1" Flange (Loose Ring), Spigot PVC Schedule 80 (856-010)

The 856-010 is a Schedule 80 PVC loose ring flange — commonly called a Van Stone flange — in 1" with a spigot end connection. This two-piece fitting consists of a PVC stub flange with a spigot end sized to the pipe's outside diameter, and a free-rotating Schedule 80 PVC backing ring that turns 360° around the stub neck. The spigot end inserts directly into the socket of an adjacent fitting or valve, joining via solvent cement to create a permanent, pressure-rated connection on the pipe side. The rotating ring then allows bolt holes to be aligned with the mating flange in any orientation without rotating the pipe, eliminating the frustration of fixed-flange bolt hole misalignment on pumps, valves, and equipment connections.

At 1", this is a compact flange well suited to instrumentation, chemical dosing, and smaller-diameter process and equipment connections. The spigot configuration makes it the right choice when the pipe side of the installation terminates at a fitting socket — if connecting directly to cut pipe ends, the slip socket version (854-010) is the appropriate selection.

Gray Schedule 80 PVC construction provides higher pressure ratings and thicker walls than Schedule 40, with strong resistance to acids, bases, and a broad range of industrial chemicals. The flat flange face conforms to ANSI/ASME B16.5 Class 150 bolt circle dimensions, ensuring compatibility with standard metallic and plastic mating flanges. All fitting dimensions conform to ASTM D2467.

Apply PVC primer and a Schedule 80-rated solvent cement to the spigot end before insertion. At the flange joint, use a full-face EPDM or PTFE gasket and torque bolts evenly in a cross pattern to ensure uniform seating without distorting the flange face.

Specifications:

Industries & Applications:

• Industrial Process Piping — Flanged connections to pumps, valves, strainers, and instrumentation on 1" Schedule 80 PVC process lines where rotating ring alignment simplifies bolt-up in confined equipment spaces
• Chemical Handling — Serviceable flanged joints on 1" acid, caustic, or solvent transfer lines where periodic disconnection for maintenance, chemical changeover, or equipment service is required
• Water & Wastewater Treatment — Chemical dosing injection points, metering pump connections, and instrument flanges on 1" PVC lines at treatment plants, lift stations, and filtration systems
• Pool & Spa / Aquatics — Flanged connections to 1" chemical feed equipment, automated dosing systems, and flow sensors on commercial aquatic facility equipment pads
• Agricultural & Irrigation — Flanged tie-ins to small pump systems, filter heads, and chemical injection equipment on 1" Schedule 80 PVC lines in agricultural water management applications
• OEM & Equipment Fabrication — Incorporated into PVC skid assemblies, chemical metering systems, and process equipment packages where compact 1" flanged connections are specified for field serviceability