EN 26157-1:1991
(Main)Fasteners - Surface discontinuities - Part 1: Bolts, screws and studs for general requirements (ISO 6157-1:1988)
Fasteners - Surface discontinuities - Part 1: Bolts, screws and studs for general requirements (ISO 6157-1:1988)
Establishes limits for various types of products and applies also to these products with: nominal thread diameters of 5 mm and larger, product grades A und B, property classes up to and including 10.9; the annex contains a sampling plan.
Verbindungselemente - Oberflächenfehler - Teil 1: Schrauben für allgemeine Anforderungen (ISO 6157-1:1988)
Eléments de fixation - Défauts de surface - Partie 1: Boulons, vis et goujons d'usage général (ISO 6157-1:1988)
La présente partie de l'ISO 6157 fixe les limites des divers types de défauts de surface des vis et goujons d'usage général. Elle s'applique aux vis et goujons
de diamètre nominal de filetage 5 mm et supérieur ;
de grades A et B ;
de classe de qualité inférieure ou égale à 10.9,
sauf spécification contraire dans la norme de produit, ou accord contraire
entre le fournisseur et le client.
Les limites des défauts de surface des vis et goujons pour des applications
particulières (par exemple assemblage automatique) sont fixées
dans l'ISO 6157-3. Si des nécessités techniques exigent un contrôle
plus sévère des défauts de surface des vis ou goujons,
il convient de le spécifier dans la norme de produit correspondante,
ou d'indiquer dans l'appel d'offres et la commande les limites acceptables.
La présence de défauts de surface dans les limites admises dans
le chapitre 3 ne doit cependant pas affecter le respect des valeurs minimales
de caractéristiques mécaniques et fonctionnelles spécifiées
dans IISO 898-l.
NOTES
1 Les figures données en illustration dans le chapitre 3 ne sont que
des exemples. Elles sappliquent également à dautres
types de vis ou goujons.
2 Les schémas représentent dans certains cas une exagération
des défauts pour une meilleure compréhension.
Vezni elementi - Površinske napake - 1. del: Vijaki za splošne zahteve
General Information
- Status
- Published
- Publication Date
- 15-Oct-1991
- Technical Committee
- CEN/TC 185 - Threaded and nonthreaded mechanical fasteners and accessories
- Current Stage
- 9093 - Decision to confirm - Review Enquiry
- Start Date
- 28-Jul-2006
- Completion Date
- 28-Jul-2006
Relations
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
Overview
EN 26157-1:1991 - Fasteners - Surface discontinuities - Part 1: Bolts, screws and studs for general requirements (ISO 6157-1:1988) is a CEN standard that establishes limits and acceptance criteria for surface discontinuities on common threaded fasteners. The standard applies to bolts, screws and studs with nominal thread diameters of 5 mm and larger, for product grades A and B, and for property classes up to and including 10.9. An annex provides a sampling plan for inspection.
This standard is identical to ISO 6157-1:1988 and has been adopted in national implementations (for example SIST EN 26157-1).
Key topics and technical requirements
- Scope and applicability: Defines which fasteners are covered (diameter ≥ 5 mm, grades A/B, property classes ≤ 10.9).
- Types of surface discontinuities: Describes categories of surface defects that can affect performance and appearance (e.g., laps, cracks, seams, tears) - the standard sets limits for such discontinuities.
- Acceptance criteria: Establishes limits and criteria for when a fastener is acceptable, conditionally acceptable, or rejected due to surface discontinuities.
- Sampling plan: Annex includes a sampling procedure to determine lot conformity without inspecting every item, enabling statistically based quality control.
- Reference to ISO series: Aligned with ISO 6157-1:1988, enabling harmonized inspection and procurement across international markets.
(Note: EN 26157-1 sets the framework and acceptance limits rather than prescriptive manufacturing steps. For detailed inspection techniques or measurement procedures, refer to complementary documents or inspection standards.)
Applications
- Quality control and acceptance testing in fastener manufacturing lines.
- Incoming inspection criteria for suppliers and procurement teams in automotive, construction, machinery and general engineering.
- Defining contractual acceptance criteria in purchase orders and specifications to ensure consistent product quality.
- Guiding inspection plans for third-party auditors and certification bodies.
- Useful for design engineers and maintenance teams who need assurance that fasteners meet surface integrity requirements to avoid fatigue or corrosion initiation.
Who uses this standard
- Fastener manufacturers and production engineers
- Quality assurance and inspection teams
- Procurement and sourcing professionals
- Mechanical designers and reliability engineers
- Third‑party testing and certification bodies
Related standards
- ISO 6157-1:1988 (identical content)
- Other parts of the ISO 6157 series and national adoptions (for full series context and related defect classification)
Keywords: EN 26157-1:1991, fasteners, surface discontinuities, bolts screws studs, ISO 6157-1, sampling plan, nominal thread diameter 5 mm, product grades A B, property class 10.9, CEN.
Frequently Asked Questions
EN 26157-1:1991 is a standard published by the European Committee for Standardization (CEN). Its full title is "Fasteners - Surface discontinuities - Part 1: Bolts, screws and studs for general requirements (ISO 6157-1:1988)". This standard covers: Establishes limits for various types of products and applies also to these products with: nominal thread diameters of 5 mm and larger, product grades A und B, property classes up to and including 10.9; the annex contains a sampling plan.
Establishes limits for various types of products and applies also to these products with: nominal thread diameters of 5 mm and larger, product grades A und B, property classes up to and including 10.9; the annex contains a sampling plan.
EN 26157-1:1991 is classified under the following ICS (International Classification for Standards) categories: 21.060.10 - Bolts, screws, studs. The ICS classification helps identify the subject area and facilitates finding related standards.
EN 26157-1:1991 has the following relationships with other standards: It is inter standard links to EN 14399-10:2009, EN 14399-7:2007, EN 14399-10:2018, EN 14399-7:2018, EN 14399-4:2005, EN 14399-8:2018, EN 14399-4:2015, EN 14399-3:2005, EN 14399-3:2015, EN 14399-8:2007. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
EN 26157-1:1991 is associated with the following European legislation: EU Directives/Regulations: 97/23/EC; Standardization Mandates: M/071. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.
EN 26157-1:1991 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Vezni elementi - Površinske napake - 1. del: Vijaki za splošne zahteveVerbindungselemente - Oberflächenfehler - Teil 1: Schrauben für allgemeine Anforderungen (ISO 6157-1:1988)Eléments de fixation - Défauts de surface - Partie 1: Boulons, vis et goujons d'usage général (ISO 6157-1:1988)Fasteners - Surface discontinuities - Part 1: Bolts, screws and studs for general requirements (ISO 6157-1:1988)21.060.10
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.
Loading comments...