ASME B18.2.1 HEX BOLT — 5/16

ASME B18.2.1 HEX BOLT — 5/16: width across flats 12.29–12.7 mm, head height 4.95–5.97 mm, pitch 18 TPI. Material Grade 5, surface Plain, tensile strength 119,946 psi. Dimensional tolerances per ASME B18.

BOLTS

High-performance industrial fastener under ASME B18.2.1 standard.
CEV-1 HASH: 32bcf1a33107e8099e632efac74c678be30992848e941429c32e220f9103b148 · FROZEN: 2026-05-24 00:43:04 · ASSET: standard_map_core.csv

Material Grade Filter

Dimensions

Width Across Flats (F)12.29–12.7 mm
Head Height (H)4.95–5.97 mm
Pitch18 TPI
Tensile Strength119,946 psi
MaterialGrade 5
SurfacePlain

Dimensional tolerances per ASME B18.2.1-2012 (hex bolts) (inch series; values converted from inches).

Grades

Grade 5

Grade Grade 5 · Plain

Grade 5

Grade Grade 5 · Zinc

Grade 5

Grade Grade 5 · HDG

Grade 8

Grade Grade 8 · Plain

Grade 8

Grade Grade 8 · Zinc

Grade 8

Grade Grade 8 · HDG

← Back to ASME B18.2.1 HEX BOLT → B3 Grade Matrix → Engineering Center (C)

Need technical support?

Contact engineering team for verified B2 data reference.

Standard References: Official ASME standards · ASME B18.2.1 reference (fasteners.eu)

ASME B18.2.1 Hexagon Head Bolt per ASME B18.2.1 specification, available in Grade 5 grade with Plain finish. Engineered for industrial OEM applications requiring 827.0 MPa tensile strength and reliable long-term fastening performance.

💬

Frequently asked questions

What is the width across flats of ASME B18.2.1 HEX BOLT — 5/16?

12.29–12.7 mm (nominal with the tolerance range shown above)

What is the head height of ASME B18.2.1 HEX BOLT — 5/16?

4.95–5.97 mm (nominal with the tolerance range shown above)

What is the thread pitch of ASME B18.2.1 HEX BOLT — 5/16?

18 TPI

What material, finish and strength does this page list?

Material: Grade 5, surface: Plain, tensile strength: 119,946 psi.

Which tolerance basis is used on this page?

ASME B18.