# Welded link chain: proof coil Grade 30, high test 43, transport 70, alloy 80 and 100 — material diameter, inside length, inside width (NACM)

> What are the link dimensions of 1/4, 5/16 and 3/8 chain: material diameter, inside length and inside width for Grade 30, 43, 70, 80 and 100?

- Category: Hardware › Rigging
- Kind: Standard part
- Basis: NACM-based tables from 1st Chain Supply, Perfection Chain, Jinbo Marine, a distributor catalogue and McMaster-Carr; numbers only, load ratings left out on purpose
- Page: https://xemstudio.com/objects/welded-link-chain-nacm-grades-30-43-70-80-100/ · JSON: https://xemstudio.com/api/geometry?object=welded-link-chain-nacm-grades-30-43-70-80-100 · Plain text: https://xemstudio.com/objects/welded-link-chain-nacm-grades-30-43-70-80-100/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

**Exact dimensions.** True size, with no tolerance added.

## Notes

- Each row is one chain size as one source prints it: material diameter (wire diameter of the link), inside length and inside width of one link. Inch rows are inches, millimetre rows are millimetres; the last column converts the three figures (computed here, × 25.4 or ÷ 25.4) so inch and metric sources can be compared. Trade size is the name the maker uses, not a measured dimension: the real wire is larger or smaller than the name (a 1/4 reg link is 0.275 in wire).
- Where the sources print a link style it is kept in the trade-size cell: regular link, long link and ISO short link are different link proportions on the same wire (1/4 Grade 30: 1.020 in regular, 1.240 in long, 1.000 in ISO short inside length, 1st Chain Supply). Compare only like with like.
- The sources are different makers' catalogues and disagree: 1/4 Grade 30 inside length is 1.02 / 1.24 (1st Chain Supply by link style) against 1.24 (Perfection) and wire 0.275 against 0.276; 5/16 inside width is 0.49 (1st Chain Supply) against 0.44 (Perfection); Grade 80 3/8 wire is 0.40 in (McMaster) against 10 mm = 0.394 in (distributor catalogue) and inside length 1.22 in against 30 mm = 1.18 in. Jinbo Marine's NACM 1996/2003 tables give inside length as a maximum and inside width as a minimum; the NACM-style tables of the other sources do not say. The Jinbo transport (Grade 70) table lists '11.9' as the nominal size of its 10.3 mm wire row, and its Grade 43 table '13' for a 13.5 mm wire row; both are copied as printed.
- Grade 80 and Grade 100 are alloy chain for overhead lifting (the headings of the distributor catalogue name EN 818-2 with ASTM A391 for Grade 80 and ASTM A973 for Grade 100); proof coil, high test and transport chain are not for overhead lifting. Working load limits, proof loads and weights per length are printed by every source but are left out here on purpose: use the maker's sheet for the chain you buy, because ratings depend on grade, finish and marking. Grade 70 in the distributor catalogue has no wire diameter column, so none is shown.
- No file: a chain link is an oval of wire with a weld whose end radii and weld upset are not published in these tables, so a drawn link would be invented. McMaster-Carr sells chain with per-part STEP; its lifting-chain and transport-chain categories are linked, not copied. Short-link metric chain: short-link-chain-din-766-din-5685; roller chain is a different product: roller-chain-ansi-b29-1-25-to-80.

