ISO 2351-1:2007

Overview

ISO 2351-1:2007 specifies technical requirements for machine-operated screwdriver bits for slotted head screws. It covers bits with a male hexagon drive or a cylindrical flat end drive (as defined in ISO 1173) and tips for screwdriver Type C (per ISO 2380-1). The standard defines dimensions, recommended tip‑to‑bit combinations, torque testing reference, designation and marking practices to ensure interchangeability, safety and reliable fastening performance in machine-driven applications.

Key topics and requirements

• Scope and applicability: Applies to machine-operated bits designed for slotted head screws, including drive-end forms referenced in ISO 1173 and Type C tips from ISO 2380-1.
• Dimensions and combinations: Provides recommended combinations of tip thickness/width and driver‑end forms (dimensions given in millimetres). The standard includes a table and figure showing compatible tip sizes and driver ends to help select correct bit/tip pairings.
• Technical requirements: Bits must meet the technical specifications for screwdriver tips Type C in ISO 2380-1 (material, shape, tolerances where applicable).
• Torque testing: Torque tests are to be performed in accordance with ISO 2380-1 (Type C), ensuring bits withstand the mechanical stresses expected in machine operation.
• Designation: Prescribes a consistent designation format (e.g., Bit ISO 2351-1 E 11,2 − 1,6 × 8) that combines the part reference, driver-end form and tip dimensions for unambiguous identification.
• Marking: Requires permanent, legible marking of the manufacturer/supplier name and tip dimensions (a × b). Exception: for certain small male hexagon types (A3 and C4), marking on the smallest packaging unit is acceptable.

Applications and users

Who benefits from ISO 2351-1:2007:

• Tool manufacturers and bit designers - for compliant product design and labeling.
• Assembly equipment and automation engineers - to select compatible bits for power screwdrivers and automatic screwdrivers.
• Quality engineers and test labs - to perform torque testing and verify conformity.
• Procurement and spec writers - to specify interchangeability and reduce mismatch risk in production lines.
• Maintenance and service organizations - to ensure correct bit selection for repair and assembly tasks.

Typical applications:

• High-volume manufacturing (automotive, electronics, appliances) using machine-operated screwdrivers.
• Automated or semi-automated fastening stations where consistent bit geometry and torque performance are critical.

Related standards

• ISO 1173 - Drive ends for hand- and machine-operated screwdriver bits.
• ISO 2380-1 - Screwdrivers for slotted-head screws, Part 1: Tips (Type C) and torque test methods.
• ISO 2351-2 and ISO 2351-3 - Parts 2 and 3 cover cross‑recessed and hexagon socket screwdriver bits respectively.
• ISO 1703 - Designation and nomenclature for assembly tools.

Keywords: ISO 2351-1:2007, machine-operated screwdriver bits, slotted head screws, ISO 1173, ISO 2380-1, torque test, bit designation, bit marking, bit dimensions, recommended combinations.