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Blind Threaded Insert for Thin & Hollow Panels

Petal-Type Blind Rivet Nuts for Thin Panels

Petal expansion blind rivet nuts create a reusable internal thread in thin sheet metal, hollow panels and cavity structures where installation is possible from only one side. During setting, the slotted sleeve expands behind the panel to form multiple supporting legs and a wider rear bearing area.

  • M4, M5, M6 and M8 threads
  • One-sided blind installation
  • Wide rear-side expansion area
  • Carbon steel with zinc finish
  • Multiple sleeve lengths available
  • Samples, bulk supply and OEM packaging
Product Specification Snapshot
Product Type
Petal-Type Blind Rivet Nuts for Thin Panels
Thread Sizes
M4 / M5 / M6 / M8
Material
Carbon Steel
Surface Finish
Zinc Galvanized
Sleeve OD Range
8–15 mm
Installation
One-Sided Blind Setting
Typical Substrates
Thin metal, plastic and hollow panels
Exact hole diameter, panel thickness compatibility and grip range depend on the selected configuration. Confirm dimensions against the production drawing before volume ordering.
Blind Access Installed from one side
Petal Expansion Wide rear bearing area
M4–M8 Metric thread range
B2B Supply Samples to repeat orders
Why This Fastener

Designed for Thin and Hollow Substrates

  • Creates a reusable female thread in thin panels
  • Does not require access to the rear side during installation
  • Expanded legs distribute contact over a wider rear-side area
  • Useful where conventional nut-and-bolt fastening is impractical
  • Suitable for production assembly and maintenance applications
Product Overview

What Are Petal-Type Blind Rivet Nuts?

A petal expansion blind rivet nut is a threaded insert designed to provide an internal metric thread in materials that are too thin, hollow or difficult to access for a conventional nut.

Unlike a standard bolt-and-nut connection, installation takes place entirely from the accessible side of the workpiece. As the insert is set, the slotted sleeve deforms outward behind the panel and forms multiple petal-shaped supporting legs.

This expanded structure increases the contact area on the rear side of the substrate and is particularly useful in thin sheet-metal housings, hollow panels, plastic components, equipment covers, lighting assemblies and other lightweight structures.

DISLAB PRECISION supplies M4, M5, M6 and M8 petal rivet nuts with multiple overall lengths, sleeve lengths and body diameters for international industrial buyers, distributors and OEM sourcing projects.

Petal expansion blind rivet nut with a zinc-finished carbon steel body and threaded insert
Petal expansion blind rivet nut with a threaded insert, wide rear bearing area and zinc-finished carbon steel body.
Working Principle

How Does a Petal Rivet Nut Work?

The insert changes from a narrow sleeve into a broad rear-side support structure during installation.

01

Insert Into the Hole

Place the rivet nut through the correctly prepared mounting hole from the accessible side of the panel.

02

Set the Rivet Nut

A compatible installation tool pulls the threaded section toward the flange while the front of the insert remains seated against the panel.

03

Petals Expand Behind the Panel

The slotted sleeve opens into multiple legs behind the substrate, creating a wider bearing surface and a permanent threaded mounting point.

Installation sequence showing a petal expansion blind rivet nut inserted, set and expanded behind a panel
Installation sequence: insert the rivet nut, set the threaded mandrel and expand the sleeve behind the panel.
Technical Data

Petal-Type Blind Rivet Nut Specifications

Available dimensions cover multiple thread sizes and sleeve configurations. Final selection should be based on the actual mounting hole, panel thickness and assembly requirements.

Parameter Available Specification Selection Note
Thread Size M4, M5, M6, M8 Match the mating screw and required assembly size.
Nominal Length 20, 25, 27, 30, 39, 44, 45, 48, 53, 59, 60, 67, 73, 87, 88 mm Select according to the fastener configuration and substrate.
Sleeve Length 16, 17.5, 20, 21, 32, 37, 38, 46, 52, 60, 65, 80 mm Must be matched to panel thickness and required expansion geometry.
Sleeve Outer Diameter 8, 10, 12, 14, 15 mm Confirm the required mounting hole before production.
Material Carbon Steel Contact us if a specific material specification is required.
Surface Treatment Zinc Galvanized Finish Suitable finish should be selected according to the service environment.
Structural Options Petal expansion type / hollow-wall tight-locking type Structure should be selected according to substrate and installation space.

