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Seals · ISO / DIN

A4 (316) Stainless Steel O-Ring Seal

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

A4 Stainless Steel O-Ring Seal are supplied to ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80. Corrosion behaviour is superior, including marine and chloride environments, 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 specified for marine, coastal and chemical applications.

Grade
ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80
Corrosion resistance
Superior, including marine and chloride environments
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.

A4 (316) Stainless Steel O-Ring Seal reference image

A4 Stainless Steel is not a material o-ring seal are supplied in. O-Ring Seal are specified by inside diameter, and this combination does not describe a part that exists.

The materials that do apply are: NBR (Nitrile), FKM (Viton®-type), EPDM, Silicone (VMQ), PTFE.

See the O-Ring Seal product page for the specifications that do apply →

Custom manufacturing · Made to drawing

Need this seal in a grade that is not listed?

A4 Stainless Steel is one of the grades the catalog describes. Inside diameter, cross-section and compound are the three that matter, and the compound is chosen against the fluid and the temperature rather than the dimensions.

Minimum order from 2,000 pieces; samples within 7 days of drawing approval.

Custom seal manufacturingSend a drawing

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.

Dimensioned line drawing of 5 O-Ring Seal — ISO / DIN (Series 160). Side view and top view, drawn to the dimensions in the table below and redrawn for any size selected.
Outer diameter d2 (mm)
9
Wire dia (mm)
2
Material
NBR 70
Working temp range
-30 to +110 C
Sends the selected values to the quote form below.

Request a Quote

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

Request a Quotation

Specification
Business Information

Dimensions & Specifications (ISO / DIN)

Inner diameter d1 (mm)Outer diameter d2 (mm)Wire dia (mm)MaterialWorking temp rangeReference standard
592NBR 70-30 to +110 CISO 3601 / GB/T 3452
8122NBR 70-30 to +110 CISO 3601 / GB/T 3452
10163NBR 70-30 to +110 CISO 3601 / GB/T 3452
15213NBR 70-30 to +110 CISO 3601 / GB/T 3452
20263NBR 70-30 to +110 CISO 3601 / GB/T 3452
25334NBR 70-30 to +110 CISO 3601 / GB/T 3452
30384NBR 70-30 to +110 CISO 3601 / GB/T 3452
40505NBR 70-30 to +110 CISO 3601 / GB/T 3452
50605NBR 70-30 to +110 CISO 3601 / GB/T 3452
60726NBR 70-30 to +110 CISO 3601 / GB/T 3452
80926NBR 70-30 to +110 CISO 3601 / GB/T 3452
1001147NBR 70-30 to +110 CISO 3601 / GB/T 3452

Applications & Industries

O-Ring Seal are bought for a small number of well-defined jobs. These are the ones we ship them for. Stocked from 5 to 100 (inside diameter).

Industries that specify O-Ring Seal

  • Process & food equipment Sealing at joints that are cleaned and inspected.
  • Hydraulics & pneumatics Static and dynamic sealing in cylinders and valve bodies.

Typical applications

  • excluding dust and moisture from a housing
  • sealing a joint against fluid or air pressure

Service conditions to specify against

Sealed joints
Used where the fixing has to keep water or air out as well as hold — the elastomer, not the fastener, decides service life.

Need help matching O-Ring Seal to your application? Send the assembly, the load and the environment with your enquiry and we will specify the size, material and finish against them.

Video: A4 (316) Stainless Steel O-Ring Seal

Third-party video, selected automatically for this topic. It is not produced by Engineering Hardware and is not a specification source — use the tables on this page for dimensional data.

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 A4 Stainless Steel O-Ring Seal — ISO / DIN (Series 160) 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 A4 Stainless Steel food-grade?

A4 (316) is the standard food-contact stainless grade in most jurisdictions, particularly where chloride exposure (brines, dairy CIP) is present.

Can A4 Stainless Steel O-Ring Seal — ISO / DIN (Series 160) 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 A4 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.