SIST EN ISO 2009:2011 PDF

Overview

EN ISO 2009:2011 (ISO 2009:2011) specifies the characteristics of slotted countersunk flat head screws - product grade A with metric external threads from M1.6 to M10 inclusive. Published by ISO and adopted by CEN, this international standard defines dimensional, material and inspection requirements for general-purpose slotted countersunk screws used across mechanical assemblies.

Key topics and technical requirements

• Scope and sizes: Covers nominal thread sizes M1.6 to M10, with associated pitch and preferred lengths defined in the standard.
• Dimensions & head form: Head, slot and shank geometry are given (symbols per ISO 225), including references for head configuration and gauging.
• Materials & property classes:
  • Carbon/alloy steels with property classes 4.8, 5.8
  • Stainless steels such as A2-50, A2-70
  • Non‑ferrous metals also allowed with applicable mechanical property requirements
• Tolerances & thread quality:
  • General purpose metric thread references (ISO 261, ISO 965-2)
  • Tolerance class 6g for external threads
  • Product grade A tolerances per ISO 4759-1
• Mechanical properties & testing:
  • Mechanical requirements referenced to ISO 898-1, ISO 3506-1, and ISO 8839 depending on material
• Surface, coatings and finish:
  • Electroplating requirements per ISO 4042
  • Passivation of stainless steel per ISO 16048
  • Zinc flake coatings per ISO 10683
  • Surface discontinuity limits per ISO 6157-1
• Inspection & acceptance: Acceptance inspection procedures referenced to ISO 3269.
• Designation: Example format - Countersunk flat head screw ISO 2009 - M5 × 20 - 4.8

Practical applications

• Used by manufacturers, fastener suppliers and purchasing engineers specifying slotted countersunk flat head screws for:
  • Consumer products and appliance assembly
  • Sheet-metal work and fastening where a flush countersunk head is required
  • Prototype and repair work where standard metric slotted screws are preferred
• Useful in procurement documents, engineering drawings and quality control plans to ensure interchangeability and consistent performance.

Who should use this standard

• Fastener manufacturers and quality engineers
• Mechanical designers and product engineers
• Procurement professionals and standards compliance officers
• Test laboratories and inspectors performing acceptance checks

Related standards

• ISO 225 (dimensions symbols), ISO 261 / ISO 965-2 (metric threads), ISO 898-1, ISO 3506-1, ISO 4759-1, ISO 4042, ISO 6157-1, ISO 3269, ISO 10683, ISO 16048

This concise reference helps ensure correct specification, interchangeability and quality control when selecting slotted countersunk flat head screws under ISO 2009:2011.