---
title: "What Are All-Metal Prevailing Torque Hex Lock Nut (Type 1) Used For?"
description: "All-Metal Prevailing Torque Hex Lock Nut (Type 1) (GB/T 6184 / ISO 7042) are used for the clamped counter-face of a bolted joint. Catalogued M3 to M36."
url: https://engineeringhardware.com/applications/cad-svg-047-nylocnut/
source: Engineering Hardware & Fasteners
---

# What Are All-Metal Prevailing Torque Hex Lock Nut (Type 1) Used For?

Nuts · GB/T 6184 / ISO 7042 · Application guide

Typical applications, the industries that specify all-metal prevailing torque hex lock nut (type 1), and how to choose the right size, material and finish for the joint.

All-Metal Prevailing Torque Hex Lock Nut (Type 1) are used for the clamped counter-face of a bolted joint. They are manufactured to GB/T 6184 / ISO 7042, and the choice of size, property class and finish is driven by the load in the joint and the environment it sits in.

- **Primary duty:** The clamped counter-face of a bolted joint
- **Governing standard:** GB/T 6184 / ISO 7042
- **Thread size range:** M3 to M36
- **Category:** Nuts

Application notes are general engineering guidance. Verify the property class and any approval requirement against your own design calculation.

![What Are All-Metal Prevailing Torque Hex Lock Nut (Type 1) Used For? application image](https://engineeringhardware.com/wp-content/uploads/2026/06/108-All-Metal-Prevailing-Torque-Hex-Lock-Nut-Type-1-—-GB／T-6184-／-ISO-7042-Series-047-—-GB／T-6184-／-ISO-7042.webp)

All-Metal Prevailing Torque Hex Lock Nut (Type 1) are selected when an assembly calls for the clamped counter-face of a bolted joint. This application guide to the GB/T 6184 / ISO 7042 type covers concrete end-uses, the specification checklist, correct installation, and where an alternative fastener performs better. Stocked across roughly M3 to M36, they cover general to heavy-duty work.

## Typical Applications for All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047)

The most common settings where these are specified:

- **Bolted joints:** the clamping counter-face on studs and bolts across every assembly type.
- **Vibration-prone equipment:** where a locking or flanged style resists loosening.
- **Frames & weldments:** captive or welded options for repeatable assembly.
- **General machine building:** fastening covers, brackets, motors and sub-assemblies on production equipment.
- **Maintenance & repair (MRO):** a stocked size for servicing existing plant where the original fastener spec must be matched.

## How to Specify All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047) for Your Application

- **Size:** Match the nominal size to the mating thread or hole. This product spans M3–M36; check the full table below for the exact dimensions of each size.
- **Locking & grade:** Match the strength grade to the bolt, and choose a locking style (nyloc, all-metal, serrated flange) if the joint sees vibration.
- **Environment:** For damp, coastal or chemical exposure prefer A4/316 stainless or a suitable coating; indoors, plated steel or A2 is usually sufficient.
- **Standard:** This product is supplied to GB/T 6184 / ISO 7042. Quoting the standard on your order guarantees interchangeable dimensions between suppliers.

## Installation & Assembly Practice

- Run the nut down by hand before applying the wrench to catch cross-threading early.
- Tighten the nut rather than the bolt head where access allows — the torque-to-preload relation is more consistent.
- For locking styles, note that nyloc inserts are single-use in critical joints and lose grip above roughly 120 °C.

## Common Selection Mistakes with All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047)

- Pairing a high-class bolt with a lower-class nut — the nut strips before the bolt reaches proof load; the nut class must meet or exceed the bolt class.
- Using a plain nut with a spring washer in severe vibration instead of a prevailing-torque locking nut.
- Re-using nyloc nuts in critical joints.

## Where All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047) Are Not the Right Choice

Not on their own — they need a matching bolt or stud — and a plain nut is not a substitute for a locking type under heavy vibration.

Custom manufacturing · Made to drawing

## Need a all-metal prevailing torque hex lock nut (type 1) outside the standard range?

Locking method is specifiable independently of the rest: nylon insert, all-metal deformed thread, serrated flange, or none. Made by cold heading or tapping.

