Blind Flange, PVC Schedule 80 3" (853-030)

The 3" PVC Schedule 80 Blind Flange is a solid, flat-faced thermoplastic flange with no pipe bore — designed to bolt directly onto the face of an open flanged connection to permanently or temporarily seal it. Unlike every other flange fitting in the Schedule 80 PVC line, the blind flange has no pipe connection on its back face. It is a blanking plate in flange form: bolted against a mating flange face with a full-face gasket to create a pressure-tight, leak-free termination at the end of a flanged piping run or at an unused outlet on a multi-port flanged assembly.

The blind flange serves three distinct roles in industrial PVC systems, each of which recurs throughout the service life of a flanged piping network. The first is permanent termination — closing the end of a flanged run at its designed endpoint, much like a pipe cap closes a slip or threaded run, but in a bolted flange format that is consistent with the flanged system it terminates. The second is temporary isolation — blanking off a flanged outlet, nozzle, or branch connection during system commissioning, phased construction, or equipment changeout, with the expectation that the blind flange will eventually be replaced by an active connection when the system is extended or the equipment is installed. The third, and perhaps most operationally significant, is pressure testing — a blind flange bolted to the end of a flanged run allows the upstream system to be hydrostatically pressurized and tested for joint integrity before the downstream connection is made or the system is placed into service.

What distinguishes the blind flange from a pipe cap or threaded plug in a flanged system is the mechanism of removal. A bolted blind flange can be unbolted and removed cleanly — without cutting pipe, without disturbing cemented joints, and without requiring specialized tools — at any point in the system's life. In industrial piping systems where flanged connections are standard precisely because future access and disassembly are anticipated, this removability is not incidental; it is the functional reason a flanged termination is specified over a cemented cap or threaded closure in the first place.

Drilled to ANSI B16.5 150 lb bolt pattern for compatibility with all standard ANSI 150 lb mating flanges across materials and manufacturers. Used with a full-face gasket, which is sold separately and should be selected for compatibility with the fluid service and operating temperature of the system. Manufactured to ASTM D2467 standards.

Specifications:

Industries & Applications:

• Pressure Testing & System Commissioning — The most operationally frequent application for a blind flange in industrial PVC systems; bolted to the end of a flanged run to allow hydrostatic pressure testing of the upstream assembly before downstream connections are made, equipment is installed, or the system is placed into service — providing a removable, pressure-rated termination that a cemented cap cannot offer at a flanged endpoint
• Chemical Processing & Handling — Used to blank off unused nozzles, outlets, and branch connections on chemical process equipment, reactor vessels, and storage tank flanged ports in chemical-resistant PVC systems where a bolted, removable closure is required at an inactive connection point
• Water & Wastewater Treatment — Applied at the terminal ends of flanged process mains, at unused equipment nozzles, and at temporary isolation points in treatment plant piping during phased construction, equipment installation, or system expansion — providing a pressure-rated removable termination consistent with the flanged system specification
• Pump & Equipment Isolation — Incorporated in pump station and mechanical system piping to blank off flanged connections during pump replacement, equipment changeout, or system modification — allowing the active portion of the system to remain in service while the isolated section is worked on
• Phased Construction & Future Connection Points — Specified at flanged stub-outs and future tie-in points on industrial piping systems where downstream equipment, processes, or system extensions are planned but not yet installed — providing a code-compliant, pressure-rated temporary termination that will be removed and replaced by an active flanged connection when the next phase is ready
• Industrial Manifolds & Multi-Port Assemblies — Used to blank off inactive outlets on flanged manifold assemblies, distribution headers, and multi-port valve stations where not all available flanged ports are in active service — maintaining system pressure integrity at each unused port without requiring a separate pipe run or welded closure