Page 1
CEE and REE 2-way cartridge valves for plug-
closed installation cavities
NG16 & NG25
Operation principle / applications
CEE and REE 2-way cartridge valves have two working ports
(A and B) and a pilot port X.
Pressure, directional and check functions are possible.
Depending on the function desired, flow through the valve can
be from either A to B or B to A.
The valves are leak free in port A due to the design of the
poppet valve seat. For a leak free port B, it is possible to fit
many of the poppet types with a shaft seal. This will separate
port B from the pilot port X.
CEE and REE 2-way cartridge valves are used primarily in
hydraulic manifolds in combination with other valves to create
application specific hydraulic circuits.
The valves are available in sizes 16 and 25.
Advantages
• Maximum operating pressure: 420 bar
• Streamlined design for optimized flow
• Space saving installation in manifolds, eliminating the need for bulky covers.
• No limit to possible manifold installation depths when combined with a recessed plug
(metric high pressure plug)
Performance
• Nominal flow at 3 bar ∆p (Directional valve, B poppet, flow direction from A to B, without
spring, valve fully opened):
- Size 16: 370 L/min
- Size 25: 540 L/min
Note: When selecting a valve size, care should be taken to ensure
that a maximum oil velocity of 30 m/s in the A port is not exceeded.
A
B
X
(02/2014) 2-way cartridge valves for plug-closed installation cavities
Page 2
General Technical Data Limit Units Comments
Valve type - - 2-way cartridge under plug
Type designation - - CEE or REE
Valve design - - Seated valve
Mounting type - - Manifold mounting
Size - - 16 25
Plug hex key size mm 19 24
Plug torque - Nm 370 (M38x1,5) 750 (M52x1,5)
Approximate weight - kg 0,55 1,3
Cavity - - see cavity dimensions on page 6 + 7
Preferred orientation - - any
Flow direction - -
A B (Directional function)
A B (Check function, B A is blocked)
A B (Pressure function)
Operating pressure max. bar 420
Ambient temperature
min. °C -30
max. °C +80
Seal material / hydraulic fluid
- - NBR* : Mineral oil, HFB and HFC hydraulic fluids
- - FKM** : Mineral oil and HFD hydraulic fluids
- - other hydraulic fluids on request
Hydraulic fluid temperature - °C
-30 to +80 for NBR seals
-20 to +80 for FKM-seals
Recommended viscosity
min. mm²/s 15
max. mm²/s 46
Permissible viscosity
min. mm²/s 2,8
max. mm²/s 380
Recommended cleanliness
for functional safety
ISO 4406 class 20/18/15
Recommended cleanliness
for longer service life
ISO 4406 class 17/14/11
MTTF
d
value; ISO13849-1 Years 150
* NBR : Nitrile rubber (Buna-N)
** FKM : Fluoroelastomer
This catalog is for users with technical knowledge. To ensure all necessary characteristics for function and safety of the system, the user has
to check the suitability of the products described herein. The products described herein are subject to change without notice. In case of
doubt, please contact AXXERON HYDROLUX.
For the most current information, visit www.axxeron-hydrolux.com
Technical data
Page 3
Cartridge configurations and symbols
Pressure functions
Directional functions
Check functions (see page 10 for further details)
More detailed information regarding the various poppet types and configurations
can be found in our “2-Way Slip-In Cartridge Valves” catalog.
Page 4
Performance curves
Size 16
BO/BX; CO/CX Poppets EO/EX; FO/FX Poppets
AO Poppet EO Poppet (Check function)
Note:
- All performance curves (except check function) were measured without a valve spring.
- Cartridges with AO poppets should only be used for pressure control functions. For a pressure relief function it
is important that the pressure in port X not greatly exceed the pressure in port A, otherwise damage to the
valve seat may occur.
- The flow value of 360 L/min is equivalent to a flow velocity of 30 m/s though the A port of an ISO 7368
standard installation cavity. This flow velocity should not be exceeded.
Page 5
Performance curves
Size 25
BO/BX,CO/CX Poppets EO/EX; FO/FX Poppets
AO Poppet EO Poppet (Check function)
Note:
- All performance curves (except check function) were measured without a valve spring.
- Cartridges with AO poppets should only be used for pressure control functions. For a pressure relief function it
is important that the pressure in port X not greatly exceed the pressure in port A, otherwise damage to the
valve seat may occur.
- The flow value of 900 L/min is equivalent to a flow velocity of 30 m/s though the A port of an ISO 7368
standard installation cavity. This flow velocity should not be exceeded.
Page 6
Installation dimensions
Size 16 (cavity W407)
*minimum recommended countersink
depth to ensure that the plug remains
flush with the manifold surface.
1)
1) For operating pressures over 350 bar
we recommend an additional flanging
radius of 1.2mm, a deviation from the
standard ISO 7368 cavity.
2) The X port is not needed for a REE
check function.
