The area where the pad is to be affixed on the pipe and the inside surface of the wear pad must both be sanded first in order to create a rough surface for installation. Then an epoxy adhesive is generously applied to the inside surface of the wear pad. Make sure that the pipe surface is clean and free of all environmental debris and affix the wear pad to the pipe. Finally, add an additional amount of glue around the edges of the wear pad and apply temporary straps around the pipe and pad to tighten the contact between the pad and pipe while it is drying.
You can see instructions below:
Preparing the FRP pad for Installation