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Washers · GB/T 5782 / ISO 4014

M18 General Flat Washer Dimensions & Specifications

M18 General Flat Washer Dimensions & Specifications reference image

The M18 size of General Flat Washer is dimensioned by GB/T 5782 / ISO 4014. The tables below give the dimensional row from the standard, the drill and spanner sizes that go with it, and the assembly torque per property class. The technical drawing on this page redraws to the exact values selected.

M18 Dimensional Row (GB/T 5782 / ISO 4014)

For bolt sizeInner diameter d1 (mm)Outer diameter d2 (mm)Thickness t (mm)Reference standard
M1819.034.03.0ISO 7089 / GB/T 97.1

Spanner & Drive for M18 General Flat Washer — GB/T 5782 / ISO 4014 (Series 008)

Drive geometry for M18 General Flat Washer — GB/T 5782 / ISO 4014 (Series 008) is given by the row above; match the tool to the listed values.

Common Applications for M18 General Flat Washer — GB/T 5782 / ISO 4014 (Series 008)

M18 General Flat Washer — GB/T 5782 / ISO 4014 (Series 008) are commonly specified for high-load load-spreading on structural joints.

Installation Tips for M18 General Flat Washer — GB/T 5782 / ISO 4014 (Series 008)

  • At M18 the stretch in the bolt becomes the controlling factor — for critical joints, use angle-controlled or stretch-controlled tightening instead of pure torque.

Mating Parts for M18

A M18 flat washer pairs with a M18 bolt/screw and matching M18 nut.

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.

Request a Quote

Adjust the parameters in the drawing above and click "Request this configuration" to send the exact specification straight to this form.

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Specification
Business Information

Dimensions & Specifications (GB/T 5782 / ISO 4014)

For bolt sizeInner diameter d1 (mm)Outer diameter d2 (mm)Thickness t (mm)Reference standard
M33.27.00.5ISO 7089 / GB/T 97.1
M44.39.00.8ISO 7089 / GB/T 97.1
M55.310.01.0ISO 7089 / GB/T 97.1
M66.412.01.6ISO 7089 / GB/T 97.1
M88.416.01.6ISO 7089 / GB/T 97.1
M1010.520.02.0ISO 7089 / GB/T 97.1
M1213.024.02.5ISO 7089 / GB/T 97.1
M1415.028.02.5ISO 7089 / GB/T 97.1
M1617.030.03.0ISO 7089 / GB/T 97.1
M1819.034.03.0ISO 7089 / GB/T 97.1
M2021.037.03.0ISO 7089 / GB/T 97.1
M2425.044.04.0ISO 7089 / GB/T 97.1
M3031.056.04.0ISO 7089 / GB/T 97.1
M3637.066.05.0ISO 7089 / GB/T 97.1

Frequently Asked Questions

What is the coarse-thread pitch of M18 for General Flat Washer — GB/T 5782 / ISO 4014 (Series 008)?

For M18 the standard coarse pitch is 2.5 mm — this is the value used for General Flat Washer — GB/T 5782 / ISO 4014 (Series 008).

What clearance and tapping drill suit M18?

Use a 20 mm clearance hole (ISO 273 medium) for through-fixing, or a 15.5 mm tapping drill for a coarse M18 thread.

Should M18 General Flat Washer — GB/T 5782 / ISO 4014 (Series 008) be tightened by torque or by angle?

For critical structural joints at M18, angle-controlled or stretch-controlled tightening is more repeatable than pure torque — the friction scatter at large diameters can dominate the torque signal.

What grip range is typical for M18 structural bolts?

Grip ranges are highly application-dependent at M18. As a guide, choose a length that gives at least 1× the thread diameter engagement in the nut plus 2–3 thread pitches projecting.

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.