Page 1

2-Way Spool Type Pressure Reducing Valve (DMO)

ISO 7368

NB 16 – NB 50

General Description

2-way pressure reducing valves are used to reduce a vari-

able input pressure (primary pressure at B) to a lower, con-

stant output pressure (secondary pressure at A).

The reduced pressure can be set using a pressure relief

valve on the valve cover. Depending on configuration, this

valve can also function as a pressure compensator.

The preferred mode of mounting is the manifold block

which, depending on the hydraulic circuit for the specific

application, can be equipped with several interconnected

valves.

The valves are available as “normally open” or “normally

closed” versions.

Benefits

• Maximum operating pressure: 350 bar

• Improved flow characteristics compared to series B

• Can be used with standard CCE covers series D and K

(RM or 1W)

• Available in multiple configurations

Sizes

• NB 16

• NB 25

• NB 32

• NB 40

• NB 50

2-Way Spool Type Pressure Reducing Valve Series D (06/2014)

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Operating Principle - Specification

Operating Principle

A DMO type pressure reducing valve is a spool

type valve without an effective surface in port B.

The effective surfaces in port C and in operational

port A are of equal size (surface ratio 1:1).

The flow direction is from B to A.

As port B is pressurized, oil will flow from B to A.

As the pressure in port A approaches the set

pressure value of the limiting valve, the spool will

move towards the closed position throttling the oil

flow. As the pressure in port A exceeds the set

pressure value, the spool will close port A and the

oil flow will be interrupted.

Depending on the hydraulic circuit and the adapta-

tion of suitable standard covers; a DMO type valve

can also be used, for example, in flow-control

functions as a pressure compensator.

Specification

* PU: Polyurethane; FKM: Fluorosilicone rubber (Viton

); NBR Nitrile rubber (Buna N); Other hydraulic fluids on request

General data Value Unit Specification

Mode of Construction - - 2-Way Spool Type Pressure Reducing Valve

Type - - DMO (Manual Pressure Adjustment)

Design - - Cartridge Valve

Mounting style - - Manifold Cartridge Mounting

Nominal size NB - 16 25 32 40 50

Mounting dimensions

according ISO 7368-...

- - BA-06-2-A

BB-08-2-A

BC-09-2-A

BD-10-2-A

BE-11-2-A

Mounting position

- Any

Flow Direction - - B  A

Operating pressure max. MPa 35

Ambient temperature

range

min. °C -30

max. °C +80

Seals* for

hydraulic fluids

- -

FKM+PU  M-DMO, hydraulic fluids on mineral oil basis

FKM  V-DMO, hydraulic fluids on mineral oil basis

HFD-hydraulic fluids

NBR  N-DMO, hydraulic fluids on mineral oil basis

HFC-hydraulic fluids

Hydraulic fluid

temperature range

- °C

-30 to +80 NBR

-10 to +80 FKM + PU

Viscosity range

min. mm²/s 2,8

max. mm²/s 380

Operating viscosity - mm²/s 15 to 45

Cleanliness

to ISO-Code

max. ISO 4406 (C) class 20/18/15

Cover

Pilot Valve DBD

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Basic Configuration Of A Pressure Reducer / Compensator

Basic Configuration

(1) Pressure reducing valve

(2) Pressure reducing valve

- Standard RM cover - Standard RM cover

- Pilot oil supply from cartridge port A - Pilot oil supply from cartridge port A

through cover port X through cover port X

- Without sandwich cover (max 3 bar spring) - With sandwich cover for 8 bar spring

- NB 16 to NB 40 - NB 16 to NB 40 (NB 50 with 3 bar spring)

(3) Pressure reducing valve (4) Pressure compensator valve (upon request)

- Standard 1W cover - Standard RM cover

- Pilot oil supply from cartridge port B - Pilot oil supply from cartridge port B

through 2-way flow controller through 2-way flow controller

- port Y connected to tank - port Y as pressure load tap downstream of the

- NB 16 to NB 50 throttle valve

- Higher flow rates possible compared - NB 16 to NB 40 (NB 50 with sandwich cover)

to configurations (1) and (2)

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Characteristic Curves Using 3 Bar And/Or 8 Bar Springs

Characteristic Curves

Conditions: system pressure 350 bar, oil temperature 40

C, oil viscosity 32 cSt

(Blue = performance limit with 3 bar spring, Red = performance limit with 8 bar spring)

NB25

NB40

NB32

NB50

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Characteristic Curves Using A Sandwich Plate Flow Control Valve

Characteristic Curves

Conditions: system pressure 350 bar, oil temperature 40

C, oil viscosity 32 cSt

(Red = performance limit with 0,5 bar spring)

