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