Bosch Rexroth SB23 User manual

Repair instructions
RE 66133-10-R/05.2013
Replaces:
66130-10-R
66130-11-R
66132-10-R
66132-11-R
66134-10-R
English
Control valves SB23, SB33
Hitch control valves EHR23,
EHR33
Control block assembly

The data specified below only serve to describe
the product. Any information with regard to
use only refers to application examples and
recommendations. Data available in catalogs
are no guaranteed characteristics. The
information given does not exempt the user
from making own evaluations and tests. Our
products are subject to a natural process of
wear and aging.
© This document, as well as the data,
specifications and other information set forth in
it, are the exclusive property of Bosch Rexroth
AG. It may not be reproduced or given to third
parties without its consent.
The cover shows an example configuration. The
product supplied may therefore differ from the
photo shown.
The original repair instructions were prepared
inGerman.

RE 66133-10-R/05.2013, SB23, SB33, EHR23, EHR33, Bosch Rexroth AG
3/16Contents
Contents
1 About this documentation 4
1.1 Validity of the documentation 4
1.2 Required and supplementary documentation 4
2 Safety instructions 5
3 General repair instructions 5
4 About this product 5
5 Assembly description 6
5.1 General instructions for the assembly 6
5.2 Control block disassembly 6
5.3 Control block assembly 8
5.3.1 Subplate assembly 9
5.3.2 Control valve and hitch control valve assembly 9
5.3.3 End plate assembly 10
5.4 Flange surface sealing element repair 11
5.4.1 Sealing elements for LS control blocks 11
5.5 Shuttle valve repair 13
5.6 Coupling flange seals repair 14

4/16 About this documentation
Bosch Rexroth AG, SB23, SB33, EHR23, EHR33, RE 66133-10-R/05.2013
1 About this documentation
1.1 Validity of the documentation
These repair instructions apply to the following products:
•Control valves SB23-M, SB23-EHS, SB23-EHS1, SB33-EHS1, SB33-EHS2
•Hitch control valves EHR23-EM2, EHR33-EHS1, EHR33-EHS2
▶ Read this documentation completely and in particular chapter 2 “Safety
instructions” and chapter 3 “General instructions on damage to equipment and
the product” in the basic documentation, before working with the product.
1.2 Required and supplementary documentation
▶ Only start works at the product when you have been provided with the
documentation marked with the book symbol and you have understood and
observed it.
Table 1: Required and supplementary documentation
Title Document number Document type
Control block SB23, SB33
Contains the necessary basic information for assembly and repair
66133-01-R Repair instructions
Related documentation is available in the instructions specified above and also
from www.boschrexroth.com/mobile-hydraulics-catalog, if necessary.

Safety instructions 5/16
RE 66133-10-R/05.2013, SB23, SB33, EHR23, EHR33, Bosch Rexroth AG
2 Safety instructions
Please observe all safety instructions of the basic documentation 66133-01-R at all
times.
3 General repair instructions
General repair instructions are contained in the basic documentation 66133-01-R.
4 About this product
Information on the identification and product description is contained in the basic
documentation 66133-01-R.

6/16 Assembly description
Bosch Rexroth AG, SB23, SB33, EHR23, EHR33, RE 66133-10-R/05.2013
5 Assembly description
5.1 General instructions for the assembly
Generally valid instructions are contained in the basic documentation 66133-01-R.
Disassembly and assembly is described using a control block with dummy block
segments with three tie rods.
The procedure for valves with five tie rods are the same.
Table 2: Dummy overview
Subplate
-KP, -VP
EHR valve
-EM2, -EHS1, -EHS2
SB valve
-M, -EHS1, -EHS2
End plate
-LS, -EHS
5.2 Control block disassembly
•Torque wrench with socket SW13mm
▶ Disassemble the control block according to the vehicle manufacturer’s instruction
and put it down on a clean and stable surface.
▶ Pull the electric plug-in connections.
▶ Separately numerate the control block segments.
1. Loosen the nuts at the tie rods , and by turning them counterclockwise
and screw them off.
Similarly, for valves with five tie rods the nuts to .
2. Pull off the end plate via the tie rods.
Tool
Preparation
End plate disassembly

