Technical data, 5 differential pressure regulators – KROHNE DK 46 I-DK 47 I EN User Manual

Page 30

TECHNICAL DATA

DK46I - DK47I

www.krohne.com

08/2008 • 4000360001 MA DK46I-47I-R01-en

6.5 Differential pressure regulators

Differential pressure regulators are used to provide constant flow rates in the case of variable
inlet or outlet pressures. Minimum pressure levels are necessary to operate the regulators (see
regulator characteristics).

Differential pressure regulators are not pressure reducing valves.

Inlet pressure regulators, type RE, NRE

The regulators keep the flow rate constant in the case of a variable inlet pressure and a constant
outlet pressure.

The flow rate is constant in the device in the case of a fluctuating inlet pressure greater than 7.3
psig (0.5 bar).

Outlet pressure regulator, type RA, NRA

The regulators keep the flow rate constant in the case of a constant inlet pressure and a variable
outlet pressure. There must be a pressure differential between the inlet and the outlet pressure
for the outlet pressure regulator to function. The inlet pressure p1 must always be greater than
the outlet pressure p2.

The flow rate is constant in the device in the case of a fluctuating outlet pressure of 0 ... 80 psig
(5.5 bar).

Regulator characteristics

Example - inlet pressure
regulator RE1000:

Current flow rate:

35 ft

/h (1000 l/h) air

Outlet pressure p2 constant:

14.7 psi (1.013 bar abs.)

Example - outlet pressure
regulator NRA 800

Current flow rate:

28.3 ft

/h (800 l/h) air

Inlet pressure constant:

87 psig (6 bar)

Inlet pressure regulators, type RE and

NRE

Outlet pressure regulators, type RA and

NRA

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