Cangzhou Spiral Steel Pipes Group Co., Ltd have 4 production lines of anticorrosion & thermal insulation to perform the 3LPE coating and FBE coating. The maximum outside diameter can be 2600mm.
The coatings are suitable for the protection of buried or submerged steel pipes at design temperatures of -40℃ to +80℃.
The present standard specifies requirements for coatings that are applied to spirally welded steel pipes and fittings used for the construction of pipelines for conveying liquids or gases.
Applying this standard ensures that the PE coating provides sufficient protection against the mechanical thermal and chemical loads occurring during operation, transport, storage and installation.
Extruded coatings comprise three layers: an epoxy resin primer, a PE adhesive and an extruded polyetlene outer layer. The epoxy resin primer is applied as a powder. The adhesive can be applied either as a powder or by extrusion. For extruded coatings a differentiation is made between sleeve extrusion and sheet extrusion. Sintered polyetlene coatings are single or multi-layer systems. The polyetlene powder is fused onto the pre-heated component until the desired coating thickness is reached.
The epoxy resin primer is to be applied in powder form. The minimum layer thickness is 60μm.
The PE adhesive can be applied in powder form or extruded. The minimum layer thickness is 140μm. the peel strength requirements vary depending on whether the adhesive was applied as a powder or was extruded.
The polyetlene coating is applied either by sintering or by sleeve or sheet extrusion. The coating is to be cooled after application to avoid unwanted deformation during transport. Depending on the nominal size, there are different minimum values for the normal total coating thickness. In the case of increased mechanical loads the minimu layer thickess shall be increased by 0.7mm. minimum layer thickness are given in table 3 below.