What are the product marking requirements for bolts?

Headed bolts are required to be stamped on top of the head, while most rods and some bent bolts are required to be stamped on one end.

This Fastener Identification Markings Chart shows the various marking requirements for most common grades of ASTM and SAE fasteners.

B7 Hex Head BoltHeaded Bolts

ASTM specifications require a manufacturer’s identification and ASTM grade to be permanent and either raised or indented. Fastener specification SAE J429 requires a manufacturer’s identification and nothing else on Grade 2, 3 radial lines on grade 5, and 6 radial lines on grade 8.

ASTM F1554 headed anchor bolts are the exception, as these bolts are color-coded on the threaded end projecting from the concrete. Permanent stamping with manufacturer’s identifier and/or grade symbol is a supplemental requirement of the specification and is only necessary when requested in the purchase order. Permanent marking of the bolt head is not required.

Rods and Studs

Most grades of threaded rods 3/8” diameter and larger (all thread, thread each end, or thread one end) possess the same stamping requirements as headed bolts, with the grade symbol and manufacturer’s identifier required on one end only. ASTM F1554 anchor rods only require color coding on the end projecting from the concrete unless permanent identification is requested on the purchase order.

Bent Bolts

Marking requirements on bent anchor bolts, U-bolts, eye bolts, etc. are somewhat subjective. Portland Bolt chooses to permanently mark any high strength (quenched and tempered) bent fastener that we manufacture, so that it can be easily identified, since most high strength bolts are used in critical applications. These markings again include our manufacturer’s identification and the grade symbol. The exception is ASTM F1554 which is color-coded unless permanent marking is specified.

ASTM A320 Grades L7 and L43 also requires that the Charpy testing temperature be marked on the head of a bolt or end of a threaded rod if the testing is performed at a service temperature that is less than -150 degrees.

Marking Requirements on Nuts

Certain grades of ASTM A563 and A194 hex nuts and heavy hex nuts require grade identification and manufacturer’s identification as follows:

A563 nut specification marking requirements:

Grade Required marking
O, A, B No marking required
C Manufacturers ID plus 3 circumferential lines 120 apart
C3 Manufacturers ID plus 3 circumferential lines 120 apart plus numeral 3
D Manufacturers ID plus D
DH Manufacturers ID plus DH
DH3 Manufacturers ID plus DH-3 if heavy hex, HX3 if standard hex

A194 nut specification requires manufacturers identification plus the following grade symbols:

Grade and Type Nuts Hot-Forged or Cold-Punched Nuts Machined from Bar Stock Nuts Manufactured in Accordance with 6.6
1 1 1B -
2 2 2B -
2HB 2H 2HB -
3 3 3B -
4 4 4B -
4LC 4L 4BL -
6 6 6B -
6F 6F 6FB -
7 7 7B -
7LC 7L 7BL -
7MB 7M 7MB -
8 8 8B 8A
8C 8C 8CB 8CA
8M 8M 8MB 8MA
8T 8T 8TB 8TA
8F 8F 8FB 8FA
8P 8P 8PB 8PA
8N 8N 8NB 8NA
8R 8R 8RB 8RA
8S 8S 8SB 8SA
9C 9C 9CB 9CA
16 16 16B -

Written ,


    @Felix- A194 Grade 8R is the designation for nuts made from UNS 20910 stainless, commonly known as Nitronic 50. We are not aware that the R stands for anything specific.

    Dear Sir ,
    Good evening
    We would like to know the prices for the complete machine for producing the rods , headed bolts and other types . The size is from 14mm-20mm.


    @Mzaki- We don’t have a price list, we quote all our jobs on a per order basis. If you would like to send your specific requirements, we’d be happy to take a look at it. We would be able to quote an imperial conversion, as we cannot manufacture metric sizes.

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