ISO 24652:2023

INTERNATIONAL ISO
STANDARD 24652
First edition
2023-09
Spherical plain bearings — Spherical
plain bearings rod ends for hydraulic
fluid power cylinders
Rotules lisses — Embouts à rotule pour vérins hydrauliques
Reference number
© ISO 2023
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 2
5 Design . 3
6 Dimensions .10
6.1 General . 10
6.2 Spherical plain bearings rod end, welded type . 11
6.3 Spherical plain bearings rod end, threaded type . 13
7 Technical requirements .18
7.1 Material and heat treatment . 18
7.1.1 Inner ring and outer ring . 18
7.1.2 Rod end housing . 18
7.1.3 Hexagon socket head cap screws . 18
7.2 Tolerances . 18
7.2.1 Rod end inner ring . 18
7.2.2 Deviation of centre height Δ and Δ . 19
h1s h2s
7.2.3 Tolerance class for thread . 20
7.3 Radial internal clearances . 20
7.4 Surface roughness . 21
7.5 Surface treatments . 21
7.6 Rotation and oscillation flexibility . 21
7.7 Load ratings and life . 21
Annex A (informative) Symbols/identification codes .22
Annex B (informative) Fixation by retaining rings .23
Annex C (informative) Mounting example — Spherical plain bearing rod end on hydraulic
fluid power cylinders .28
Annex D (informative) Surfaces — Features .30
Bibliography .32
iii
Foreword
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This document was prepared by Technical Committee ISO/TC 4, Rolling bearings, Subcommittee SC 7,
Spherical plain bearings, in collaboration with Technical Committee ISO/TC 131, Fluid power systems,
Subcommittee SC 3, Cylinders.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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iv
Introduction
In hydraulic fluid power systems, power is transmitted and controlled through a fluid (liquid) under
pressure within an enclosed circuit.
One component of such systems is the fluid power cylinder. This is a device that converts power into
linear mechanical force and motion. It consists of a moveable element, i.e. a piston and a piston rod,
operating within a cylindrical bore.
The spherical plain bearings rod ends are used on piston rods of hydraulic cylinders for mechanical
transmitting the cylinder force under oscillatory rotational and tilting movements. The design of the
spherical plain bearing rod ends is based on the maximum forces resulting from the specified internal
diameter of the cylinders and pressure according to the ISO 6020 series and ISO 6022.
The dimensions and tolerances specified in this document have been selected to permit the design
and use of spherical plain bearings rod ends which incorporate radial spherical plain bearings having
various sliding material combinations. These spherical plain bearings can be requiring maintenance
(steel/steel or steel/bronze), maintenance-free [e.g. steel/polytetrafluoroethylene (PTFE)] and/or
sealed.
NOTE Spherical plain bearings rod ends for hydraulic fluid power cylinders can be used for other applications
than hydraulic fluid power cylinders as well.
Type D and Type E from this document are in the scope of ISO 8132 and ISO 8133.
v
INTERNATIONAL STANDARD ISO 24652:2023(E)
Spherical plain bearings — Spherical plain bearings rod
ends for hydraulic fluid power cylinders
1 Scope
This document specifies designs, dimensions, tolerances and technical requirements of spherical plain
bearings rod ends for hydraulic fluid power cylinders.
The specified tolerance values apply to finished spherical plain bearing rod ends before any coating,
plating, ring splitting or fracturing.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 68-1, ISO general purpose screw threads — Basic profile — Part 1: Metric screw threads
ISO 286-2, Geometrical product specifications (GPS) — ISO code system for tolerances on linear sizes —
Part 2: Tables of standard tolerance classes and limit deviations for holes and shafts
ISO 582:1995, Rolling bearings — Chamfer dimensions — Maximum values
ISO 965-1, ISO general purpose metric screw threads — Tolerances — Part 1: Principles and basic data
ISO 1132-1, Rolling bearings — Tolerances — Part 1: Terms and definitions
ISO 4762, Hexagon socket head cap screws
ISO 5598, Fluid power systems and components — Vocabulary
ISO 6811, Spherical plain bearings — Vocabulary
ISO 8132, Hydraulic fluid power — Mounting dimensions for accessories for single rod cylinders, 16 MPa
(160 bar) medium and 25 MPa (250 bar) series
ISO 8133, Hydraulic fluid power — Mounting dimensions for accessories for single rod cylinders, 16 MPa
(160 bar) compact series
ISO 12240-1:1998, Spherical plain bearings — Part 1: Radial spherical plain bearings
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 1132-1, ISO 5598, ISO 6811
and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
spherical plain bearings rod end, welded type
spherical plain bearings rod end having a welding chamfer or a welding shank at the bottom for
fastening the rod end to the cylinder by welding
3.2
spherical plain bearings rod end, threaded type
spherical plain bearings rod end having an internal thread that is connected to the cylinder by thread,
with or without locking device
3.3
angle of tilt of bearing
α
permissible angular displacement of the inner member relative to the outer member of a spherical plain
bearing or rod end
Note 1 to entry: See Figure 1.