Important: The values above describe the available dimensional range and should not be interpreted as a one-to-one size combination. Exact thread size, sleeve diameter, length, hole diameter and grip range should be confirmed for the selected model.

Engineering Selection

How to Choose the Right Petal Rivet Nut

For accurate model selection, do not choose the fastener by thread diameter alone. Several application dimensions should be reviewed together.

01 · Thread Size

Confirm the Mating Screw

Choose M4, M5, M6 or M8 according to the mating screw, assembly layout and fastening requirement.

02 · Panel Thickness

Measure the Actual Substrate

Provide the sheet or panel thickness so that the sleeve geometry can be matched to the material being fastened.

03 · Hole Diameter

Match the Mounting Hole

Hole diameter affects seating and installation stability. Provide the existing hole size when replacing another insert.

04 · Substrate

Identify the Panel Material

Thin steel, aluminum, plastic, composite and hollow panels can behave differently during installation and should be evaluated separately.

05 · Sleeve Geometry

Check Available Rear Space

Confirm that the selected sleeve has sufficient room to expand behind the panel without interference from nearby components.

06 · Assembly Requirement

Define the Required Performance

For load-sensitive applications, provide pull-out, torque, vibration or other test requirements before mass production.

For faster size matching: send DISLAB PRECISION your thread size, panel material, panel thickness, hole diameter, available rear clearance, required quantity and any mechanical test requirements.
Application Guide

Where Are Petal Expansion Rivet Nuts Used?

These blind threaded inserts are mainly selected for thin, hollow or lightweight structures where conventional backside nut access is difficult or impossible.

Hollow Structures

Construction & Hollow Panels

Suitable for hollow-wall assemblies, decorative panels, lightweight brackets, ceiling-related mounting structures and other applications requiring a reusable threaded connection from one accessible side.

Thin Sheet Metal

Equipment & Metal Enclosures

Used in electrical cabinets, HVAC casings, equipment covers, sheet-metal housings and similar fabricated assemblies where the sheet is not thick enough for direct threading.

Lightweight Components

Automotive & Lighting Assemblies

Applicable to selected brackets, lighting housings, lamp assemblies and lightweight metal structures that require blind installation and a detachable screw connection.

Non-Metal Panels

Plastic & Composite Panels

The wider rear-side expansion area can be useful for applications involving selected plastic, composite and other lightweight panels. Sample installation is recommended before volume production.

Petal expansion blind rivet nut applications in thin sheet metal, hollow panels, electrical enclosures and lighting panels
Typical applications include thin sheet metal, hollow panels, electrical enclosures and lighting or plastic panels.
Fastener Comparison

Petal Rivet Nut vs. Standard Blind Rivet Nut

Both products create a threaded connection from one side, but the way they deform behind the panel is different.

Feature Petal Expansion Rivet Nut Conventional Blind Rivet Nut
Installation Access One-sided installation One-sided installation
Rear-Side Formation Slotted sleeve expands into multiple supporting legs Body typically deforms locally behind the panel
Rear Bearing Area Relatively broad expanded contact area Depends on body style and deformation design
Thin / Hollow Panels Designed specifically for these applications Suitability depends on rivet nut type and panel condition
Soft or Lightweight Panels Wide expansion may help distribute contact Requires careful model selection
Selection Requirement Hole size, thickness and expansion clearance must be checked Hole size and grip range must be checked

Fastener performance depends on the exact insert geometry, substrate material, panel thickness, mounting hole and installation setting. Sample validation is recommended for critical applications.

Installation Guide

How to Install Petal-Type Blind Rivet Nuts

Correct hole preparation and controlled setting are important for achieving consistent expansion behind the panel.

Recommended Installation Sequence

  1. Confirm the rivet nut model, thread size and panel thickness.
  2. Prepare the mounting hole according to the selected product drawing.
  3. Insert the rivet nut through the hole from the accessible side.
  4. Connect the insert to a compatible rivet-nut installation tool.
  5. Apply the appropriate setting movement so the sleeve expands behind the panel.
  6. Remove the tool and visually inspect the flange and rear-side expansion where accessible.
  7. Install the mating screw and confirm assembly fit before production release.

