов полимером, способным образовывать поперечные связи под действием воды, включает стадии, на которых: ! a) покрывают наружную поверхность трубопровода, по меньшей мере, одним полимером, способным образовывать поперечные связи под действием воды, при этом применяемый полимер представляет собой привитой алкоксисиланом полиэтилен высокой плотности (ПЭВП), ! b) сшивают полимер, подвергая его действию воды при повышенной температуре в процессе формирования слоя сшитого полимера до тех пор, пока степень сшивания не до