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Nuts · Trade series (Bollhoff RIVKLE stainless-steel series)

A2 (304) Stainless Steel Stainless Knurled Countersunk Blind Rivet Nuts

Mechanical properties, corrosion behaviour and the full dimensional range for this grade.

A2 Stainless Steel Stainless Knurled Countersunk Blind Rivet Nuts are supplied to ISO 3506 group A2 (304 / 1.4301), commonly supplied A2-70. Corrosion behaviour is good general corrosion resistance, the material is largely non-magnetic, and the usable service range is approx. -200 °C to +400 °C, subject to the property class and the joint. In practice this grade is the most common stainless group for indoor and general outdoor fasteners.

Grade
ISO 3506 group A2 (304 / 1.4301), commonly supplied A2-70
Corrosion resistance
Good general corrosion resistance
Magnetic response
Largely non-magnetic
Service temperature
approx. -200 °C to +400 °C, subject to the property class and the joint

Property values are typical for the grade. Certified mechanical test data is available on request for production orders.

A2 (304) Stainless Steel Stainless Knurled Countersunk Blind Rivet Nuts reference image

A2 Stainless Steel Stainless Knurled Countersunk Blind Rivet Nuts are supplied to Trade series (Bollhoff RIVKLE stainless-steel series). The grade provides good general corrosion resistance and is largely non-magnetic; the practical service range is approx. -200 °C to +400 °C, subject to the property class and the joint. Property data, grade comparison and the full size table follow.

Why Choose A2 Stainless Steel for Stainless Knurled Countersunk Blind Rivet Nuts

The most common stainless group for indoor and general outdoor fasteners. For stainless knurled countersunk blind rivet nuts, this matters when good general corrosion resistance is the primary requirement.

Mechanical & Physical Properties

Grade designationISO 3506 group A2 (304 / 1.4301), commonly supplied A2-70
Magnetic responseLargely non-magnetic
Service temperatureapprox. -200 °C to +400 °C, subject to the property class and the joint
Corrosion characteristicGood general corrosion resistance

Corrosion Behavior in Service

A2 (304) gives excellent atmospheric and most-water corrosion resistance and is the most common stainless for Stainless Knurled Countersunk Blind Rivet Nuts in indoor and general outdoor service. In chloride-bearing environments (marine air, road salt, swimming pools) consider stepping up to A4 (316).

Galvanic & Galling Considerations

Two important notes for stainless stainless knurled countersunk blind rivet nuts: (1) stainless can gall on stainless threads under load — use a thread lubricant or anti-galling compound, especially for M6 and below; (2) when joined to aluminum or galvanized steel, stainless can drive galvanic corrosion of the less-noble metal in wet service — isolate with a coating or sleeve where appropriate.

Using Stainless Fasteners in Aluminum

Stainless steel is more noble than aluminum, so in the presence of an electrolyte — rain, condensation, salt spray — the aluminum becomes the anode and corrodes at the joint. The effect is driven by the area ratio: a small stainless fastener in a large aluminum section is normally acceptable, while a large stainless fastener in thin aluminum is not. Where the joint is wet, isolate the two metals with a coated or nylon washer and a sealant, or specify an aluminum or coated fastener instead.

Sizes of Stainless Knurled Countersunk Blind Rivet Nuts Available in A2 Stainless Steel

Thread sizeBody diameter (mm)Body length (mm)Grip range (mm)Hole diameter (mm)Countersink thickness (mm)End options
M38.87.01.3~2.05.00.9open / closed
M39.97.02.0~3.05.00.9open / closed
M49.38.01.3~2.06.00.9open / closed
M410.38.02.0~3.06.00.9open / closed

Technical Drawing

Customize the parameters below — every spec field is editable, and the drawing redraws to match the values you choose. Changing the size will snap the other fields to that size's standard values; you can then override any individual value.

Sends the selected values to the quote form below.

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The form below follows the current technical drawing configuration. Change the drawing values above and the request details update automatically.

