This line of MARZOLF™ Two-Piece Backing Rings is designed to reinforce PVC and CPVC Van Stone flanges. These split flanges disperse bolt torque to facilitate higher bolt torques and ultimately increase the pressure capability of plastic flanges.

Size (in inches) Part No Inside Diameter I.D. Outside Diameter O.D. Thickness T. Bolt Circle B.C Holes H.D. No. Holes H.D. Dia
1” 357-3/8-TBD-SB *TBD 4-1/4” 3/8” 3-1/8” 4 5/8”
1-1/4” 358-3/8-TBD-SB *TBD 4-5/8” 3/8” 3-1/2” 4 5/8”
1-1/2” 359-3/8-TBD-SB *TBD 5” 3/8” 3-7/8” 4 5/8”
2” 268-3/8-TBD-SB *TBD 6” 3/8” 4-3/4” 4 3/4”
2-1/2” 182-3/8-TBD-SB *TBD 7” 3/8” 5-1/2” 4 3/4”
3” 172-3/8-TBD-SB *TBD 7-1/2” 3/8” 6” 4 3/4”
4” 149-3/8-TBD-SB *TBD 9” 3/8” 7-1/2” 8 3/4”
6” 126-3/8-TBD-SB *TBD 11” 3/8” 9-1/2” 8 7/8”
8” 144-3/8-TBD-SB *TBD 13-1/2” 3/8” 11-3/4” 8 7/8”
10” 150-3/8-TBD-SB *TBD 16” 3/8” 14-1/4” 12 1”
12” 152-3/8-TBD-SB *TBD 19” 3/8” 17” 12 1”