2
)
Clearance fit depth
Clearance fit depth
Page 7
Installation dimensions
Size 25 (cavity W408)
*minimum recommended countersink
depth to ensure that the plug remains
flush with the manifold surface.
1) For operating pressures over 350 bar
we recommend an additional flanging
radius of 1.2mm, a deviation from the
standard ISO 7368 cavity.
2) The X port is not needed for a REE
check function.
1)
2)
Clearance fit
depth
Clearance fit depth
Page 8
Ordering code & spring opening pressures
Ordering code
Spring opening pressures [bar]
Note: When using a cartridge with a shaft seal (BX, CX, EX or FX poppet), we recommend using the
strongest available spring to ensure a secure closing against the friction force of the shaft seal.
Page 9
1)
plug orifice should be ordered separately
Preferred cartridge types (NBR)
2)
Size Description Part number
16
N-CEE016K6AOU/AH
X731-016AOU-900N00
N-CEE016K6BOT/AH
X731-016BOT-900N00
N-CEE016K6BXU/AH
X731-016BXU-900N00
N-CEE016K6COT/AH
X731-016COT-900N00
N-CEE016K6CXU/AH
X731-016CXU-900N00
N-CEE016K6EOT/AH
X731-016EOT-900N00
N-CEE016K6EXU/AH
X731-016EXU-900N00
N-REE016K6EOR/AH
X731R016EOR-900N00
N-REE016K6EOU/AH
X731R016EOU-900N00
25
N-CEE025K6AOT/AH
X731-025AOT-900N00
N-CEE025K6BOT/AH
X731-025BOT-900N00
N-CEE025K6BXU/AH
X731-025BXU-900N00
N-CEE025K6COT/AH
X731-025COT-900N00
N-CEE025K6CXU/AH
X731-025CXU-900N00
N-CEE025K6EOT/AH
X731-025EOT-900N00
N-CEE025K6EXU/AH
X731-025EXU-900N00
N-REE025K6EOR/AH
X731R025EOR-900N00
N-REE025K6EOU/AH
X731R025EOU-900N00
2)
For valves with FKM seals, simply substitute the seal material code letter (N for NBR; V for FKM) in the appropriate part
number. For example: the NBR part number X731-025BXU-900N00 will be X731-025BXU-900V00 for FKM.
Seal kits for valves without shaft seals
Valve size
(seal position)
Description Part number
Size 16 (1-8)
N-CEE016 (NBR seal kit - complete)
X731-016_O_D900N00
V-CEE016 (FKM seal kit - complete)
X731-016_O_D900V00
Size 16 (1-4)
N-REE016 (NBR seal kit - check function)
X731R016_O_D900N00
V-REE016 (FKM seal kit - check function)
X731R016_O_D900V00
Size 25 (1-8)
N-CEE025 (NBR seal kit - complete)
X731-025_O_D900N00
V-CEE025 (FKM seal kit - complete)
X731-025_O_D900V00
Size 25 (1-4)
N-REE025 (NBR seal kit - check function)
X731R025_O_D900N00
V-REE025 (FKM seal kit - check function)
X731R025_O_D900V00
Seal kits for valves with shaft seals
Size 16 (1-9)
N-CEE016 (NBR seal kit - complete)
X731-016_X_D900N00
V-CEE016 (FKM seal kit - complete)
X731-016_X_D900V00
Size 25 (1-9)
N-CEE025 (NBR seal kit - complete)
X731-025_X_D900N00
V-CEE025 (FKM seal kit - complete)
X731-025_X_D900V00
CEE16/25 REE16/25
1
2
4
3
4
1
2
8
7
8
6
5
6
9
4
3
4
optional M6 orifice
1)
Preferred cartridge types and seal kits
Page 10
Information regarding check valves
There are two different options available when configuring a check valve under a plug:
A. The first option is to use a standard cartridge (CEE) with a B poppet, a spring (in this case a
“T” spring) and X port connection shown in the figure below (connection from B to X via a
separate flow path in the manifold).
Example: Size 25
B. The second option is to use a check valve cartridge (REE) with an E poppet and spring (in
this case a “T”). If necessary, a B poppet can also be used, but the flow performance would
be comprimised. The X port in this case is connected to B within the cavity itself using a
special plug design, eliminating the need for an addition connection within the manifold.
Example: Size 25
We recommend option A when configuring a check valve due to the increased flow
performance and reduced pressure losses. For further recommendations on how to
maximize valve performance, please consult our “2-Way Slip-In Cartridge Valves” catalog.
A
B
X
A
B
X
For more information
contact us online.
office@axxeron-hydrolux.com
www.axxeron-hydrolux.com
© 2025 AXXERON HYDROLUX. All rights reserved. Changes reserved
X731R-CEE-2 Way Cartridges plug mounted-EN
X731R-CEE-CDL66624-001-02_2014-EN