## Sizes

| grade | source | trade size / nominal | material (wire) dia | inside length | inside width | unit | dia / length / width converted (mm or in, computed) |
|---|---|---|---|---|---|---|---|
| Grade 30 proof coil | 1st Chain Supply | 1/8 reg link | 0.160 | 0.900 | 0.270 | in | 4.06 / 22.9 / 6.9 |
| Grade 30 proof coil | 1st Chain Supply | 3/16 reg link | 0.210 | 0.950 | 0.400 | in | 5.33 / 24.1 / 10.2 |
| Grade 30 proof coil | 1st Chain Supply | 1/4 long link | 0.275 | 1.240 | 0.460 | in | 6.99 / 31.5 / 11.7 |
| Grade 30 proof coil | 1st Chain Supply | 1/4 reg link | 0.275 | 1.020 | 0.500 | in | 6.99 / 25.9 / 12.7 |
| Grade 30 proof coil | 1st Chain Supply | 1/4 ISO short link | 0.279 | 1.000 | 0.510 | in | 7.09 / 25.4 / 13.0 |
| Grade 30 proof coil | 1st Chain Supply | 5/16 long link | 0.330 | 1.300 | 0.490 | in | 8.38 / 33.0 / 12.4 |
| Grade 30 proof coil | 1st Chain Supply | 5/16 reg link | 0.330 | 1.150 | 0.490 | in | 8.38 / 29.2 / 12.4 |
| Grade 30 proof coil | 1st Chain Supply | 5/16 ISO short link | 0.342 | 1.100 | 0.510 | in | 8.69 / 27.9 / 13.0 |
| Grade 30 proof coil | 1st Chain Supply | 3/8 long link | 0.397 | 1.450 | 0.600 | in | 10.08 / 36.8 / 15.2 |
| Grade 30 proof coil | 1st Chain Supply | 3/8 reg link | 0.397 | 1.300 | 0.600 | in | 10.08 / 33.0 / 15.2 |
| Grade 30 proof coil | 1st Chain Supply | 3/8 ISO short link | 0.404 | 1.230 | 0.620 | in | 10.26 / 31.2 / 15.7 |
| Grade 30 proof coil | 1st Chain Supply | 1/2 reg link | 0.520 | 1.560 | 0.810 | in | 13.21 / 39.6 / 20.6 |
| Grade 30 proof coil | 1st Chain Supply | 1/2 ISO short link | 0.512 | 1.500 | 0.820 | in | 13.00 / 38.1 / 20.8 |
| Grade 30 proof coil | 1st Chain Supply | 5/8 reg link | 0.630 | 1.870 | 1.000 | in | 16.00 / 47.5 / 25.4 |
| Grade 30 proof coil | 1st Chain Supply | 3/4 reg link | 0.787 | 2.130 | 1.130 | in | 19.99 / 54.1 / 28.7 |
| Grade 30 proof coil | Perfection Chain | 1/8 | 0.156 | 0.94 | 0.25 | in | 3.96 / 23.9 / 6.3 |
| Grade 30 proof coil | Perfection Chain | 3/16 | 0.217 | 0.98 | 0.39 | in | 5.51 / 24.9 / 9.9 |
| Grade 30 proof coil | Perfection Chain | 1/4 | 0.276 | 1.24 | 0.50 | in | 7.01 / 31.5 / 12.7 |
| Grade 30 proof coil | Perfection Chain | 5/16 | 0.331 | 1.29 | 0.44 | in | 8.41 / 32.8 / 11.2 |
| Grade 30 proof coil | Perfection Chain | 3/8 | 0.394 | 1.38 | 0.55 | in | 10.01 / 35.1 / 14.0 |
| Grade 43 high test | 1st Chain Supply | 1/4 reg link | 0.274 | 1.020 | 0.500 | in | 6.96 / 25.9 / 12.7 |
| Grade 43 high test | 1st Chain Supply | 1/4 ISO short link | 0.274 | 0.845 | 0.410 | in | 6.96 / 21.5 / 10.4 |
| Grade 43 high test | 1st Chain Supply | 5/16 reg link | 0.330 | 1.150 | 0.490 | in | 8.38 / 29.2 / 12.4 |
| Grade 43 high test | 1st Chain Supply | 5/16 ISO short link | 0.330 | 1.030 | 0.510 | in | 8.38 / 26.2 / 13.0 |
| Grade 43 high test | 1st Chain Supply | 3/8 reg link | 0.397 | 1.300 | 0.600 | in | 10.08 / 33.0 / 15.2 |
| Grade 43 high test | 1st Chain Supply | 3/8 ISO short link | 0.394 | 1.220 | 0.590 | in | 10.01 / 31.0 / 15.0 |
