Backing Rings for Metallic Pipe
Two-piece backing rings install around existing stub ends and backing rings. No cutting the pipe, no re-welding. Sized for IPS, and angle rings.
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Interlocking Split Flanges
A Smarter Approach to
Pipe Installation & Repair
Get online faster and safer with Marzolf interlocking flanges. No cutting, no re-welding, no unnecessary downtime.
1955Established
Made in the USAWhatever the Job Demands
From New Construction to Critical Repairs
Whether you're bringing a new system online, performing scheduled maintenance, or responding to an unexpected failure, reducing downtime and improving worker safety are always priorities. Marzolf Interlocking Flanges help facilities complete work more efficiently and keep operations moving.
Made in the USA Since 1955
Engineered For The Demands of Fluid Processing
Since 1955, Marzolf has manufactured and supplied American-made interlocking split flanges for fluid processing facilities across North America. Our innovative two-piece designs eliminate cutting and rewelding, helping teams streamline new installations, simplify maintenance, and complete repairs with less downtime and risk.
No Cutting. No Rewelding.
Built for Faster, Safer Installations & Repairs
Marzolf interlocking flanges install after your stub ends or backing rings are already fused, welded, or glued in place, so you reassemble around the pipe instead of rebuilding it. Below: a look at the components that make it possible.
Two-Piece Rings for Use on Fiberglass Pipe
Two-Piece rings designed for use on fiberglass pipe. Backing Rings - reinforce molded fiberglass flanges. Stand Alone Rings - replace solid bolt rings.
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Two-Piece Backing Rings For Use On PVC, CPVC, PVDF Piping
Backing Rings - fit behind existing plastic rings and can be used on initial installation or existing assemblies to help prevent cracked flanges.
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Two-Piece Replacement Rings for Use on PVC, CPVC, PVDF Piping
Replacement Rings - Replace failed plastic rings quickly and permanently with no cutting or solvent rework and facilitate fast changeouts.
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Two-Piece Backing Rings to fit HDPE Flange Adapters
Interlocking split backing rings allow for ring installation after fusion. Available to fit IPS and DIPS flange adapters. Ask about FM Approved and AIS compliant rings.
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Compensation Rings - Spacer Plates - Filler Rings
Used when mating flat face flanges to raised face flanges to create a more bilateral flat face connection.
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Marzolf Benefits
Minimal Downtime
Faster repairs that reduce downtime, limit operational disruption, and help maintain productivity during critical events.
Lower Labor Cost
A two-piece design that simplifies installation, reduces labor demands, and helps teams complete repairs safely and efficiently.
Increased Safety
Less cutting and welding and less time spent in hazardous conditions, equate to a safer work environment, shorter exposures, and lower risk during critical repair activities.
Faster Installation
Engineered for strength and simplicity. Install and repair VanStone style pipe connections quickly and confidently, and get your equipment producing sooner.
Industries We Serve
Trusted by Fluid Processing Industries Nationwide
For seventy years, Marzolf flanges have helped plants, mills, and utilities across the country get back online faster, wherever fluids move through pipe.
Chemical & Fluid Processing
Corrosion-resistant backing rings and split flanges rated for aggressive chemical service and demanding process loops.
Water Utilities
Reliable, fast-install connections for treatment plants and distribution, built to keep process water moving.
Food & Beverage Processing
Stainless and thermoplastic options suited to washdown-heavy food and beverage environments.
Municipalities & Wastewater
Large-diameter HDPE and PVC solutions for lift stations, force mains, and collection-system repairs.
Power Generation
Rigid, high-integrity flange connections engineered to keep cooling and process systems in service.
Oil & Gas
Interlocking flanges built for the pressures and uptime demands of hydrocarbon handling.
Heritage
Seventy Years of Trusted Relationships
George B. Marzolf Sr. patented the original interlocking flange, and the company he founded in 1955 still builds them in River Falls, Wisconsin.
70+
Years in Business
1955
Founded in River Falls, WI
100%
Made in the USA
Patented & Proven
The original interlocking split flange, patented by our founder. Seven decades of real-world service in the toughest fluid-processing environments.
American-Made
Every flange is manufactured in our River Falls, Wisconsin facility from domestic materials. No overseas sourcing, no compromises.
Stocked & Ready
Interlocking flanges available from 1/2" to 30" to fit pipe, tube, polyethylene, fiberglass, PVC, and CPVC. Shipped when and where you need them.
Get In Touch With Us
Have a project or a concern you'd like to discuss? Call us. We'd love to talk with you.