ISO 4026:2026

Overview

ISO 4026:2026 specifies the requirements for hexagon socket set screws with flat point, focusing on their mechanical and dimensional characteristics. These fasteners are widely used for secure, precise assembly in mechanical, industrial, and automotive applications. The standard covers metric coarse pitch threads ranging from M1.6 to M30 for steel and M1.6 to M24 for stainless steel, targeting applications where secure, non-tensile load fastening is required. Screws are classified as product grade A, suitable for high-precision and high-quality requirements.

Key Topics

• Fastener Types Covered: Hexagon socket set screws with flat points, designed for use in assemblies where a flush or non-intrusive fastening is needed.
• Thread Specifications: Applicable thread sizes are M1.6-M30 for steel and M1.6-M24 for stainless steel, based on metric coarse pitch threads.
• Material Standards: Steel and stainless steel options are included, with hardness classes and grades selectable in line with ISO 898-5 (for steel) or ISO 3506-3 (for stainless steel).
• Dimensional Accuracy: Conformance with ISO 225 for dimensions, ISO 724 for basic screw thread dimensions, and ISO 965-1 for tolerances.
• Surface Conditions: Requirements for as-processed, clean and bright, passivated, electroplated, or zinc-flake coated finishes as per ISO 4042 and ISO 10683.
• Labelling and Marking: Package labelling must provide full product traceability, including reference to ISO 4026, thread size, nominal length, material class or grade, surface condition, lot number, and quantity.
• Quality and Inspection: Inspection and acceptance requirements follow ISO 3269 and ISO 1891-4, ensuring standard-compliant products.

Applications

Hexagon socket set screws with flat point as defined in ISO 4026:2026 are integral to:

• Mechanical Assembly: Used in machinery, automobiles, and industrial equipment to fix components without protrusions, enhancing safety and mechanical function.
• Precision Engineering: The flat point provides uniform contact without damaging the mating surface, making these fasteners suitable for precision settings, electronics, and instrumentation.
• Maintenance and Repairs: Easily inserted and removed using a hex key, allowing for efficient serviceability in manufacturing lines and repair shops.
• Custom Fastening Solutions: The standard offers the flexibility to choose material grades, hardness classes, and finishes suitable for specific environments, including corrosive or high-wear applications.

Related Standards

To complement ISO 4026:2026, several related ISO fastener standards support specification and application:

• ISO 898-5: Mechanical properties for steel set screws and similar fasteners
• ISO 3506-3: Mechanical properties for stainless steel set screws
• ISO 888: Specification of nominal and thread lengths
• ISO 965-1: General purpose metric screw thread tolerances
• ISO 4042 and ISO 10683: Guidelines for fastener coating, including electroplating and zinc-flake coatings
• ISO 4753: Dimensional requirements for ends of externally threaded parts
• ISO 8991: Designation systems for fasteners, ensuring clear and standardized product descriptions
• ISO 6157-1: Surface discontinuities and integrity requirements
• ISO 3269: Product acceptance and inspection guidelines

Adhering to ISO 4026:2026 ensures the use of high-quality, reliable hexagon socket set screws with flat point, supporting improved assembly practices, product consistency, and international trade compatibility across industrial sectors.