1. How Do Rubber Duckbill Valves Work?

Rubber Duckbill Valves, widely used in the demanding applications of many industries, are precision-molded, one-piece elastomeric valves that provide reliable backflow prevention at low pressure differentials.  Rubber Duckbill valves allow free flow with positive differential pressure.  With negative differential pressure, backflow is checked.  Pressure drop across the valve is a feature unique to Rubber Duckbill valves. They can be designed to operate in a few millimeters (inches) of water to several hundred kPa (psi), depending on valve size, geometry and compound characteristics. Rubber Duckbill valves are also designed to start functioning at specific opening and closing pressure ranges, depending on your specifications.  Normally Open one-way check valves Prevents backflow leakage when minimal backpressure is applied Can be installed easily into hole and sealed by compressing flange

2. Rubber Duckbill Valves Features

 

 1. Reliable backflow prevention

 

 2. 100% elastomeric construction eliminates maintenance

 

 3. Will not corrode, warp or freeze open or shut

 

 4. 1”-2” Cracking Pressure, Low Head loss

 

 5. Curved Bill enhances sealing around debris

 

 6. Custom built for each application based on pressure and flow conditions

 

 7. Available in diameters from 1/2" (12mm) to 96” (2400mm)

 

3. Rubber Duckbill Valves Flange Type Data Sheet:

 

 1. DN150-350

 

SIZE I.D.(mm)	VALVE DIMENSIONS				Standard Dimensions for Retaining Ring Flange
	C(mm)	F/F(mm)	W(mm)	Weight(kg)	OD(mm)	C(mm)	id(mm)	Hole Diam. (mm)	Bolt Hole Num.	T(mm)	Weight(kg)
150	240	285	247	3.8	280	240	186	23	8	15	3.7
200	295	346	306	5.2	335	295	230	23	8	15	5.1
250	350	400	380	9.4	390	350	300	23	12	15	5.2
300	400	430	480	12.8	440	400	360	23	12	15	5.3
350	460	520	540	19.4	500	460	410	23	16	17	7.7

 

 

 2. DN400-2400

 

SIZE I.D.(mm)	VALVE DIMENSIONS				Standard Dimensions for Retaining Ring Flange
	C(mm)	F/F(mm)	W(mm)	Weight(kg)	OD(mm)	C(mm)	id(mm)	Hole Diam. (mm)	Bolt Hole Num.	T(mm)	Weight(kg)
400	515	550	605	20.6	565	515	460	25	16	17	10.4
450	565	605	645	25.5	615	565	514	25	20	17	10.5
500	620	630	750	35	670	620	564	25	20	17	13
600	725	760	880	56.2	780	725	668	30	20	17	15.1
700	840	775	950	70	895	840	772	30	24	20	22.6
800	920	860	1220	90	975	920	874	30	24	20	20.3
900	1020	940	1320	115	1075	1020	976	30	24	20	22.3
1000	1120	1150	1430	142	1175	1120	1078	30	28	20	23.8
1200	1340	1210	1620	272	1400	1340	1290	30	32	25	40
1400	1560	1270	1960	377	1620	1560	1500	34	36	25	51.3
1500	1660	1330	2060	410	1720	1660	1600	34	36	25	55
1600	1760	1409	2140	456	1820	1760	1700	34	40	30	69
1800	1970	1705	2700	580	2045	1970	1924	41	44	30	91.5
2000	2180	1850	2860	695	2265	2180	2110	42	48	32	112
2200	2390	2147	3500	770	2475	2390	2310	48	52	34	140.4
2400	2600	2604	3838	820	2685	2600	2536	48	56	36	144

Note: 
1.The rubber duckbill valve weight is approximate. 
2. Duckbill valve rubber flange bolt circles DN150-700 according to DIN PN10, DN800-2400 according to DIN PN6. Other standard available as ANSI Class150/300, BS-10, JIS 5K/10K. 
3.The retaining ring flange drilling is matched to rubber flange accordingly. 
4.Material of the retaining ring flanges usually is carbon steel, painted. SS304/316 available up on request. 
5. We can make rubber duckbill valves with any dimensions rubber flange available as per requirement. 
6. Duckbill valves of dimensions in the above table are available in inventory. Any other dimensions and designs available upon request.