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Weir Diaphragm Valves - Flow Coefficients and Flow Factors

Typical flow coefficients - Cv - and flow factors - Kv - for weir diaphragm valves.

Typical flow coefficients - C_v - and flow factors - K_v - for weir diaphragm flanged cast iron valves of "Saunders" type:

Weir Diaphragm Valves - Flow Coefficients and Flow Factors
Valve Size		Unlined		Rubber Lined		Halar/Glass Lined		Plastic Lined
DN	Inches	C_v	K_v	C_v	K_v	C_v	K_v	C_v	K_v
15		6	5			6	5
20		12	10	9	8	12	10	7	6
25	1	18	15	14	12	18	16	11	10
32	1	28	24	22	19	28	24	17	14
40	1	43	37	35	30	45	39	31	27
50	2	80	69	64	55	88	76	59	51
65	2	127	109	102	88	132	114	83	72
80	3	185	159	148	128	186	160	148	128
100	4	315	272	252	217	336	290	270	233
125	5	420	362	363	313	440	379
150	6	605	522	484	417	630	543	505	435
200	8	1 300	1 121	1 309	1 128	1 320	1 138
225	9	1 630	1 405	1 320	1 138	1 680	1 448
250	10	1 980	1 707	2 000	1 724	2 100	1 810
300	12	2 550	2 198	2 600	2 241	2 700	2 328
350	14	3 700	3 190	3 750	3 233	3 880	3 345

Butterfly Valves - Flow Coefficients Cv
Typical flow coefficients - Cv - for butterfly valves.
Control Valves - Adding Flow Coefficients for Valves in Series or Parallel
How to add flow coefficients for control valves in series or parallel.
Control Valves - Cavitation
Control valves and cavitation, application ratio and multi stage control valves.
Control Valves - Flow Characteristics
Flow capacities vs. stem opening.
Control Valves for Water Flow – Kv Sizing & Pressure Drop Calculations
Control valve sizing and pressure drop calculations for water flow applications. Different valve types, Kv flow coefficients, and how to select the right valves.
Diaphragm Valves - Diaphragm Materials
Common diaphragm materials and their main properties when used in diaphragm valves.
Flow Coefficient Cv vs. Flow Factor Kv
Comparing flow coefficients Cv to flow factors Kv.
Liquid, Steam and Gas - Flow Coefficients Cv
Calculate flow coefficients for the design of control valves - Imperial units.
Straight Through Diaphragm Valves - Flow Coefficients
Flow coefficients - Cv - and flow factors - Kv - for straight through diaphragm valves.
Valve Selection Guide
Applications guide for selecting valves.