Figure 1 — Angle of tilt of a bearing
Note 2 to entry: Attention is drawn to the fact that after mounting a spherical plain bearing rod end on a shaft,
the angle through which the rod end can tilt can be restricted by design of adjacent components.
[SOURCE: ISO 6811:1998, 03.02.01, modified — "of bearing" has been added to the term and, Figure 1
and Note 1 to entry have been added.]
4 Symbols
For the purposes of this document, the symbols in Table 1 apply.
The symbols (except those for tolerances) shown in the Figures 1 to 3 and the values given in Tables 2 to
10 denote nominal dimensions, unless otherwise specified.
Table 1 — Symbols
Symbol/identification
Symbol code according to Description Unit
a
ISO 6099
B EN Inner ring width mm
b – Width of thread connected side of rod end mm
C EU Width of rod end eye mm
d CN Bore diameter of inner ring mm
d – Sphere diameter mm
k
a
ISO 6099 covers the identification codes for cylinder mounting dimensions and accessories (see Annex A).
TTabablele 1 1 ((ccoonnttiinnueuedd))
Symbol/identification
Symbol code according to Description Unit
a
ISO 6099
d 2EF Outside diameter of rod end eye mm
d N Rod end shank shoulder diameter mm
d – Rod end shank diameter for welding end mm
d – Locating pin diameter mm
d – Diameter of small flange step of rod end mm
d – Diameter of large flange step of rod end mm
d – Flange diameter for welded end mm
e – Chamfer dimension for welded end mm
F – Nominal cylinder force kN
n
G KK Designation of thread mm
h CH Centre height of threaded rod end mm
h – Centre height of welded rod end mm
L – Width of bottom side of threaded rod end mm
l AV Thread length mm
l – Overall length of threaded rod end mm
l – Overall length of welded rod end mm
Length from the bearing bore centre to the stepped
l LF mm
surface of shank
l – Length of locating pin mm
l – Depth of thread hole mm
Ra – Surface roughness µm
r – Single chamfer dimension of inner ring mm
s
V – Variation of mean bore diameter µm
dmp
V – Variation of bore diameter in a single radial plane µm
dsp
α Z Angle of tilt of bearing °
Δ – Deviation of a single inner ring width µm
Bs
Δ – Deviation of mean bore diameter in a single plane µm
dmp
Δ – Deviation of centre height of threaded rod end mm
h1s
Δ – Deviation of centre height of welded rod end mm
h2s
a
ISO 6099 covers the identification codes for cylinder mounting dimensions and accessories (see Annex A).
Annex A shows an application example of the symbols according to this document and the identification
codes of ISO 6099.
5 Design
The rod end bearings for hydraulic cylinders comprise a radial spherical plain bearing and a rod end
housing. The spherical plain bearing rod end, welded type for hydraulic cylinders is shown in Figure 2,
and threaded type is shown in Figure 3.
NOTE 1 The figures only show an example of the design. For example, the design from Figure 3 a) can have
two screws on one side. Conformity with the designs illustrated is not required.
Table 2 gives an overview about the different design variants.
NOTE 2 With or without lubricating nipple or lubrication hole. Type and design of lubricating nipple or
lubrication hole at manufacturer’s discretion.
NOTE 3 The spherical plain bearings can be axially located in the housing by means of retaining rings.
NOTE 4 A suitable thread locking device can be used.
NOTE 5 Differences in shape of the rod end housing depending on the manufacturer’s processes can occur.
