Page 48 - Bürkert

Characteristics of a proportional valve Advice for valve sizing

In continuous flow applications, the choice of an appropriate
K 1,0
V valve size is much more important than with on/off valves. The
K
Vs
0,9 optimum size should be selected such that the resulting flow in
0,8 the system is not unnecessarily reduced by the valve. However,
a sufficient part of the pressure drop should be taken across the
0,7 2871
valve even when it is fully opened.
0,6
0,5 Recommended value: ∆p > 25 % of total pressure
valve
0,4 drop within the system
0,3
Otherwise, the ideal, linear valve curve characteristic is changed.
0,2
If the differential pressure (difference between inlet and outlet
0,1 pressure) exceeds half the value of the nominal pressure, the
0,0 characteristics may change.
0 5 10 [V] For that reason take advantage of Bürkert competent engineer-
4 12 20 [mA]
0 10 20 [mA] ing services during the planning phase!

Ordering Chart

Nominal Max. differential Max. coil Item no.
Port connection Orifice Kv value pressure pressure current
[inch] [mm] [m³/h] Brass Stainless steel
[bar(ü)] [bar] [mA]
G 1/8 0.3 0.002 10 10 90 254 451 254 452
G 1/8 0.4 0.004 8 8 90 254 453 254 454

G 1/8 0.6 0.01 6 6 90 254 455 254 457

G 1/8 0.8 0.018 12 6 220 235 994 235 995
G 1/8 1.0 0.027 10 5 220 236 000 236 001

G 1/8 1.2 0.038 8 4 220 236 261 236 262

G 1/8 1.6 0.055 6 3 220 236 267 236 268
G 1/8 2.0 0.09 3 1.5 220 236 273 236 274

Accessories

Description Item no.
Type 2871
Control electronics Type 8605, DIN-Rail version 178 362

Type 2507
Cable plug 423 845

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