| Grade 43 high test | 1st Chain Supply | 1/2 reg link | 0.520 | 1.560 | 0.810 | in | 13.21 / 39.6 / 20.6 |
| Grade 43 high test | 1st Chain Supply | 1/2 ISO short link | 0.510 | 1.590 | 0.760 | in | 12.95 / 40.4 / 19.3 |
| Grade 43 high test | 1st Chain Supply | 5/8 reg link | 0.630 | 1.870 | 1.000 | in | 16.00 / 47.5 / 25.4 |
| Grade 43 high test | 1st Chain Supply | 5/8 ISO short link | 0.630 | 1.790 | 0.900 | in | 16.00 / 45.5 / 22.9 |
| Grade 43 high test | 1st Chain Supply | 3/4 reg link | 0.781 | 2.610 | 1.020 | in | 19.84 / 66.3 / 25.9 |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 4 mm | 4 | 23.9 max | 6.4 min | mm | — |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 5.5 mm | 5.5 | 24.8 max | 7.7 min | mm | — |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 7 mm | 7 | 31.5 max | 9.8 min | mm | — |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 8 mm | 8.4 | 32.8 max | 11.2 min | mm | — |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 10 mm | 10 | 35 max | 14 min | mm | — |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 11.9 mm | 11.9 | 41.5 max | 16.6 min | mm | — |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 13 mm | 13 | 45.6 max | 18.2 min | mm | — |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 16 mm | 16 | 56 max | 20 min | mm | — |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 20 mm | 20 | 70 max | 25 min | mm | — |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 22 mm | 22 | 77 max | 27.5 min | mm | — |
| Grade 30 (proof coil) NACM 1996/2003 | Jinbo Marine | 25 mm | 26 | 90.9 max | 31.7 min | mm | — |
| Grade 43 (high test) NACM 1996/2003 | Jinbo Marine | 7 mm | 7 | 31.5 max | 9.8 min | mm | — |
| Grade 43 (high test) NACM 1996/2003 | Jinbo Marine | 8.7 mm | 8.7 | 32.8 max | 11.2 min | mm | — |
| Grade 43 (high test) NACM 1996/2003 | Jinbo Marine | 10 mm | 10.3 | 35 max | 14 min | mm | — |
| Grade 43 (high test) NACM 1996/2003 | Jinbo Marine | 11.9 mm | 11.9 | 41.6 max | 16.6 min | mm | — |
| Grade 43 (high test) NACM 1996/2003 | Jinbo Marine | 13 mm | 13.5 | 45.5 max | 18.2 min | mm | — |
| Grade 43 (high test) NACM 1996/2003 | Jinbo Marine | 16 mm | 16 | 56 max | 20 min | mm | — |
| Grade 43 (high test) NACM 1996/2003 | Jinbo Marine | 20 mm | 20 | 70 max | 25 min | mm | — |
| Grade 43 (high test) NACM 1996/2003 | Jinbo Marine | 22 mm | 22 | 77 max | 27.5 min | mm | — |
| Grade 70 (transport) NACM 1996/2003 | Jinbo Marine | 7 mm | 7 | 31.8 max | 9.8 min | mm | — |
| Grade 70 (transport) NACM 1996/2003 | Jinbo Marine | 8.7 mm | 8.7 | 32.8 max | 11.2 min | mm | — |
| Grade 70 (transport) NACM 1996/2003 | Jinbo Marine | 11.9 mm | 10.3 | 35 max | 14 min | mm | — |
| Grade 70 (transport) NACM 1996/2003 | Jinbo Marine | 13 mm | 13.5 | 45.5 max | 18.2 min | mm | — |
| Grade 70 (transport) NACM 1996/2003 | Jinbo Marine | 16 mm | 16 | 56 max | 20 min | mm | — |
| Grade 70 (transport) NACM 1996/2003 | Jinbo Marine | 20 mm | 20 | 70 max | 25 min | mm | — |