Table 2 — Overview of rod end designs
Dimension
a
Basic type Type Remark 1 Remark 2 Figure
series
Rod ends with a cylin- Spherical plain
drical welding section E bearing unassisted – 2 a)
with locating pin of retaining rings
Welded type Rod ends with a welding
E – 2 b)
chamfer
Rod ends with a rectan-
E, W – 2 c)
gular welding section
Thread locking
device by two
hexagon socket
head cap screws
b
A E left and/or 3 a)
right of the
internal thread
Spherical plain bear-
of the rod end
ing located by means
c shank
of retaining rings
b
B E - 3 b)
Thread locking
device by two
hexagon socket
Threaded
d head cap screws
b
type
C E 3 c)
on one side
of the internal
thread of the
rod end shank
b
D W Thread locking 3 d)
device by two
hexagon socket
head cap screws
Spherical plain
left and/or
b
E E bearing unassisted 3 e)
right of the
of retaining rings
internal thread
of the rod end
shank
a
Spherical plain bearing shall be in accordance with ISO 12240-1.
b
The different stud holes are given for d ≤ 30 mm and d > 30 mm.
c
See Annex B.
d
Threads shall be in accordance with ISO 68-1.
Retaining rings and retaining ring grooves are shown in Annex B. Annex C shows a mounting example
of a spherical plain bearing rod end on a hydraulic fluid power cylinder.
a) Rod ends with a cylindrical welding section with locating pin
b) Rod ends with a welding chamfer
c) Rod ends with a rectangular welding section
Figure 2 — Spherical plain bearings rod end, welded type
d ≤ 30 mm d > 30 mm
a) Type A
d ≤ 30 mm d > 30 mm
b) Type B
d ≤ 30 mm d > 30 mm
c) Type C
d ≤ 30 mm d > 30 mm
d) Type D
d ≤ 30 mm d > 30 mm
e) Type E
Figure 3 — Spherical plain bearings rod end, threaded type
6 Dimensions
6.1 General
Dimensions shall be as shown in Figures 2 a) to 2 c) and 3 a) to 3 e) and values as given in Tables 3 to 10.
Where “max.” is shown in Tables 3 to 10, this indicates that the value is the largest actual value
permitted. Where “min.” is shown in Tables 3 to 10, this indicates that the value is the smallest actual
value permitted.
NOTE For nominal values as well as tolerance values, the manufacturer can be contacted.
The corresponding largest single chamfer dimensions to the r dimensions in Tables 3 to 10 shall be as
s
given in ISO 582:1995, Table 1.
Load requirements according to ISO 8132 and ISO 8133 are currently only assigned to spherical plain
bearings rod end, threaded type, Type D in Table 9, and Type E in Table 10.
6.2 Spherical plain bearings rod end, welded type
Table 3 — Rod ends with a cylindrical welding section with locating pin
a b
d B d C d h l l l d d e r α
k 1 2 2 6 7 8 5 6 s
max. max. min. max. min. ≈
mm mm mm mm mm mm mm mm mm mm mm mm mm °
10 9 16 7,5 30 24 40 15 6 16 3 1 3 0,3 12
12 10 18 8,5 35 27 45 17,5 6 19 3 1 3 0,3 10
15 12 22 10,5 41 31 52 20 6 22 4 1,5 3,5 0,3 8
c
16 14 25 11,5 47 35 59 23 6 25 4 1,5 4 0,3 10
17 14 25 11,5 47 35 59 23 6 25 4 1,5 4 0,3 10
20 16 29 13,5 54 38 66 27,5 6 29 4 1,5 4 0,3 9
c
25 20 35,5 18 65 45 78 33 6 35 4 2,5 5 0,6 7
c
30 22 40,7 20 75 51 89 37,5 6 42 4 2,5 5 0,6 6
35 25 47 22 84 61 104 43 6 49 4 2,5 5 0,6 6
40 28 53 24 94 69 118 48 6 54 4 3 6 0,6 7
45 32 60 28 104 77 132 52 6 60 6 3 6 0,6 7
50 35 66 31 114 88 150 59 6 64 6 3 7 0,6 6
60 44 80 39 137 100 173 72,5 6 72 6 3 10 1 6
70 49 92 43 162 115 199 85,5 6 82 6 4 12 1 6
80 55 105 48 182 141 237 98 6 97 6 4 12 1 6
a
This value is given for reference only.
b
Attention is drawn to the fact that, after mounting a spherical plain bearing rod end on a shaft, the angle through which
the rod end can tilt can be restricted by design of adjacent components.
c
These values deviate from ISO 12240-1.
