# Rivet nuts

Blind threaded rivet-nut mechanisms, grip and hole geometry, product variants, and the limits of catalogue performance data.

Reviewed: 2026-10-30

Tags: components, fasteners, rivet-nuts, threaded-inserts

Böllhoff's hexagonal steel **RIVKLE 233 41 060 030** lists **M6**, **0.5–3.0 mm** grip, **15.7 mm** body length and a **9.0 +0.1/0 mm** hexagonal hole across flats. GESIPA's half-hexagonal A2 **1455460** also lists M6, but has **15.5 mm** body length and an **SW9 +0.1** hole field. Use the exact mounting drawing, grip range and setting conditions for each product. [catalogue's steel flat-head hexagonal open table, p. 17](https://media.boellhoff.com/files/pdf13/rivkle-blind-rivet-nuts-and-studs-en-2307.pdf#page=17), [article-specific technical specifications](https://en.gesipa.de/products/standard-blind-rivet-nuts/1455460-blind-rivet-nuts-stainless-steel-a2-half-hexagonal-small-head-m-6-x-9-x-155/).

## Scope and mechanism

A blind rivet nut installs an internal thread in a thin host with setting access from one side. [GESIPA, Blind rivet nuts](https://www.gesipa.com/products/blind-rivet-nuts/).

RIVKLE setting forms a bead from the shank behind the sheet. The head and bead grip opposite faces. [Böllhoff, RIVKLE method and principle](https://www.boellhoff.com/de-en/products/special-fasteners/rivkle-blind-rivet-nuts-and-blind-rivet-studs/).

Use the exact product’s installation and performance evidence for the actual host.

## Geometry and product identity

| Feature | Distinction |
| --- | --- |
| Head | GESIPA describes a flat head as providing a large contact area; a small head reduces protrusion. A countersunk head corresponds to a countersunk hole. Those forms should not share an assumed seating geometry. |
| Shank | Round, knurled, hexagonal and square are distinct GESIPA options. A polygonal body is not merely a round body with a different nominal diameter. |
| Host material | GESIPA offers steel, aluminium and stainless-steel nuts. The insert material designation does not identify the host-sheet material. |

The head, shank and material descriptions above come from [GESIPA, construction of a blind rivet nut](https://www.gesipa.com/products/blind-rivet-nuts/).

Böllhoff separately lists smooth round, knurled round, hexagonal and partial-hexagonal RIVKLE shanks. It identifies hexagonal geometry as resisting rotation. Its standard range includes open and closed ends; the closed version adds protection against dirt and moisture. A closed end alone is not evidence of a qualified seal at the head-to-sheet interface: Böllhoff identifies Seal Ring as a separate product technology. [Böllhoff, Standard and Seal Ring variants](https://www.boellhoff.com/de-en/products/special-fasteners/rivkle-blind-rivet-nuts-and-blind-rivet-studs/)

## Grip, hole and clearance dimensions

Böllhoff's catalogue legend defines **grip range** as the total thickness retained, including a multilayer workpiece. It distinguishes thread size, overall length, head size and hole geometry. A round hole uses diameter; a hexagonal hole uses width across flats. Setting stroke is the change in overall length. The listed blind-side projection is a clearance quantity, explicitly unsuitable as a quality-control criterion. [RIVKLE catalogue, p. 13](https://media.boellhoff.com/files/pdf13/rivkle-blind-rivet-nuts-and-studs-en-2307.pdf#page=13)

The following examples retain each source's dimensions and terminology; they are not a cross-brand substitution table.

| Named part and source | Body, head and end | Selected dimensions in that source |
| --- | --- | --- |
| Böllhoff RIVKLE `233 41 060 030` | Steel, hexagonal, flat head, open | M6; grip 0.5–3.0 mm; length 15.7 mm; head diameter 12.9 mm; hexagonal hole `H = 9.0 +0.1/0 mm` across flats. |
| GESIPA article `1455460` | Stainless steel A2, material No. 1.4567; half-hexagonal, small head | M6; body length 15.5 mm; head diameter 10.40 mm; thread length 8.00 mm. Hole field is published as `SW9 + 0,1`. |

The RIVKLE row is from the [catalogue's steel flat-head hexagonal open table, p. 17](https://media.boellhoff.com/files/pdf13/rivkle-blind-rivet-nuts-and-studs-en-2307.pdf#page=17). The GESIPA row is from its [article-specific technical specifications](https://en.gesipa.de/products/standard-blind-rivet-nuts/1455460-blind-rivet-nuts-stainless-steel-a2-half-hexagonal-small-head-m-6-x-9-x-155/). The latter is HTML product data, not an inspected controlled drawing; its `SW` hole field must not be read as a round drill diameter. Neither row establishes interchangeability, finished-hole process capability or an accepted joint load.

