ISO 6621-5:2005
Internal combustion engines - Piston rings - Part 5: Quality requirements

Standard No.

ISO 6621-5:2005

Release Date

2005

Published By

International Organization for Standardization (ISO)

Status

Withdraw

Replace By

ISO 6621-5:2013

Latest

ISO 6621-5:2020

Scope

This part of ISO 6621 specifies those quality aspects that are capable of definition but not normally found on a drawing specification. It covers the following: — single-piece piston rings of grey cast iron or steel; — multi-piece piston rings (oil control rings) consisting of cast iron parts and spring components; — single-piece and multi-piece oil control rings of steel, i.e. oil control rings in the form of strip steel components or steel segments (rails) with spring expander components. In addition to specifying certain of the limits of acceptance relating to inspection measuring principles (covered by ISO 6621-2), this part of ISO 6621 also covers those features for which no recognized quantitative measurement procedures exist and which are only checked visually with normal eyesight (spectacles if worn normally) and without magnification. Such features (superficial defects) are additional to the standard tolerances of ring width, radial wall thickness and closed gap. This part of ISO 6621 does not establish acceptable quality levels (AQL), it being left to manufacturer and client to decide the appropriate levels jointly. In this case, the recommendations of ISO 2859 are followed. This part of ISO 6621 specifies the quality requirements of piston rings for both reciprocating internal combustion engines and compressors working under analogous conditions. It is applicable to all such rings of a diameter ≤ 200 mm.

ISO 6621-5:2005 Referenced Document

• ISO 6621-1 Internal combustion engines - Piston rings - Part 1: Vocabulary*， 2018-02-01 Update
• ISO 6621-3 Internal combustion engines - Piston rings - Part 3: Material specifications*， 2021-05-31 Update
• ISO 6621-4 Internal combustion engines — Piston rings — Part 4: General specifications*， 2024-03-15 Update
• ISO 6622-1 Internal combustion engines - Piston rings - Part 1: Rectangular rings made of cast iron*， 2021-07-31 Update
• ISO 6622-2 Internal combustion engines.Piston rings.Part 2: Rectangular rings made of steel*， 2013-11-01 Update
• ISO 6623 Internal combustion engines.Piston rings.Scraper rings made of cast iron*， 2013-07-01 Update
• ISO 6624-1 Internal combustion engines - Piston rings - Part 1: Keystone rings made of cast iron*， 2017-04-01 Update
• ISO 6624-2 Internal combustion engines - Piston rings - Part 2: Half keystone rings made of cast iron*， 2016-02-01 Update
• ISO 6624-3 Internal combustion engines - Piston rings - Part 3: Keystone rings made of steel*， 2017-04-01 Update
• ISO 6624-4 Internal combustion engines - Piston rings - Part 4: Half keystone rings made of steel*， 2016-02-01 Update
• ISO 6625 Internal combustion engines; Piston rings; Oil control rings
• ISO 6626 Internal combustion engines; piston rings; coil-spring-loaded oil control rings
• ISO 6626-2 Internal combustion engines.Piston rings.Part 2: Coil-spring-loaded oil control rings of narrow width made of cast iron*， 2013-08-01 Update
• ISO 6627 Internal combustion engines — Piston rings — Expander/rail oil-control rings*， 2022-02-25 Update

ISO 6621-5:2005 history

• 2020 ISO 6621-5:2020 Internal combustion engines — Piston rings — Part 5: Quality requirements
• 2013 ISO 6621-5:2013 Internal combustion engines.Piston rings.Part 5: Quality requirements
• 2005 ISO 6621-5:2005 Internal combustion engines - Piston rings - Part 5: Quality requirements
• 1988 ISO 6621-5:1988 Internal combustion engines; piston rings; part 5: quality requirements