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

[Custom nut manufacturing](https://engineeringhardware.com/custom/nuts/)[Send a drawing](https://engineeringhardware.com/custom/nuts/#rfq)

## Technical Drawing

Dimensioned line drawing of M3 All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047) to GB/T 6184 / ISO 7042. Side view and top view, drawn to the dimensions in the table below and redrawn for any size selected.

- **Pitch (mm):** 0.5
- **Width across flats s (mm):** 5.5
- **Width across corners e (mm):** 6.01
- **Total height m (mm):** 4.0

## Dimensions & Specifications (GB/T 6184 / ISO 7042)

| Size | Pitch (mm) | Width across flats s (mm) | Width across corners e (mm) | Total height m (mm) | Reference standard |
| --- | --- | --- | --- | --- | --- |
| M3 | 0.5 | 5.5 | 6.01 | 4.0 | ISO 7040 / DIN 985 |
| M4 | 0.7 | 7.0 | 7.66 | 5.0 | ISO 7040 / DIN 985 |
| M5 | 0.8 | 8.0 | 8.79 | 5.0 | ISO 7040 / DIN 985 |
| M6 | 1.0 | 10.0 | 11.05 | 6.0 | ISO 7040 / DIN 985 |
| M8 | 1.25 | 13.0 | 14.38 | 8.0 | ISO 7040 / DIN 985 |
| M10 | 1.5 | 16.0 | 17.77 | 10.0 | ISO 7040 / DIN 985 |
| M12 | 1.75 | 18.0 | 20.03 | 12.0 | ISO 7040 / DIN 985 |
| M14 | 2.0 | 21.0 | 23.36 | 14.0 | ISO 7040 / DIN 985 |
| M16 | 2.0 | 24.0 | 26.75 | 16.0 | ISO 7040 / DIN 985 |
| M18 | 2.5 | 27.0 | 30.14 | 18.0 | ISO 7040 / DIN 985 |
| M20 | 2.5 | 30.0 | 33.53 | 20.0 | ISO 7040 / DIN 985 |
| M24 | 3.0 | 36.0 | 39.98 | 22.0 | ISO 7040 / DIN 985 |
| M30 | 3.5 | 46.0 | 50.85 | 25.0 | ISO 7040 / DIN 985 |
| M36 | 4.0 | 55.0 | 60.79 | 29.0 | ISO 7040 / DIN 985 |

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](https://engineeringhardware.com/wp-content/uploads/2026/08/09-wire-rod-feed-cold-heading-machine.webp) 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](https://engineeringhardware.com/wp-content/uploads/2026/08/03-thread-rolling-machine-bolt-production.webp) 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](https://engineeringhardware.com/wp-content/uploads/2026/08/05-heat-treatment-baskets-black-bolts.webp) 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](https://engineeringhardware.com/wp-content/uploads/2026/08/23-zinc-plated-bolts-treatment-basket.webp) 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

### Do All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047) need a locking feature?

If the joint sees vibration or cyclic load, use a locking style (nyloc, all-metal lock, or serrated flange) or a thread-locking adhesive. For static joints a standard nut tightened correctly is usually sufficient.

### What material should All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047) be for outdoor use?

For damp, coastal or chemical environments specify A4 (316) stainless or a suitably coated steel. For indoor or dry use, A2 (304) stainless or zinc-plated steel is normally adequate.

### Are All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047) made to a recognized standard?

Yes — they are manufactured to GB/T 6184 / ISO 7042, so dimensions are interchangeable between suppliers when you quote the standard on your order.

### What are All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047) used for?

The clamped counter-face of a bolted joint. They are supplied to GB/T 6184 / ISO 7042.

### Can I get a quote for All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047) in the size and material I need?

Yes. Use the technical drawing and quote form on this page to set the size and options, then send the exact configuration to our team for pricing and lead time.

## Related Pages

Product page: [All-Metal Prevailing Torque Hex Lock Nut (Type 1) — GB/T 6184 / ISO 7042 (Series 047) — specifications & sizes](https://engineeringhardware.com/fastener/cad-svg-047-nylocnut/)

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