Mill-Pro supplies a full range of PE100 Flange Assemblies. A flange assembly is a standard PE flange or full-face PE flange (pictured above), complete with a matching loose steel backing flange, sold as a single assembly. Our full face flange assemblies are proprietary Mill-Pro designs, these have been type tested as required in BS EN 12201, therefore they only sold as matching sets. 

Flange Assemblies are for connecting PE to PE or to other pipe materials via flanged joint. The flange size selection is a function of the PE pipes Inside Diameter (ID) and the nearest matching Flange DN of the Non PE fitting. When connecting PE pipes (≥ dn250) to another material (such as pump, valve or fittings), use a Full Face flange assembly and select the best fit based on the PE pipes SDR rating and the EN 1092 nominal flange DN based on the Table below.  If connecting PE to PE via a flange joint, use a standard flange assembly. See Flange Selection table below.

Flange Adaptors are available from 90mm OD (DN80) to 2000mm OD (DN1800) in pressure ratings from PN4 to PN25. Loose backing flanges comply to BSEN 1092-1 PN16 drilling and ring thickness as standard. However, other drillings, pressure ratings and dimensions, such as ANSI, JIS, AS/NZS to match other equipment can also be supplied.  Typical Loose backing flange materials are:

Fusion Bonded Epoxy (FBE) a Polymeric anti-corrosion (Barrier) coatings for buried applications. Mill-Pro's coatings are applied and tested in accordance with the UK Water Industry Standard WIS 4-52-01  WIS 4-52-01 

Stainless Steel for exposure in above ground, marine environments or submerged applications, click here for Stainless Steel grade recommendations depending on the application.  

Flange selection table select the best fit flange type for PE to DI or Steel flanges using the table below:

Note 1. Recommended Flange DN is the best fit for matching the pipes ID when connecting equipment such as: valves, fittings & pumps etc. Use a Full face Assembly if indicated in Orange or use a Standard Flange Assembly if indicated in Green.

Note 2. Recommended Flange DN for connecting PE pipe to PE pipe using a flange joint, use a Standard Flange Assembly.

Note 3: Full-face flange adaptor designs are proprietary. Each supplier has its own design. Hong Kong Drainage Services Department (DSD) Appendix 5A, Clause 5.10, specifies dimensional and testing requirements for flange adaptors, including the provision of Type Testing (TT) results for a suppliers design in accordance with BSEN 12201-3 Table 4: Hydrostatic strength test at 80º C for 1000 hours. The supply of such independent Type Tests is essential to demonstrate the supplier's Full Face design will perform leak-free long term. 

Note 4: Fusion Bonded Epoxy (FBE) coating on loose backing rings is not recommended for prolonged direct UV exposure, due to the chalking effect occurring over time when epoxies are exposed to UV. We recommend stainless steel loos backing flanges.

CONNECTING PE FLANGES TO DUCTILE IRON FLANGES IN SIZES ≥ DN200

In larger sizes (Flanges ≥ DN200 / PE ≥ dn250) the flange drilling patterns between standard PE and DI flanges no longer line up with the nominal bore of Ductile Iron (DI) or steel pipe sizes (see images above).  This is especially true of PE pipes ≤ SDR11, due to its significant wall thickness in larger diameters.  So a Full Face flange assembly (slim flange adaptor) must be used to make the connection.

Full Face flange adaptors are designed to align the internal bore of Polyethylene pipes, with the equivalent nominal size Ductile Iron valve or fitting at a flanged connection joint.  In smaller sizes, ≤ DN150 the internal diameters of PE and DI line up (within < 10%) of standard PE ISO 9624 flange adaptors, so Full Face are not required. Click on the illustrations below to understand why Full Face flange adaptors are required DN200 and above.