MULTITUBE VALVES / N ON-RETURN FLAP VALVES FOR THE DRAINAGE AND SEWERAGE BACKWATER PROTECTION PRODUCT ADVANTAGES • Light weight and compact design: fast and easy to install. • Highly resistant: pressure, corrosion, mechanical stress, UV. • Fixing: on vertical walls or on pipes. • Watertight: even for very low back pressures. • Innovative: designed in composite materials. PROTECTION AGAINST BACKWATER / FLOODING COUPLINGS & SEALS NON-RETURN & FLAP VALVES PENSTOCKS & REGULATO

MULTITUBE VALVES / N ON-RETURN FLAP VALVES FOR THE DRAINAGE AND SEWERAGE BACKWATER PROTECTION SCOPE For over 25 years, NORHAM has designed and manufactured MULTITUBE non-return flap valves. Our range in glass reinforced plastic using an isophtalic polyester resin is designed to prevent backflow in sewerage and drainage systems. Choosing as the main material GRP NORHAM offers an innovative, lightweight and highly , resistant MULTITUBE range (0,8 to 1 bar by model). For application in extreme environments (seafront type, pump discharge, etc.), please contact us. INSTALLATION •  Flap valves are...

MULTITUBE VALVES / N ON-RETURN FLAP VALVES FOR THE DRAINAGE AND SEWERAGE BACKWATER PROTECTION MULTITUBE MATERIALS MATERIALS Glass reinforced isophtalic polyester resin. Isophtalic Gel-coat. Low weight combined with strength, durability and corrosion resistance. EPDM EN 681-1 grade WC. Optional nitrile (NBR) seal available, consult us. Long term resistance to ozone, UV and mechanical compression. EN 10088-2 grade 1.4401 AISI 316 stainless steel. Ertacetal (POM) (in-line valves MULTI). Resistant to normal drainage and sewerage effluents and sea water. Self lubricating plastic. EN 10088-2 grade...

MULTITUBE VALVES / N ON-RETURN FLAP VALVES FOR THE DRAINAGE AND SEWERAGE BACKWATER PROTECTION FLAP VALVES MULTI-NB, FLAP VALVES DN 200 TO 600 TECHNICAL DATA •  Inclined flap (minimum 15°); •  flange ISO PN 10 (drilled on demand); •  back pressure: 1 bar (10 mWC, meter water column); •  eye-bolt in option, see below. INSTALLATION •  ntegral foamed EPDM rubber gasket for direct fixing to a flange or I headwall; •  tainless steel mechanical anchors are provided as standard for vertical s wall mounting; •  flange ISO PN 10 use standard stainless steel bolts and nuts for (not provided). *For ISO PN10...

MULTITUBE VALVES / N ON-RETURN FLAP VALVES FOR THE DRAINAGE AND SEWERAGE BACKWATER PROTECTION MULTI-NB, FLAP VALVES DN 800 TO 1500 TECHNICAL DATA •  Inclined flap (minimum 15°); •  lange ISO PN 10 (drilled on demand) for MULTI-NB 1000 (others f references, please consult us); •  back pressure: 1 bar (10 mWC); •  eye-bolt in option, see below. INSTALLATION •  tainless steel mechanical anchors are provided as standard for S vertical wall mounting; •  flange ISO PN 10 use standard stainless steel bolts and nuts (not for provided). *For ISO PN10 flange mountings, optional drilling to achieve, consult...

MULTITUBE VALVES / N ON-RETURN FLAP VALVES FOR THE DRAINAGE AND SEWERAGE BACKWATER PROTECTION MULTI-N, FLAP VALVE FOR DIRECT PIPE CONNECTION TECHNICAL DATA •  DN 200 to 600; •  or connection to any pipe (PVC, PEHD, fibre-cement, ductile iron, f clay, concrete, etc.); •  inclined flap (minimum 15°); •  back pressure: 1 bar (10 mWC); •  eye-bolt in option; •  delivered ready to install with NORHAM flexible coupling(1): EPDM and EN 10088-2 grade 1.4401 (AISI 304) stainless steel (grade 1.4401, AISI 316 in option). (1) The MULTI N flap valve is delivered with the appropriate flexible coupling (please...

MULTITUBE VALVES / N ON-RETURN FLAP VALVES FOR THE DRAINAGE AND SEWERAGE BACKWATER PROTECTION MULTI, IN-LINE FLAP VALVES A TECHNICAL DATA •  DN 250 to DN 500; •  in-line non return valve; •  or connection to any pipe (PVC, PEHD, fibre-cement, ductile iron, f clay, concrete, etc); •  back pressure: 0,9 bar (9 mWC); •  delivered ready to install with NORHAM flexible couplings(1); •  PDM and EN 10088-2 grade 1.4401 (AISI 304) stainless steel (grade E 1.4401, AISI 316 in option). (1) The MULTI flap valve is delivered with the appropriate flexible couplings (please confirm the pipe type and outside...

MULTITUBE VALVES / N ON-RETURN FLAP VALVES FOR THE DRAINAGE AND SEWERAGE BACKWATER PROTECTION TECHNICAL INFORMATION GRAPH 1: non-return valves, head loss Example: DN 250 non-return valve. Section = π x ز/4 = 0,05 m² Flow = 100 l/s = 0,10 m3/s Speed (m/s) = low (m3/s)/section (m²) = 0,10/0,05 = 2 m/s f Double flap Head-loss, non-return valve. Dynamic head loss is a loss of pressure in a pipeline due to friction from pipe walls or as liquids flows through elbows, valves and other fittings. The graph 1 shows head loss in full pipelines and compares different types of non-return valves. Ball type...