Overview
ISO 10510:2011 - "Tapping screw and washer assemblies with plain washers" - specifies requirements for assembled tapping screws and captive plain washers with thread sizes ST2,2 to ST9,5 inclusive, flat seating heads and mechanical properties as specified in ISO 2702. The standard covers dimensional conditions for assembled parts, mechanical and hardness requirements for washers, and rules for designation and referencing the assemblies.
Key topics and requirements
- Scope and components
- Applies to tapping screw + plain washer assemblies where the washer is captive (prevented from disassembly but free to rotate).
- Covers common head styles (hexagon, cross‑recessed pan, slotted pan) and thread end types per ISO 1478.
- Thread sizes
- Thread series covered: ST2,2 through ST9,5.
- Dimensions and assembly rules
- Assembled dimensions generally follow the relevant product standards for loose screws, with specific exceptions:
- Shank diameter must allow the washer (ISO 10669) to rotate freely.
- Distance from underside of head to first full thread is increased by the washer thickness.
- Transition diameter reduced by the difference between nominal and thread-rolling diameter.
- Mechanical properties
- Screw mechanical properties: those specified in ISO 2702 (heat-treated steel tapping screws).
- Washer hardness and testing
- Washer hardness after assembly and heat treatment: 90 HV to 320 HV.
- Vickers hardness testing per ISO 6507-1:
- Test force HV10 for nominal thickness ≤ 1,2 mm.
- Test force HV30 for nominal thickness > 1,2 mm.
- Precautions to avoid detrimental case hardening of washers during heat treatment (e.g., copper plating) are required.
- Designation
- A standardized designation format (ISO 10510 – thread × length – end type – screw symbol – washer symbol) is provided with examples.
Applications and who uses ISO 10510
- Intended for fastener manufacturers, product designers, quality and test engineers, procurement/specification teams, and OEMs in industries using self-tapping screws (electronics, appliances, furniture, construction, automotive interiors).
- Useful when specifying captive plain-washer tapping screw assemblies to ensure dimensional compatibility, mechanical performance, traceable designation, and conformity to international practice.
Related standards
- ISO 2702 - Heat-treated steel tapping screws - Mechanical properties
- ISO 10669 - Plain washers for tapping screw and washer assemblies (normal & large series)
- ISO 1478 - Tapping screws thread
- ISO 1479 - Hexagon head tapping screws
- ISO 1481 - Slotted pan head tapping screws
- ISO 7049 - Cross-recessed pan head tapping screws
- ISO 6507-1 - Vickers hardness test method
Keywords: ISO 10510, tapping screw and washer assemblies, plain washers, captive washer, ISO 2702, ISO 10669, Vickers hardness, tapping screws.
