# ISO/TR 6624-2:1988 — Withdrawn and superseded ISO standards

For ISO/TR 6624-2:1988, item title is Internal combustion engines — Piston rings — Part 2: Half keystone rings; status code is 9599; successor is ISO/DIS 6624-2 | ISO 6624-2:2003; withdrawn / published date is 1988-12-29, recorded from its source on 2026-08-05.

- **Identifier:** ISO/TR 6624-2:1988 _(verified: appears in the quote below)_
- **Item title:** Internal combustion engines — Piston rings — Part 2: Half keystone rings _(verified: appears in the quote below)_
- **Status code:** 9599 _(verified: appears in the quote below)_
- **Successor:** ISO/DIS 6624-2 | ISO 6624-2:2003
- **Withdrawn / published date:** 1988-12-29 _(verified: appears in the quote below)_

## What the source says

> 13042,TR,,ISO/TR 6624-2:1988,Internal combustion engines — Piston rings — Part 2: Half keystone rings,Moteurs à combustion interne — Segments de piston — Partie 2: Segments demi-trapézoïdaux,1988-12-29,1,['43.060.10'],ISO/TC 22,9599,,"[26901,38357]","['en','fr']",10,"<p>This Technical Report specifies the essential dimensional features of HK- and HKB-half keystone ring types with narrow ring width. Dimension tables 6 and 7 allow for the use of cast iron (table 6) or steel (table 7). The requirements of this Technical Report apply to half keystone rings for reciprocating internal combustion piston engines, up to and including 70 mm diameter for cast iron rings and up to and including 100 mm d

## Source

- https://isopublicstorageprod.blob.core.windows.net/opendata/_latest/iso_deliverables_metadata/csv/iso_deliverables_metadata.csv

Last verified: 2026-08-05. Review by: 2027-02-01.
Part of [Withdrawn and superseded ISO standards](https://referencesource.org/iso-standard-supersessions/).