MULTI BD Straight Flap Valves — MULTI BD Series

Protection against drainage & sewage backwater/flooding. Straight Flap Valve designed to be installed at the end of pipelines, either on vertical walls or directly onto the end of the pipe, to prevent backflow in sewage and drainage systems. Mounting Kit included: Stainless steel mechanical anchors are provided as standard for vertical mounting.

Multiple sizes from 100 - 200 mm


  • Body & Flap: Glass reinforced plastic using a isophtalic polyester resin
  • Seal: EPDM rubber
  • Mounting Kit: Stainless steel mechanical anchors

MULTI BD Straight Flap Valves MULTI BD Series


  • Integral foamed EPDM rubber gasket for direct fixing to a flange or headwall
  • Stainless steel mechanical anchors are provided as standard for vertical wall mounting
  • For flange ISO PN 10 use standard stainless steel bolts and nuts (not provided)

Reliable and Durable

High mechanical strength due to Glass Reinforced Plastic (GRP) construction. Design is verified by Finite Element Stress Analysis


Resistant up to 1 bar (10 m head) and back pressure to 1 bar (10 m head). Integral rubber seals easily replaced if damaged.


Fast and easy installation. Most sizes can be handled by one person. Very low operating pressure (cracking head) compared with metal flap valves.

Corrosion Resistant

Highly resistant to corrosion and UV Degradation. No coating needed.


Natural rubbers provide resistance to ozone, UV and mechanical compression.

Low Maintenance

Long service life and low maintenance.


Conforms to ISO 9001 quality standards.

  1. Reliable and Durable
  2. Watertight
  3. Lightweight
  4. Corrosion Resistant
  5. Resillient
  6. Low Maintenance
  7. Quality


A-PIPE OD B-PIPE OD C-DEPTH OF SOCKET MAX JOINT DEFLECTION ANGLE WEIGHT MAX Coupling OD Range min MAX Coupling OD Range max Larger Pipe ID min Larger Pipe ID max Smaller Pipe ID min Smaller Pipe ID max Sewer Main Wall Thickness Lateral Pipe min Lateral Pipe max Core Drilling min Sewer Main Core Break min Sewer Main Core Break max Foam Qty Required DIM. A DIM B DIM C DIM D DIM E DIM F Weight Pressure Resistance GG Part Part
212 mm220 mm50 mm110 mm55 mm195 mm0,50 kg1 bar (10 m head)MULTI-100-BD19041
252 mm250 mm55 mm125 mm66 mm230 mm0,70 kg1 bar (10 m head)MULTI-125-BD
252 mm285 mm55 mm160 mm66 mm260 mm1,10 kg1 bar (10 m head)MULTI-150-BD19061
372 mm340 mm70 mm200 mm75 mm315 mm1,60 kg1 bar (10 m head)MULTI-200-BD19081


GG PartPartDescriptionCase Qty.Case Wt.
MULTI-100-BD100 mm flange or headwall10,50 kg
MULTI-125-BD125 mm flange or headwall10,70 kg
MULTI-150-BD150 mm flange or headwall11,10 kg
MULTI-200-BD200 mm flange or headwall11,60 kg