Table 4 — Rod ends with a welding chamfer
a b
d B d C d h l l d d d r α
k 1 2 2 7 6 7 8 9 s
max. max.   ≈ min. ≈
mm mm mm mm mm mm mm mm mm mm mm mm °
20 16 29 19,2 51 48,5 38 73,5 35 37 45 0,3 9
25 20 35,5 23,2 56 57,5 45 85 50 52 60 0,6 7
30 22 40,7 28,2 66 63,5 51 96 60 62 70 0,6 6
35 25 47 30,2 84,5 73,5 61 115 70 72 80 0,6 6
40 28 53 35,2 101,5 84,5 69 134,5 85 87 100 0,6 7
50 35 66 40,5 125 106,5 88 168 110 112 130 0,6 6
60 44 80 50,5 142 120,5 100 190,5 130 133 150 1 6
a
This value is given for reference only.
b
Attention is drawn to the fact that, after mounting a spherical plain bearing rod end on a shaft, the angle through which
the rod end can tilt can be restricted by design of adjacent components.
Table 5 — Rod ends with a rectangular welding section
a c
d B d C d h l r α
k 1 2 2 6 s
b
Bearing series max. max. min. ≈
mm mm mm mm mm mm mm mm °
15 12 22 E 16,2 46 31 53,5 0,3 8
corresponding
16 14 25 17,7 49 35 59 0,3 10
to E
16 16 23 W 17,7 49 35 59 0,3 10
17 14 25 E 17,7 49 35 59 0,3 10
20 16 29 E 20 51,5 38 63 0,3 9
20 20 29 W 20 51,5 38 63 0,3 4
25 20 35,5 E 24 56,5 45 72,5 0,6 7
25 25 35,5 W 24 56,5 45 72,5 0,6 4
30 22 40,7 E 29 66,5 51 83,5 0,6 6
32 32 43 W 29 71,5 65 100 0,6 4
35 25 47 E 31 85 61 102,5 0,6 6
40 28 53 E 36,5 102 69 119 0,6 7
40 40 53 W 36,5 102 69 119 0,6 4
45 32 60 E 41,5 112 77 132 0,6 7
50 35 66 E 41,5 125,5 88 149,5 0,6 6
50 50 66 W 41,5 125,5 88 149,5 0,6 4
60 44 80 E 51,5 142,5 100 170 1 6
63 63 83 W 51,5 147 107 179,5 1 4
70 49 92 E 57 166,5 115 197 1 6
corresponding
70 70 92 57 166,5 115 197 1 4
to W
80 55 105 E 62 182,5 141 231 1 6
80 80 105 W 62 182,5 141 231 1 4
90 60 115 E 67 228,5 150 263 1 5
corresponding
90 90 115 67 228,5 150 263 1 4
to W
100 70 130 E 72 252,5 170 295 1 7
100 100 130 W 72 252,5 170 295 1 4
110 70 140 E 83 298 185 332,5 1 6
corresponding
110 110 140 83 298 185 332,5 1 6
to W
120 85 160 E 92,5 363 210 390 1 6
a
This value is given for reference only.
b
Bearing series shall be in accordance with ISO 12240-1.
c
Attention is drawn to the fact that, after mounting a spherical plain bearing rod end on a shaft, the angle through which
the rod end can tilt can be restricted by design of adjacent components.
6.3 Spherical plain bearings rod end, threaded type
Table 6 — Type A
a b c
d B d C d G h l l l l d L b r α Screw
k 1 2 1 3 33 4 7 4 s
max. max. min. max.   min. ≈
mm mm mm mm mm mm mm mm mm mm mm mm mm mm °
20 16 29 19,5 58 M16×1,5 50 17 – 80 25 25 20 0,3 9 M8×20
d
25 20 35,5 23,5 58 M16×1,5 50 17 – 80 25 25 21 0,6 7 M8×20
d
...