WhatsAppSend RFQ
Menu
Home/Products/Bolts/Carriage Bolts/Carriage Bolt ASME B18.5

Carriage Bolt ASME B18.5

ASME B18.5 (Current)

Material
Carbon Steel
Property Class
Grade 5
Finish
Zinc Plated, Hot Dip Galvanized, Plain
Size range
1/4-20UNC–7/8-9UNC
Share

Select sizes and quantities — 114 confirmed sizes to ASME B18.5

Material
Grade
Finish
dNominal Diameter (in)lLength (in)TPIThreads Per InchThread SeriesThread ClassdBasic Major Diameter (in)MOQQuantity and inquiry
5/16-18 UNC1.2518UNC2A0.31251000
5/16-18 UNC1.37518UNC2A0.31251000
5/16-18 UNC1.518UNC2A0.31251000
5/16-18 UNC1.7518UNC2A0.31251000
5/16-18 UNC218UNC2A0.31251000
5/16-18 UNC2.2518UNC2A0.31251000
5/16-18 UNC2.518UNC2A0.31251000
5/16-18 UNC2.7518UNC2A0.31251000
5/16-18 UNC318UNC2A0.31251000
5/16-18 UNC3.2518UNC2A0.31251000
5/16-18 UNC3.518UNC2A0.31251000
5/16-18 UNC3.7518UNC2A0.31251000
5/16-18 UNC418UNC2A0.31251000
3/8-16 UNC1.12516UNC2A0.3751000
3/8-16 UNC1.2516UNC2A0.3751000
3/8-16 UNC1.37516UNC2A0.3751000

Showing 16 of 114 sizes

5/16-18 UNC × 1.25 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)1.25
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 1.375 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)1.375
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 1.5 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)1.5
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 1.75 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)1.75
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 2 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)2
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 2.25 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)2.25
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 2.5 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)2.5
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 2.75 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)2.75
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 3 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)3
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 3.25 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)3.25
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 3.5 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)3.5
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 3.75 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)3.75
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

5/16-18 UNC × 4 × 18 × UNC × 2A × 0.3125 × 0.324 × 0.272 × 0.719 × 0.688 × 0.176 × 0.156 × 0.324 × 0.307 × 0.187 × 0.156 × 0.031

dNominal Diameter (in)5/16-18 UNC
lLength (in)4
TPIThreads Per Inch18
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.3125
MOQ1000

3/8-16 UNC × 1.125 × 16 × UNC × 2A × 0.375 × 0.388 × 0.329 × 0.844 × 0.782 × 0.208 × 0.188 × 0.388 × 0.368 × 0.219 × 0.188 × 0.031

dNominal Diameter (in)3/8-16 UNC
lLength (in)1.125
TPIThreads Per Inch16
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.375
MOQ1000

3/8-16 UNC × 1.25 × 16 × UNC × 2A × 0.375 × 0.388 × 0.329 × 0.844 × 0.782 × 0.208 × 0.188 × 0.388 × 0.368 × 0.219 × 0.188 × 0.031

dNominal Diameter (in)3/8-16 UNC
lLength (in)1.25
TPIThreads Per Inch16
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.375
MOQ1000

3/8-16 UNC × 1.375 × 16 × UNC × 2A × 0.375 × 0.388 × 0.329 × 0.844 × 0.782 × 0.208 × 0.188 × 0.388 × 0.368 × 0.219 × 0.188 × 0.031

dNominal Diameter (in)3/8-16 UNC
lLength (in)1.375
TPIThreads Per Inch16
Thread SeriesUNC
Thread Class2A
dBasic Major Diameter (in)0.375
MOQ1000

Product details

Description
Inch round head carriage bolt manufactured to ASME B18.5. The bolt has a round head with a square neck under the head that resists rotation when seated in a square hole or timber. Threads are UNC series, class 2A, and the shank is threaded from the end up to the neck. Supplied in carbon steel Grade 5 with zinc plated, hot dip galvanized, or plain finish. Diameters range from 1/4-20 UNC to 1-8 UNC. For quotation, specify diameter, length, finish, and required quantity.
Features
Round head with square neck under the head to prevent rotation during tightening · Threaded over the full length up to the neck · UNC thread series, class 2A · Available in diameters 1/4-20 UNC through 1-8 UNC
Applications
Timber-to-metal connections in wood construction, Guardrail and fence assembly, Agricultural machinery and trailer bodies, Joints where the head must stay smooth and untouched by tools

Order assurance

Confirmed for the quoted product and order.

Reports & inspection

Agreed in the quotation.

  • EN 10204 3.1 material certificate
  • Dimensional inspection report
  • Certificate of conformity
  • Mechanical test report
  • Chemical analysis report
  • Coating inspection report
  • Batch and lot traceability

Packaging & delivery

Options we supply.

  • Bulk carton packing
  • Small boxes with outer cartons
  • Palletized shipment
  • Fumigation-free pallets
  • Inner poly bags
  • Buyer branding and labels

Product questions

What sizes of Carriage Bolt ASME B18.5 do you supply?

Execution standard: ASME B18.5. The confirmed specification table covers 1–7 diameters and 0.75–5.5 lengths. Use the specification table to select the exact variant required for quotation.

Which materials, grades and finishes can I order?

Material: Carbon Steel; Property class: Grade 5; Finish: Zinc Plated, Hot Dip Galvanized, Plain. Availability should be confirmed against the selected specification and order quantity.

Where are these carriage bolts typically used?

Typical applications include Timber-to-metal connections in wood construction, Guardrail and fence assembly, Agricultural machinery and trailer bodies, Joints where the head must stay smooth and untouched by tools. Final suitability depends on the selected material, grade, finish and operating conditions.

Related products

Hex Jam Nut ASME B18.2.2
Matching nominal sizes

Hex Jam Nut ASME B18.2.2

ASME B18.2.2 · 1/4-20UNC–7/8-9UNC

MOQ: 1000–5000 pcs
Hex Nut ASME B18.2.2
Matching nominal sizes

Hex Nut ASME B18.2.2

ASME B18.2.2 · 1/4-20UNC–7/8-9UNC

MOQ: 1000–5000 pcs
Step Bolt ASME B18.5
Same standard family

Step Bolt ASME B18.5

ASME B18.5 · 1/4-20UNC–7/16-14UNC

MOQ: 500–1000 pcs
Elevator Bolt ASME B18.5
Same standard family

Elevator Bolt ASME B18.5

ASME B18.5 · 1/4-20UNC–7/16-14UNC

MOQ: 500–1000 pcs
Hex Bolt, Fine Pitch, Partial Thread DIN 960
Same product family

Hex Bolt, Fine Pitch, Partial Thread

DIN 960 · M8–M24

MOQ: 100–300 pcs
T-Head Bolt DIN 261
Same product family

T-Head Bolt

DIN 261 · M8, M10, M12

MOQ: 200–500 pcs
Hexagon Flange Bolt with Serrated Flange DIN 6921
Same product family

Hexagon Flange Bolt with Serrated Flange

DIN 6921 · M5–M16

MOQ: 500–1000 pcs
Hexagon Head Bolt Partial Thread DIN 931
Same product family

Hexagon Head Bolt Partial Thread

DIN 931 · M6–M24

MOQ: 200–1000 pcs

Quote Carriage Bolt ASME B18.5

Add sizes, quantities, destination and any drawing or spreadsheet.

WhatsAppSend RFQ