Item Description
Essex Flange 1 1/2" BSP Mechanical Tank Boss — E2/SX
Genuine Essex Flange Solid DZR / Brass 1 1/2" BSP (~47.8mm OD)
The genuine Essex Flange E2/SX (1 1/2" BSP) is the industry-standard mechanical pipe connection engineered to create additional flow, return, or immersion outlets on closed hot water cylinders, header tanks, thermal stores, and cold water storage cisterns. Designed with an ingenious split interlocking design and guide wire mechanism, it installs entirely from the outside of the vessel, eliminating the need for hand access inside the tank or complex braze welding.
Identification & Technical Guide:
Brand: Essex Flange | MPN: E2/SX | Internal Reference: FTBE2SX | Thread / Size: 1 1/2" BSP Parallel Male Thread (47.8mm physical thread OD) | Hole Saw Size Required: 57mm (2 1/4") cut-out | Compatibility: Vented copper cylinders, unvented stainless tanks, thermal stores, galvanised tanks, and plastic/fibreglass cold water storage cisterns
Key Features
- External-Only Installation: Installs 100% from the outside of the vessel using the supplied insertion guide wire, making it ideal for closed cylinders and inaccessible tank corners.
- Robust DZR/Brass Construction: Machined from heavy-duty dezincification-resistant brass to withstand aggressive water chemistries, high thermal cycling, and continuous pressure.
- Dual Temperature-Resistant Gaskets: Supplied complete with heavy-duty EPDM/cork-compound compression washers engineered to maintain a permanent watertight seal against curved tank walls.
- High-Flow 1 1/2" Bore: Provides a full-bore 1 1/2" BSP (~47.8mm OD) connection, suitable for high-volume secondary circulation loops, boiler return feeds, commercial plant connections, or secondary immersion bosses.
Installation & Compatibility Notes
Aperture Cut-Out Size: Drill a clean, deburred 57mm (2 1/4") diameter hole in the side of the tank using a hole saw. Clear away all copper swarf and remove all cylinder insulation foam within a 100mm circle around the hole down to bare metal.
Fitting Advice: Thread the internal flange onto the guide wire, feed it through the hole into the vessel, and pull it back tight against the inner wall. Slide the washers and outer body over the wire. Tighten the brass backnut securely with an Essex Flange spanner or large adjustable wrench while keeping tension on the centre spindle. Do not overtighten on thin-gauge copper cylinders.
Associated Products & Sizing Matrix
- Sizing Options: SX/E1 (1/2" BSP / 20.9mm OD), SX/E2 (3/4" BSP / 26.4mm OD), SX/E3 (1" BSP / 33.2mm OD), SX/E4 (1 1/4" BSP / 41.9mm OD), E2/SX (1 1/2" BSP / 47.8mm OD), SX/E6 (2" BSP / 59.6mm OD), SX/E7 (2 1/4" BSP / 65.7mm OD Immersion Boss)
- Installation Tools: 57mm Bi-Metal Hole Saw, Essex Flange Spanner No. 4/5
- Replacement Washers: Essex Flange 1 1/2" replacement washer set
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