Here you will find two solutions to strengthen and eliminate cracking molded FRP flanges.
Lightweight backing rings designed to back-up and strengthen fiberglass reinforced pipe flanges. These rings fit behind molded fiberglass reinforced pipe flanges, effectively dispersing bolt stresses, to facilitate greater allowable bolt torques, and eliminate cracked FRP flanges.
Spacer Plates in this section are engineered to fit between fiberglass flanges and raised face flanges to preclude bending of the fiberglass flanges. Spacer Plates are available in a variety of materials; including coated carbon steel, polypropylene, and stainless steel.