JIS B 1180 names two families of hex bolt, and one of them is a normative annex

The standard says why it is there, and it is not “legacy”

The introduction, translated as closely as the sentence allows:

Clause 1 then restates it as a requirement: hexagon head bolts not according to ISO 4014 to ISO 4018, ISO 8676 and ISO 8765 are as specified in Annex JA.

⚠️ So a drawing that cites only "JIS B 1180" has not said which of the two it wants, and the number cannot settle it. A drawing citing ISO 4014 does not have that ambiguity, because there is only one thing ISO 4014 can mean.

⚠️ What this page does not tell you

Annex JA runs from page 55 to page 68. The free preview I could read stops at the beginning of clause 2, so I have not read a line of it.

⚠️⚠️ The thing everyone says about this topic is that the two families differ across flats. I have not read that part, so this page gives no across-flats values, does not say which family is larger, and does not say at which nominal sizes they differ.

Three things can be said: the annex exists, it is normative, and the standard states its own reason for it. For the dimensions, go to the standard.

The main body is seven ISO standards integrated into one

⚠️ Six of the seven are 2011 editions. ISO 4015 is a first edition from 1979, still serving as a basis for a 2014 standard.

The note in clause 1 gives the overall assessment as MOD, and repeats that MOD indicates, per ISO/IEC Guide 21-1, that the standard is modified — the same structure as JIS B 1176. But the reason differs, and so does one more thing.

Two things that do not transfer between the two standards

⚠️ One marks absence, the other marks alteration. Do not carry the reading of one into the other. In both, the list of changes with explanations sits in a comparison-table annex — Annex JC in B 1176, Annex JB in B 1180.

The second difference is the list clause 1 sends you to for anything beyond dimensions and product specification, selected by agreement between the parties: B 1180 names JIS B 0205-4, B 0209-1, B 1003, B 1009, B 1021, B 1051 and B 1054-1, where B 1176 names B 0205-2, B 0209-2, B 1009, B 1021, B 1051, B 1054-1 and B 1057. Overlapping, not the same. A list memorised from one does not transfer.

The same shape as where standards stop: the scope covers hexagon head bolts in steel, stainless and non-ferrous metal, and material, property class and finish are somewhere else.

What to do with a Japanese drawing

• Ask which family before quoting. "JIS B 1180" alone does not answer it, and the difference is not a preference — the annex is normative
• If it is the main body, there is an ISO equivalent among the seven. If it is Annex JA, there is not — that is what the annex is for
• ⚠️ Bolts and screws are in the same standard. The title is “Hexagon head bolts and hexagon head screws”, and the seven bases split into bolts (ISO 4014, 4016, 8765) and screws (ISO 4017, 4018, 8676)
• Check the edition year on anything you find in English, for the reason in the note above
• Material, property class and finish still have to be stated separately

References, and how far the reading goes

• JIS B 1180:2014, Hexagon head bolts and hexagon head screws, read from the preview PDF published by the Japanese Standards Association (the preview path on webdesk.jsa.or.jp). ⚠️ No republishing site was used, and none should be — several of the English results for this standard are pirated copies.
• ⚠️⚠️ How far this page reads: cover, contents, introduction, clause 1 (scope and its note), and the opening of clause 2. Clause 3 (types), clause 4 (form, dimensions, product specification and designation examples), clause 5 (marking), the contents of Annex JA (pages 55–68), Annex JB and the commentary were not read. So this page cannot tell you how Annex JA and the main body differ dimensionally.
• ⚠️ The seven ISO standards were not read for this page. Their editions and titles are as listed by the JIS introduction and the note in clause 1.
• ⚠️ Nothing read in B 1176 has been carried into this page, or the reverse. The two differ in why they are MOD, in what the side lines mark, and in the list of standards clause 1 points to.

This is not one of the six steps. It shows up across them, or after assembly. Where the decisions that lead here were made is in specifying a screw, which sets out the order and why doing it out of order is rework.

Common questions

Does “JIS B 1180” on a drawing identify the bolt?

Not on its own. The standard contains Annex JA, titled “hexagon head bolts not according to ISO 4014 to ISO 4018, ISO 8676 and ISO 8765”, and it is marked normative rather than informative. Clause 1 states that such bolts are as specified in Annex JA. So which family is wanted has to be stated separately — an ambiguity a drawing citing ISO 4014 does not have.

Is Annex JA just legacy content?

The standard does not present it that way. The introduction says the characteristics of hexagon head bolts not according to the ISO standards are given in Annex JA in order to reflect the actual state of production and use in Japan. It is there to reflect what is made and used, and it is normative.

How do the main body and Annex JA differ dimensionally?

⚠️ This page cannot tell you. Annex JA runs pages 55 to 68 and the free preview stops at the beginning of clause 2. It is commonly said that the two differ across flats, but since that part was not read, no values, no direction and no nominal sizes are given here. Go to the standard for the dimensions.

Is JIS B 1180 the same as ISO 4014?

The note in clause 1 lists seven corresponding international standards — ISO 4014:2011, ISO 4015:1979, ISO 4016:2011, ISO 4017:2011, ISO 4018:2011, ISO 8676:2011 and ISO 8765:2011 — with an overall assessment of MOD, which per ISO/IEC Guide 21-1 means modified. Since seven were integrated into one, “the same as ISO 4014” accounts for one of them.

Can I rely on English excerpt tables for JIS B 1180?

Check the edition year first. Much of the English-language material refers to earlier editions — results citing 2004 and 1985 are easy to find — while the main-body-versus-annex structure described here comes from the 2014 revision. An excerpt table may not be describing the standard your customer is citing. Several of the English results are also pirated copies of the standard rather than licensed material.