Overview
ISO 10096:1997 specifies the dimensions for aerospace hexagonal slotted (castellated) nuts with reduced height and reduced across flats, fitted with MJ threads. Published as the first edition in 1997, the standard covers a set of material-strength/maximum-temperature classifications (for example 450 MPa/425 °C through 1 100 MPa/600 °C) and is intended for use in compiling aerospace product standards. Dimensions and tolerances are given in millimetres and apply after any surface coating(s) but before application of lubricants.
Key topics and technical requirements
- Configuration and dimensions: Defines nut geometry (slots, flats, heights) with reference figures and a tabulated set of sizes and tolerances.
- Strength / temperature classifications: Lists combinations such as 450 MPa / 425 °C, 600 MPa / 235, 315, 650 °C, 900 MPa / 235, 730 °C, and 1 100 MPa / 600 °C. The MPa value is the minimum tensile stress the nut must withstand at ambient temperature (tested with a higher-strength bolt). The temperature is the maximum service temperature without permanent property alteration.
- Threading: Uses MJ threads in accordance with ISO 5855-2 (limit dimensions for MJ bolts and nuts).
- Split-pin use: These nuts are intended for use with split pins conforming to ISO 1234. Table entries indicate maximum split-pin diameters for particular thread sizes.
- Form and position tolerances: Conformance to shape and positional tolerances per ISO 8788. Manufacturers have discretion for unspecified form details (chamfers/radii) within limiting dimensions.
- Measurement basis: Dimensions are specified after coatings but before lubricants; surface texture and pre-coating form tolerances are noted where applicable.
Applications and users
ISO 10096:1997 is primarily used by:
- Aerospace fastener designers and manufacturers (to produce castellated hex nuts to consistent dimensions).
- Procurement and specification writers compiling aerospace product standards.
- Quality assurance, inspection and acceptance teams ensuring fasteners meet dimensional and fit requirements.
- Maintenance and repair organizations specifying replacement parts compatible with split-pin locking methods.
Typical applications include critical aircraft and space vehicle assemblies where reduced-height castellated nuts and MJ threads are required for weight, clearance and locking with split pins.
Related standards
- ISO 1234 - Split pins (compatibility and diameters)
- ISO 5855-2 - Aerospace MJ threads (limit dimensions)
- ISO 8788 - Fastener form and position tolerances
- ISO 9139 - Aerospace procurement specification for plain or slotted nuts
Keywords: ISO 10096:1997, aerospace nuts, hexagonal slotted nuts, castellated nuts, MJ threads, fastener dimensions, split pin, aerospace fastener standards.