Wall Construction of the Lining Tube
Total Wall Thickness
The (static) design thickness of the composite results from its total wall thickness (see picture) by subtracting the thicknesses of the:
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Internal membrane (foil/coating),
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External membrane (foil/coating),
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Pure resin layers,
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Abrasion layer,
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Reinforcements as installation aid.
The minimum wall thickness of the composite (ec,min) shall be at least 80 % of the design thickness (plus the thickness of any abrasion layer) or 3 mm, whichever is greater [ENISO 11296-4:2018].
1. External membrane / preliner (e2 = thickness of external membrane)
2. Outer pure resin layer / fleece layer
3. Composite (static load-bearing)
4. Abrasion layer
5. Internal membrane / coating (e1 = thickness of internal membrane)
6. Host pipe
ec = Thickness of the composite (pure resin layer / fleece layer (2) + composite (3) + abrasion layer (4))
etot = Total thickness (1 + 2 +3 + 4 + 5)