Overview
ISO 4580:2021 - Aerospace - Drives, internal, TORX® PARALOBE® driver bit - Geometrical definition, gaging and technical requirements - defines the basic dimensions, characteristics and engineering requirements for TORX® PARALOBE® driver bits used with aerospace fasteners. The standard covers dimensional data in both metric and inch units, marking and designation, inspection gaging, and torque testing procedures and apparatus requirements. (Note: TORX® PARALOBE® is a registered trademark; equivalent drives may be used if they produce equivalent results.)
Key Topics
- Geometrical definition
- Basic driver bit configuration and required dimensions (⌀A, ⌀B, L) provided in metric and inch tables.
- Drive size descriptors and manufacturer marking requirements.
- Designation and marking
- Standardized driver bit designation (example format: ISO 4580-025) and surface marking requirements to identify drive size and manufacturer.
- Gaging and inspection
- Go / no‑go driver bit inspection gage design and identification.
- Gage body dimensions (X, Y, Z) and circumscribed/inscribed diameters (⌀D, ⌀K, ⌀G) listed per drive size in metric and inch tables.
- Recommended measurement methods (e.g., calliper for configuration length L) and conformity to applicable military, industry or manufacturer data.
- Torque testing
- Requirements for torque test apparatus to maintain alignment, apply end load and torque without inducing bending moments or resisting cam‑out.
- Torque test fixture configuration, including required hardness (fixture configuration hardness specified) and pin arrangement to set configuration depth (P).
- Procedure and equipment references (torque wrench / torsion machine) with torque values tabulated by drive size.
Applications
ISO 4580:2021 is directly applicable to:
- Aerospace tool and fastener manufacturers designing or producing TORX PARALOBE driver bits.
- Assembly and maintenance organizations that require standardized driver bits for aerospace fasteners.
- Quality assurance and inspection teams performing go/no‑go gauging and torque verification.
- Procurement and supplier qualification groups specifying driver bit geometry, gaging and torque performance in contracts and technical data packages.
Using ISO 4580 helps ensure interchangeability, correct torque transfer, repeatable inspection and improved reliability for internal drive aerospace fasteners.
Related Standards
- ISO 4579 - Aerospace - Drives, internal, TORX® PARALOBE® drive - geometrical definition, gaging and technical requirements (drive geometry for fasteners referenced by ISO 4580).
- Applicable military standards, industry standards or manufacturer’s data for driver bit body dimensions and application‑specific requirements.
Keywords: ISO 4580:2021, TORX PARALOBE, driver bit, aerospace fasteners, geometrical definition, gaging, torque test, inspection gage, driver bit designation.