Common Installation Problems

  • Mounting hole diameter is too large
  • Selected sleeve geometry does not match panel thickness
  • Insufficient clearance behind the panel
  • Incorrect installation tool or mandrel
  • Insufficient setting movement
  • Excessive setting force or over-compression
  • Insert rotates after installation
  • Petal legs do not expand evenly
  • Mating screw thread does not match the insert
If you are replacing an existing fastener, send a photo together with thread size, hole diameter and panel thickness for faster identification.
B2B Industrial Supply

Petal Rivet Nuts for OEM, Distribution and Repeat Production

DISLAB PRECISION supports international industrial buyers sourcing petal expansion rivet nuts, blind threaded inserts and related fastening components.

Projects can begin with specification review and sample verification, followed by mixed-size purchasing, repeat production or bulk supply according to the buyer’s sourcing requirements.

Sample Verification Confirm fit and installation before volume orders.
Dimension Inspection Thread fit, sleeve size and overall dimensions can be checked.
Mixed-Size Supply Support sourcing projects involving multiple metric sizes.
Bulk Orders Suitable for repeat industrial and distribution requirements.
OEM Packaging Neutral and customized packing options can be discussed.
Specification Matching Selection support based on panel, hole and thread data.
Frequently Asked Questions

Petal-Type Blind Rivet Nut FAQ

Common questions from industrial buyers about selection, installation and purchasing.

What is a petal expansion blind rivet nut?
A petal expansion blind rivet nut is a threaded insert that can be installed from one side of a thin or hollow panel. During setting, its slotted sleeve expands behind the panel into several supporting legs, creating a reusable internal thread.
What thread sizes are available?
The current product range includes M4, M5, M6 and M8 metric threads. Multiple nominal lengths, sleeve lengths and sleeve outer diameters are available. Exact dimensional combinations should be confirmed before ordering.
What materials can petal rivet nuts be installed into?
Typical applications include thin sheet metal, selected plastic panels, aluminum housings, hollow panels and other lightweight structures. Suitability should be verified according to the actual material thickness and installation condition.
How do I select the correct rivet nut size?
Start with the required thread size, then confirm panel material, panel thickness, mounting hole diameter and available rear-side expansion space. For load-sensitive assemblies, also provide pull-out, torque or vibration requirements.
What hole diameter do I need?
Hole diameter depends on the selected sleeve outer diameter and product configuration. It should be confirmed against the specific product drawing rather than selected from thread size alone.
Can petal rivet nuts be used in very thin sheet metal?
Petal expansion rivet nuts are designed for thin and hollow structures, but the correct sleeve geometry must still be matched to the actual sheet thickness. Sample installation is recommended when the substrate is especially thin.
What is the difference between a petal rivet nut and a standard rivet nut?
The main difference is the rear-side deformation pattern. A petal rivet nut uses a slotted sleeve that opens into multiple supporting legs, while many conventional rivet nuts create a more localized deformation behind the workpiece. The best option depends on substrate, thickness, hole size and mechanical requirements.
Can I order samples before bulk purchasing?
Yes. Sample verification is recommended when confirming a new panel thickness, mounting hole, substrate material or assembly condition before repeat production.
Can DISLAB PRECISION provide custom sizes or OEM packaging?
Custom configuration and packaging requirements can be reviewed according to quantity and project specifications. Send the required thread size, dimensions, substrate information, quantity and packaging requirements for evaluation.
What information should I send when requesting a quote?
For efficient quotation, provide thread size, panel material, panel thickness, mounting hole diameter, preferred sleeve dimensions, surface-finish requirement, order quantity, packaging requirements and any applicable mechanical test requirements.
Technical Resource

Learn More About Industrial Fasteners

Compare common bolts, nuts, rivets, anchors and other fastening systems in our mechanical fastener selection guide.

Read the Fastener Guide
Request a Quote

Need Help Selecting Petal-Type Blind Rivet Nuts?

Send your application information to DISLAB PRECISION. Providing the key dimensions below helps us review the required configuration more efficiently.

Thread Size Panel Material Panel Thickness Hole Diameter Required Quantity Surface Finish Drawing / Photo