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Specification
Business Information

Dimensions & Specifications (Trade series (Bollhoff RIVKLE stainless-steel series))

Thread sizeBody diameter (mm)Body length (mm)Grip range (mm)Hole diameter (mm)Countersink thickness (mm)End options
M38.87.01.3~2.05.00.9open / closed
M39.97.02.0~3.05.00.9open / closed
M49.38.01.3~2.06.00.9open / closed
M410.38.02.0~3.06.00.9open / closed

Applications & Industries

Where Stainless Knurled Countersunk Blind Rivet Nuts are used, and what decides the specification in each case. Stocked from M3 to M4.

Industries that specify Stainless Knurled Countersunk Blind Rivet Nuts

  • Automotive interiors Flush threaded mounting points behind trim and finished panels.
  • Laboratory equipment Stainless blind threads in cleanable covers and guards.
  • Electronic housings Serviceable threads in thin sheet where insert rotation must be controlled.
  • Precision fabrication Countersunk blind inserts that remain below the finished panel face.
  • Automotive & transport Vibration-prone joints where the locking type is specified on the drawing.
  • Maintenance & MRO Replacements matched to the existing bolt class, thread and finish.

Typical applications

  • leaving a countersunk insert flush with the parent sheet
  • resisting rotation through a knurled blind body
  • adding a reusable thread without reaching the rear of the panel
  • matching countersink depth, hole diameter and grip range
  • locking an adjustment so it cannot drift
  • joints re-torqued at a service interval

Service conditions to specify against

Marine and coastal
Available in A4 (316) stainless for chloride exposure — coastal structures, pool halls, water treatment and deck hardware, where A2 will eventually pit.
High load
Supplied in ISO 898-1 property classes, so the joint can be designed to a stated proof load and tightened to a calculated torque rather than by feel.
Match the class
A nut below the bolt property class strips before the bolt reaches its own limit — pair class 8 nuts with 8.8 bolts, class 10 with 10.9.

Where to use something else

  • Do not leave the countersink shallow; a proud flange can interfere with the mating panel or finish.

Full application guide: where Stainless Knurled Countersunk Blind Rivet Nuts are used, how to specify them, and the cases they are wrong for

Inside the plant

Manufactured in our own plant

This part is cold-formed, threaded, heat-treated and finished in-house. The stages below are where its class and finish are actually decided.

  1. Wire rod feeding into a cold heading machine
    01

    Cold heading

    Wire rod is drawn to size and cold-formed into blanks. Forming rather than cutting keeps the grain flow continuous around the head, which is where a bolt is most likely to fail.

    Head dimensions and under-head radius checked at set-up and per shift.

  2. Thread rolling machine producing bolt threads
    02

    Thread rolling

    Threads are rolled between hardened dies rather than cut. Rolled threads are stronger in fatigue than cut threads and hold pitch and flank angle far more consistently across a batch.

    Go / no-go ring gauges to ISO 965 tolerance class 6g.

  3. Baskets of bolts staged for heat treatment
    03

    Heat treatment

    Quench-and-temper brings carbon and alloy steel to the property class ordered — 8.8, 10.9 or 12.9 — with the furnace charge tracked so a finished lot can be traced back to it.

    Core hardness and tensile tested per lot to ISO 898-1.

  4. Zinc plated bolts in a treatment basket
    04

    Surface treatment

    Zinc, zinc-nickel, hot-dip galvanizing, black oxide, phosphate and Dacromet, selected against the service environment rather than against the price list.

    Coating thickness and neutral salt spray hours to ISO 9227.

Frequently Asked Questions

Can A2 Stainless Steel Stainless Knurled Countersunk Blind Rivet Nuts gall during installation?

Yes — stainless on stainless is prone to thread galling under load, especially at smaller sizes. Use an anti-galling lubricant or wax thread compound, and slow the tightening rate where possible.

Is A2 Stainless Steel food-grade?

A2 (304) is widely accepted for food contact in non-chloride environments; A4 (316) is preferred where chlorides are present.

Can A2 Stainless Steel Stainless Knurled Countersunk Blind Rivet Nuts be used with aluminum?

Yes, but stainless drives mild galvanic corrosion of aluminum in wet service — isolate with a coating, sleeve or paint, or accept the trade-off if the joint is dry and indoor.

What's the service temperature limit for A2 Stainless Steel?

The practical service range is approx. -200 °C to +400 °C, subject to the property class and the joint.

How do I request a quotation?

Use the technical drawing on this page to pick the exact configuration, then submit it with the quote form. We respond within one business day.