NB25

NB40

NB32

NB50

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Dimensions

NB 16 NB 25 NB 32 NB 40 NB 50

H1 [mm] 82 87 92 106

166

)

H2 [mm] 35 40 45 60

120

)

H3 [mm] 23 22 26 39

)

H4 [mm] - - 27 30

)

H5 [mm] 47 52 57 72

182

)

B1 [mm]

85 102 125 140

B2 [mm] 65 85 102 125 140

L1 [mm] 9,5 13,5 16 20 20

L2 [mm] 9,5 13,5 16 20 20

L3 [mm] 7 23,5 32 43,5 51

L4 [mm] 16,25 26,25 34,65 46,25 53,75

L5 [mm] - - 3,5 4,5 4,5

Plugs MX - - G 1/8“ G 1/4“ G 1/4“

Mounting Screws

ISO 4762-12.9

M8x35 M12x40 M16x50 M20x70 M20x130

Tightening Torque [Nm] 30 100 300 550 550

Weight [kg] 2,9 3,9 5,5 9,6 20,7

Dimension B1 is larger than specified by ISO 7368

NB50 delivered standard with sandwich cover (H1=166 mm)

For NB50 with 0,5 bar spring subtract 60 mm from dimension given

Adjustment methods available

2: allen head screw with jam nut

8: method 2 + cap + seal

(pressure set and sealed)

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Options

Option: Sandwich cover for 8 bar spring NB16...NB40 (NB50 using max. 3 bar spring)

Option: 2-way flow control (NB06) using a sandwich plate (weight 1,25 kg)

NB 16 NB 25 NB 32 NB 40 NB 50

H1 [mm] 30 40 70 90 60

B1 [mm] 80 85 102 125 140

B2 [mm] 65 85 102 125 140

L1 [mm] 9,5 13,5 16 20 20

L2 [mm] 9,5 13,5 16 20 20

Weight [kg] 0,9 2 4,8 9,3 7,2

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Alternative Configurations

Alternative configurations for pilot valves that do not use port A.

It is recommended that pilot valves with no connection to port A be used in combination with

a sandwich plate (P connected to A).

Alternative:

DB pilot valve + sandwich cover +

RM cover

DBD

Standard:

AXXERON HYDROLUX DB pilot

valve + RM cover cover

AXXERON HYDROLUX

DBD

RM cover

Sandwich plate

RM cover

CKE CKE

Valve configurations using a flow control sandwich plate, regardless of pilot valve; do not re-

quire any special sandwich plates.

Option: Sandwich cover (NB06) with connections from P and A (weight 0,7 kg)

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Ordering Information

Order Example

2/2-Way pressure reducing valve, NB 32, manual pressure adjustment, normally open

M-DMOE32DL6MX2B/A10;P12

M: seal material

FKM + PU

L: spring 3 bar

M: function „normally

open“

2: adjustment method 2

Allen head screw with jam nut

B: spring pilot valve 0 - 70 bar

A10: orifice 1,0 in port A of the cover

P12: orifice 1,2 in port P of the cover

X: pilot oil supply

X and Y through mounting surface

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Order Numbers For Standard Configurations

Order Numbers

Pressure reducing valve with 3 or 8 bar spring (RM cover)

Function: normally open; Adjustment method 2, Spring pilot valve 350 bar, Seals PUR/FKM

Symbol Size Spring ZWD* Type code

3 bar - M-DMOE16D

6MX2K

8 bar × M-DMOE16D

6MX2K

3 bar - M-DMOE25D

6MX2K

8 bar × M-DMOE25D

6MX2K

3 bar - M-DMOE32D

6MX2K

8 bar × M-DMOE32D

6MX2K

3 bar - M-DMOE40D

6MX2K

8 bar × M-DMOE40D

6MX2K

3 bar × M-DMOE50D

6MX2K

8 bar - not available

*ZWD = sandwich cover required

Pressure reducing valve with sandwich cover flow control valve (1W cover)

Function: normally open; Adjustment method 2, Spring pilot valve 350 bar, Seals PUR/FKM

Symbol Size Spring ZWD* Type code

0,5 bar

- M-DMOE16D

6MX2K/MC_

0,5 bar

- M-DMOE25D

6MX2K/MC_

0,5 bar

- M-DMOE32D

6MX2K/MC_

0,5 bar

- M-DMOE40DR6MX2K/MC_

0,5 bar

- M-DMOE50D

6MX2K/MC_

* no sandwich cover required for these valve types

DM(K)O_D6-1-EN-Pressure Reducing-Compensator Valves - CDL66633-001-A-06-2014 DE

For more information contact us online.

office@axxeron-hydrolux.com