Assembly description 7/16
RE 66133-10-R/05.2013, SB23, SB33, EHR23, EHR33, Bosch Rexroth AG
Fig. 1: End plate disassembly
1. Remove spacers that might be available from the tie rod screws.
The spacers are only used in case of repair. See also chapter5.3.2 on page9.
2. Pull off the control block segments via the tie rods.
Fig. 2: Control block segment disassembly
1. Loosen the tie rods , and by turning them counterclockwise and screw
them out of the subplate.
Similarly, for valves with five tie rods the tie rods to .
Fig. 3: Subplate disassembly
Control block segment
disassembly
Subplate disassembly

8/16 Assembly description
Bosch Rexroth AG, SB23, SB33, EHR23, EHR33, RE 66133-10-R/05.2013
5.3 Control block assembly
•Torque wrench for 30 Nm with socket SW13mm
For control blocks in EHS version with continuous pilot oil bores Rx and R,
control block segments are needed with O-ring counterbore for the pilot oil
bores.
The O-ring counterbores are designed with different diameters of the respective
following block segment.
For certain block combinations there are versions with O-ring counterbores
without continuous pilot oil bores.
If the control block segment flange surface shows punching marks which have
been processed by means of a whetstone, a spacer must be threaded on the
tie rod screws , and (or to ). (In case of an Open Center control
block the spacer is threaded only on tie rod .)
Tool

Assembly description 9/16
RE 66133-10-R/05.2013, SB23, SB33, EHR23, EHR33, Bosch Rexroth AG
5.3.1 Subplate assembly
1. Only use original M8 tie rods by Rexroth (property class 10.9).
2. Screw in the tie rod screws to (or to ) manually to the ground by
rotating them clockwise.
3. Assemble the sealing elements according to chapter 5.4.
4. If necessary, install spacers on the tie rods.
Fig. 4: Subplate assembly
5.3.2 Control valve and hitch control valve assembly
Ideal is the first position after the subplate.
A maximum of three SB valves should be flanged between the Yport of the subplate
and the EHR valve.
1. Assemble the shuttle valve according to chapter 5.5.
2. Assemble the sealing elements according to chapter 5.4.
3. If necessary, install spacers on the tie rods.
4. Push the EHR valve over the tie rods according to the specified order, with the
opposite flange O-ring side pointing at the subplate.
Fig. 5: EHR valve assembly
EHR hitch control valve
assembly

10/16 Assembly description
Bosch Rexroth AG, SB23, SB33, EHR23, EHR33, RE 66133-10-R/05.2013
1. Assemble the shuttle valve according to chapter 5.5.
2. Assemble the sealing elements according to chapter 5.4.
3. If necessary, install spacers on the tie rods.
4. Push the SB valves over the tie rods according to the specified order, with the
opposite flange O-ring side pointing at the subplate.
Fig. 6: SB valve assembly
5.3.3 End plate assembly
1. Push the end plate over the tie rods to the stop with the flange surface pointing
at the control block.
2. Screw the nuts without washers and/or locking washers onto the tie rod screws
manually by turning them clockwise.
3. Align the control block segments so that they face each other.
4. Preload the nuts with a torque of 5+1 Nm.
5. Tighten the nuts applying a torque wrench by turning the clockwise.
Tightening order ( with five tie rods, see Fig. 9).
Tightening torque MA= 25.5+2.5 Nm.
Fig. 7: End plate assembly
SB valve assembly

