Wall Construction of the Lining Tube
Abrasion Layer
The abrasion layer is the inner layer of the composite with a defined thickness, which is intended as a sacrificial layer for the expected abrasion during operation. Accordingly, it must ensure operational safety with regard to physical and chemical resistance over the service life. Therefore, the average wall thickness of the composite (ec,m) is calculated from the design wall thickness plus the thickness of any abrasion layer.
The tests of the abrasion layer are carried out in accordance with Appendix A of DWA-A 143-3.
The abrasion layer consists of:
- a coating on the inside of the lining tube,
- a pure resin layer or
- a glass, felt or fleece-bonded resin-rich layer on the inside of the lining tube.
The wear of the abrasion layer must not impair the other functions of the lining tube, such as tightness and load-bearing capacity.