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Flexible Drainage Fittings
250mm (DN) Mission Commercial Non-Return Valve.
  • 250mm (DN) Mission Commercial Non-Return Valve.
  • 250mm (DN) Mission Commercial Non-Return Valve Dimensional Drawing.

250mm (DN) Mission Commercial Non-Return Valve

1 - 3 working days
1 - 3 working days
Large Item
£861.50 ex. VAT

Delivery from £15 1 - 3 working days

Carbon neutral delivery from JDP vehicles

Return within 30 days for a full refund

Product Details


Product Type:
 Non-Return Flap Valve
Model Type: Commercial Range
Nominal Diameter: 250mm
     Body & Flap - PVCu
     Seal - Ethylene Propylene Diene Monomer (EPDM) to BS EN 681-1
Approx. Weight: 14kg

This Mission commercial GRP one-way flap valve is designed for use within sewerage and drainage systems to eliminate the risk of flood damage by the backflow of sewage or flood water into properties through low level entries; such as low level drain gullies, toilets and washing machine outlets.

Note: will require Mission Rubber Standard Couplings and Bushes (sold separately) for installation dependent on size of pipework.

Product Features at a Glance:

  • Resistant to 1 bar (10m head) back pressure
  • Low weight for ease of installation yet with high mechanical strength
  • Resistant to all normal sewage effluents operating at normal temperatures (below 80° C) and not containing harmful industrial effluents.
  • Seals at a low level of back pressure
  • Easily connected to any type of pipe material by means of couplings (not included)
  • Low maintenance

Product Dimensions (see dimensional drawing product image for reference)

 DN   A   B   C   D   E   Weight 
 250mm   485mm   455mm   730mm   260mm   60mm   14kg 

Manufacturers Advice:

  • General Locations - Flap valves should be fixed so as to avoid the accumulation of debris around the invert which could prevent the valve operating correctly.
  • Tidal Locations - Turbulence of flow due to severe wave action will shorten the working life of a flap valve. Therefore it is recommended that careful consideration is given to the positioning of valves and they are installed within an outfall bay or otherwise protected from direct wave action by baffles.

Mission Flexible Drainage Fittings
Mission Rubber (UK) Ltd is part of the worldwide Mission Rubber group of companies who, over 50 years ago, invented the flexible rubber coupling for the sewerage, drainage and plumbing industries. Since then Mission has grown to become the world´s No 1 manufacturer of rubber flexible couplings with manufacturing plants in both America and Europe, and distributors worldwide.

Flexible rubber drainage fittings offer a perfect solution to joining pipes of various materials in drainage, sewerage and plumbing installations. They consist of a rubber body with stainless bands that enable them to compress down uniformly, onto different sizes and types of pipe, to form a reliable, airtight and watertight seal. It is a robust design that is aided, in some couplers, by a centre shear band which provides resistance against heavy earth loads and shear forces, helping to ensure pipe alignment with joint flexibility.

Flexible rubber fittings are ideal for joining plastic drainage pipes to other drainage materials such as clay, concrete, twinwall, stainless steel, cast iron and pitch fibre.

Key Features of Mission Fittings:

  • Unique “Lock In Place” Rubber Profile
    • Made from EPDM rubber
    • Ensures clamps and shear band are properly positioned
    • Remain firmly in place during transit, stocking or installation on site
    • Internal stepped sealing lines achieve a better sealing effect
    • Additional EPDM sealing material can be compressed through sealing lines - giving special advantage for sewer pipes with rough surfaces e.g. concrete pipes
  • TOX - TECHNOLOGY Clinching Process
    • No spot welding of clamps to the shear band- heat created during the welding process burns the stainless steel
    • Eliminates negative aspects associated with spot welding
    • Bond meets or exceeds all relevant tensile strength and shear requirements
    • Incorporated in the shear bands on all Mission couplings

Please Note: All images shown are used for illustration purposes only and may differ from the actual product supplied.

1 - 3 working days
Product Type:
Drainage fitting
Install Type:
Non-Return Valve