## Setting, rotation and failure terminology

Sherex's catalogue distinguishes rivet-nut test results by failure mode and fixture:

| Term in Sherex's testing methods | What it measures |
| --- | --- |
| Spin out | Torque that makes the installed nut rotate in its hole. |
| Torque out | Thread-stripping torque with the nut head trapped between a nonrotating mating part and the base panel. This fixture suppresses spin-out. |
| Pull out | Axial failure through thread extraction, or through base-material distortion allowing the complete nut to pull through. |
| Suggested assembly torque | An assembly recommendation associated with Class 8.8/Grade 5 hardware, rather than a setting-force specification. |

Sherex also identifies cross-threading, corrosion-induced binding and locking-screw prevailing torque exceeding spin-out resistance as possible spin-out causes. It warns that friction, finish and washers affect torque and calls for application testing. Thus antirotation geometry is only one part of the joint definition; thread-stripping torque cannot substitute for rotation resistance. [Sherex, C-RN 5/2017, printed p. 47 / PDF p. 49](https://fasteners.sherex.com/Asset/Rivet-Nut-Catalog.pdf#page=49)

## Reading catalogue performance conditions

Masterfix's October 2024 catalogue describes typical results from representative samples, not guaranteed performance of every application:

1. Applied-torque testing uses a mating test screw and a steel top plate restrained from rotating. Its torque column is the maximum recommended torque applied to the mating screw.
2. Pull-out testing uses steel plates at the particular nut's maximum grip thickness.
3. Single-shear testing uses hardened steel plates at maximum grip; the reported strength concerns the nut and excludes the mating screw.

The catalogue states that the application's material or screw may be weaker and recommends testing the actual joint. [Masterfix, printed p. 47 / PDF p. 24](https://res.cloudinary.com/syndigo-sbd-ps/image/upload/q_auto/Stanley%20Engineered%20Fastening%20%28SEF%29/Public/sef-resources/library/user-manuals-and-documentation/Masterfix_Catalogue_Final_Small_Size.pdf#page=24)

Its `23-CO` series, for example, is steel, zinc plated, open ended and cylindrical headed. That description does not identify a stainless, closed-end or hex-body equivalent. The same catalogue distinguishes the EPDM MFX Rubnut, which deforms during mating-screw tightening, from tool-set metal rivet nuts. [Masterfix, printed pp. 48–49 / PDF p. 25](https://res.cloudinary.com/syndigo-sbd-ps/image/upload/q_auto/Stanley%20Engineered%20Fastening%20%28SEF%29/Public/sef-resources/library/user-manuals-and-documentation/Masterfix_Catalogue_Final_Small_Size.pdf#page=25)

## Application-specific coverage limits

Explanatory synthesis: the cited dimensions describe named combinations of thread, head, body, end form and material with a particular grip range and mounting-hole geometry. They do not establish interchangeability with other parts or a complete specification for an unspecified joint. [RIVKLE catalogue, steel hexagonal examples, p. 17](https://media.boellhoff.com/files/pdf13/rivkle-blind-rivet-nuts-and-studs-en-2307.pdf#page=17)

Masterfix's installed-nut results cover the stated mating-screw, plate and maximum-grip test conditions. They do not establish performance for a different host material, retained thickness or screw pairing. Application-specific setting controls, finished-hole quality and accepted service loads are outside the evidence presented here. [Masterfix, printed p. 47 / PDF p. 24](https://res.cloudinary.com/syndigo-sbd-ps/image/upload/q_auto/Stanley%20Engineered%20Fastening%20%28SEF%29/Public/sef-resources/library/user-manuals-and-documentation/Masterfix_Catalogue_Final_Small_Size.pdf#page=24)

No full ISO, DIN or aerospace standard was reviewed for this draft. Catalogue references to standards do not establish compliance of an unspecified joint.

## Source editions and review limits

Review and retrieval date: **2026-10-30 PDT (America/Los_Angeles)**. This is distinct from publication date. Only the cited sections and product rows support this draft; neither complete catalogue coverage nor a current controlled engineering drawing is claimed.

- **Böllhoff RIVKLE, Blind rivet nuts and studs:** printed document code `2307/21-V1-EN (BOF) 99900000027/00`, back cover / PDF p. 68. Cited geometry and dimensional pages were visually inspected. Exact publication day is unstated. [Catalogue and document identifier](https://media.boellhoff.com/files/pdf13/rivkle-blind-rivet-nuts-and-studs-en-2307.pdf#page=68)
- **Masterfix, Blind Rivets, Rivet Nuts & Tooling Catalogue:** back cover identifies `©2024` and `10.24`; cited printed pp. 47–49 and the back cover were visually inspected. Exact publication day is unstated. [Catalogue, PDF p. 41](https://res.cloudinary.com/syndigo-sbd-ps/image/upload/q_auto/Stanley%20Engineered%20Fastening%20%28SEF%29/Public/sef-resources/library/user-manuals-and-documentation/Masterfix_Catalogue_Final_Small_Size.pdf#page=41)
- **Sherex rivet-nut catalogue:** printed code `C-RN 5/2017`; testing-method page and back cover were visually inspected. This older edition supports terminology only, not current availability or current application values. [Catalogue, PDF p. 56](https://fasteners.sherex.com/Asset/Rivet-Nut-Catalog.pdf#page=56)
- **Böllhoff and GESIPA HTML pages:** revision/publication dates are unstated. Their retrieval date does not create a drawing revision. GESIPA's displayed torque and thread-breaking-force numbers are not reproduced because the inspected product page does not provide their full test conditions.

## Related reference

[Hardware and component references](../index.md) provides adjacent process context; it does not qualify the products or assemblies discussed here.