Assembly description 11/16
RE 66133-10-R/05.2013, SB23, SB33, EHR23, EHR33, Bosch Rexroth AG
5.4 Flange surface sealing element repair
5.4.1 Sealing elements for LS control blocks
Fig. 8: Flange with three tie rods (Standard) Fig. 9: Flange with five tie rods
Table 3: Sealing elements for LS control blocks
Item Quantity Designation Use Dimensions
2 O-ring P, Y18 x 2.5
2 Support ring P, Y
1 O-ring R20 x 2.5
3 Spacer , , , , 0.04
2 O-ring Rx, X, (Ø 8.4 mm) 6 x 1.5
2 O-ring Rx, X, (Ø 11.4 mm) 8 x 2
2 O-ring Rx, X, (Ø 13.6 mm) 10 x 2
1. Remove adhesive spacers that might be available from the flange surface.
2. Remove the O-rings and support rings from the ports P, Y, R, Rx and X.
3. Insert new O-rings and support rings into the ports P, Y, R, Rx and Xin the flange
surface, see Table 4.
Table 4: Sealing element disassembly/assembly for LS control blocks
Port Disassembly Assembly
Pump P
LS Y
Drain oil R
Pilot oil
Feed oil X
Drain oil Rx
Sealing element
disassembly/assembly

12/16 Assembly description
Bosch Rexroth AG, SB23, SB33, EHR23, EHR33, RE 66133-10-R/05.2013
Versions with Rx and Xports that have a counterbore for an O-ring and do not
have a continuous bore through the valve housing, must also be provided with an
O-ring. The O-ring to be used depends on the bore diameter.

Assembly description 13/16
RE 66133-10-R/05.2013, SB23, SB33, EHR23, EHR33, Bosch Rexroth AG
5.5 Shuttle valve repair
Fig. 10: Version for EHR23, SB23 Fig. 11: Version for EHR33, SB33
1. Disassemble the sealing elements of port Y.
2. Remove the shuttle valve from port Y.
3. Insert the shuttle valve in port Yand push it in to the stop without tilting it.
4. Assemble new sealing elements in port Y.
5. Check the distance of 0.5 mm from the flange surface of the control block
segment to the upper edge of the inserted shuttle valve.
Table 5: Shuttle valve disassembly/assembly
Control block segment Disassembly Assembly
EHR23-EM2
SB23-M
SB23-EHS
EHR33
SB33
Disassembly/assembly

14/16 Assembly description
Bosch Rexroth AG, SB23, SB33, EHR23, EHR33, RE 66133-10-R/05.2013
5.6 Coupling flange seals repair
The coupling connections are customer-specific and differ from the presentation.
Table 6: Coupling flange seals
Item Quantity Designation Use Information
2 O-ring Port A, B 18 x 2.5
2 Support ring Port A, B 24.5 x 2.15
1. Dismount the customer-specific coupling connection according to the vehicle
manufacturer’s instructions.
2. Remove the O-rings and the support rings from the working ports Aand B.
Fig. 12: Coupling disassembly
1. Insert the O-rings and support rings into the port Aand B.
2. Assemble the coupling flange according to the vehicle manufacturer’s
instructions.
3. Tighten the mounting screws clockwise applying a torque according to Table 7.
Table 7: Tightening torques mounting screws
Screw M6 M8
Oiled 11+1 Nm 20+3 Nm
Fig. 13: Assembly of the customer-specific coupling flange
Coupling disassembly
Assembly of the customer-
specific coupling flange

Assembly description 15/16
RE 66133-10-R/05.2013, SB23, SB33, EHR23, EHR33, Bosch Rexroth AG
4. For valves with additional functions with access to the coupling flange surface it
must remain accessible even by the use of suitable couplings.
Fig. 14: Coupling flange for valves with additional function

Bosch Rexroth AG
Mobile Applications
Glockeraustraße 4
89275 Elchingen
Germany
Phone [phone]
Fax [phone]
[e-mail]
www.boschrexroth.com/brm
Subject to change without notice
Printed in Germany
RE 66133-10-R/05.2013
Bosch Rexroth AG
Mobile Applications
Robert-Bosch-Straße 2
71701 Schwieberdingen
Germany
Phone [phone]
Fax [phone]
[e-mail]
www.boschrexroth.com/brm