ISO 6626-1:2024
(Main)Internal combustion engines — Piston rings — Part 1: Coil spring loaded oil control rings made of cast iron
Internal combustion engines — Piston rings — Part 1: Coil spring loaded oil control rings made of cast iron
This document specifies the essential dimensional features of coil-spring loaded oil control rings made of cast iron, types DSF-C, DSF-CNP, SSF, GSF, DSF, DSF-NG and SSF-L. It is applicable to piston rings in sizes from 60 mm up to and including 200 mm for reciprocating internal combustion engines for road vehicles and other applications.
Moteurs à combustion interne — Segments de piston — Partie 1: Anneaux de contrôle de l'huile à ressort hélicoïdal en fonte
General Information
Relations
Standards Content (Sample)
International
Standard
ISO 6626-1
First edition
Internal combustion engines —
2024-07
Piston rings —
Part 1:
Coil spring loaded oil control rings
made of cast iron
Moteurs à combustion interne — Segments de piston —
Partie 1: Anneaux de contrôle de l'huile à ressort hélicoïdal en fonte
Reference number
© ISO 2024
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Published in Switzerland
ii
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Overview . 1
5 Piston ring types and designation . 2
5.1 Types DSF-C, DSF-CNP, SSF, GSF, DSF, DSF-NG and SSF-L — General features and
dimensions .2
5.2 Type DSF-C ─ Coil-spring loaded bevelled edge oil control ring, chromium plated and
profile ground .2
5.2.1 General features and dimensions .2
5.2.2 Example designation of a type DSF-C piston ring in accordance with this
document .3
5.3 Type DSF-CNP ─ Coil-spring loaded bevelled edge oil control ring, chromium plated
not profile ground .3
5.3.1 General features and dimensions .3
5.3.2 Example designation of a type DSF-CNP piston ring in accordance with this
document .4
5.4 Type SSF ─ Coil-spring loaded slotted oil control ring .4
5.4.1 General features and dimensions .4
5.4.2 Example designation of a type SSF piston ring in accordance with this document .5
5.5 Type GSF ─ Coil-spring loaded double bevelled oil control ring .5
5.5.1 General features and dimensions .5
5.5.2 Example designation of a type GSF piston ring in accordance with this document .6
5.6 Type DSF ─ Coil-spring loaded bevelled edge oil control ring .6
5.6.1 General features and dimensions .6
5.6.2 Example designation of a type DSF piston ring in accordance with this document .7
5.7 Type DSF-NG ─ Coil-spring loaded bevelled edge oil control ring (face geometry similar
to type DSF-C or type DSF-CNP) .7
5.7.1 General features and dimensions .7
5.7.2 Example designation of a type DSF-NG piston ring in accordance with this
document .8
5.8 Type SSF-L ─ Coil-spring loaded slotted oil control ring with h1 = 4,75 mm (3/16 in)
ring width and 0,6 mm nominal land width.8
5.8.1 General features and dimensions .8
5.8.2 Example designation of a type SSF-L piston ring in accordance with this
document .9
6 Common features . 9
6.1 Oil drainage by slots or holes .9
6.1.1 Arrangement of slots .9
6.1.2 Slot length .11
6.1.3 Arrangement of holes .11
6.1.4 Diameter and number of holes .11
6.2 Plating thickness — DSF-C and DSF-CNP Coil-spring loaded oil control rings .11
6.3 Peripheral edges at gap of chromium plated oil control rings . 12
6.4 Spring groove and land offsets. 12
7 Coil springs .12
7.1 Types of coil spring . 12
7.2 Latch pin and location of small pitch in the coil spring .14
7.3 Coil spring excursion (extended gap) .14
7.4 Position of coil spring gap and fixing . 15
iii
7.5 Material . 15
8 Tangential force and nominal contact pressure .15
8.1 Tangential force, F . 15
t
8.1.1 Force factors . 15
8.1.2 General tangential force, F .16
t
8.1.3 Actual tangential force, F , and tolerance .16
t
8.1.4 Normalized tangential force, F .16
N
8.2 Nominal contact pressure, p .16
o
9 Dimensions .16
Annex A (informative) Historical classes of nominal contact pressure, p .78
o
Bibliography .80
iv
Foreword
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This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 34,
Propulsion, powertrain and powertrain fluids.
This first edition cancels and replaces ISO 6626:1989, which has been technically revised.
The main changes are as follows:
— classes of nominal contact pressure were moved to Annex A and the normalized tangential force was
introduced;
— verification and correction of figures;
— update of dimension Tables 8 to 25.
A list of all parts in the ISO 6626 series
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