| Grade 70 transport | Distributor catalogue section 2 | 1/4 | not printed | 31.5 | 9.7 | mm | — |
| Grade 70 transport | Distributor catalogue section 2 | 5/16 | not printed | 32.8 | 11.2 | mm | — |
| Grade 70 transport | Distributor catalogue section 2 | 3/8 | not printed | 35.0 | 14.0 | mm | — |
| Grade 70 transport | Distributor catalogue section 2 | 1/2 | not printed | 45.5 | 18.3 | mm | — |
| Grade 80 alloy (EN 818-2 / ASTM A391 as headed) | Distributor catalogue section 2 | 9/32 | 7 | 21 | 9 – 10.5 | mm | 0.276 / 0.827 in |
| Grade 80 alloy (EN 818-2 / ASTM A391 as headed) | Distributor catalogue section 2 | 5/16 | 8 | 24 | 10 – 12 | mm | 0.315 / 0.945 in |
| Grade 80 alloy (EN 818-2 / ASTM A391 as headed) | Distributor catalogue section 2 | 3/8 | 10 | 30 | 12.5 – 15 | mm | 0.394 / 1.181 in |
| Grade 80 alloy (EN 818-2 / ASTM A391 as headed) | Distributor catalogue section 2 | 1/2 | 13 | 39 | 16.3 – 20 | mm | 0.512 / 1.535 in |
| Grade 80 alloy (EN 818-2 / ASTM A391 as headed) | Distributor catalogue section 2 | 5/8 | 16 | 48 | 20 – 24 | mm | 0.630 / 1.890 in |
| Grade 80 alloy (EN 818-2 / ASTM A391 as headed) | Distributor catalogue section 2 | 3/4 | 20 | 60 | 25 – 30 | mm | 0.787 / 2.362 in |
| Grade 80 alloy (EN 818-2 / ASTM A391 as headed) | Distributor catalogue section 2 | 7/8 | 22 | 66 | 28 – 33 | mm | 0.866 / 2.598 in |
| Grade 80 alloy (EN 818-2 / ASTM A391 as headed) | Distributor catalogue section 2 | 1 | 26 | 78 | 35 – 39 | mm | 1.024 / 3.071 in |
| Grade 80 alloy (EN 818-2 / ASTM A391 as headed) | Distributor catalogue section 2 | 1-1/4 | 32 | 96 | 40 – 42 | mm | 1.260 / 3.780 in |
| Grade 80 alloy, black painted | McMaster-Carr (as printed) | 7/32 | 0.22 | 0.68 | 0.32 | in | 5.59 / 17.3 / 8.1 |
| Grade 80 alloy, black painted | McMaster-Carr (as printed) | 9/32 | 0.28 | 0.88 | 0.41 | in | 7.11 / 22.4 / 10.4 |
| Grade 80 alloy, black painted | McMaster-Carr (as printed) | 5/16 | 0.33 | 1.02 | 0.48 | in | 8.38 / 25.9 / 12.2 |
| Grade 80 alloy, black painted | McMaster-Carr (as printed) | 3/8 | 0.40 | 1.22 | 0.57 | in | 10.16 / 31.0 / 14.5 |
| Grade 80 alloy, black painted | McMaster-Carr (as printed) | 1/2 | 0.51 | 1.54 | 0.69 | in | 12.95 / 39.1 / 17.5 |
| Grade 80 alloy, black painted | McMaster-Carr (as printed) | 5/8 | 0.63 | 1.93 | 0.92 | in | 16.00 / 49.0 / 23.4 |
| Grade 80 alloy, black painted | McMaster-Carr (as printed) | 3/4 | 0.79 | 2.44 | 1.01 | in | 20.07 / 62.0 / 25.7 |
| Grade 100 alloy (EN 818-2 / ASTM A973 as headed) | Distributor catalogue section 2 | 9/32 | 7.4 | 22.1 | 10.4 | mm | 0.291 / 0.870 in |
| Grade 100 alloy (EN 818-2 / ASTM A973 as headed) | Distributor catalogue section 2 | 5/16 | 8.4 | 25.7 | 12.7 | mm | 0.331 / 1.012 in |
| Grade 100 alloy (EN 818-2 / ASTM A973 as headed) | Distributor catalogue section 2 | 3/8 | 10.2 | 31 | 14.5 | mm | 0.402 / 1.220 in |
| Grade 100 alloy (EN 818-2 / ASTM A973 as headed) | Distributor catalogue section 2 | 1/2 | 13.2 | 40.1 | 19.1 | mm | 0.520 / 1.579 in |
| Grade 100 alloy (EN 818-2 / ASTM A973 as headed) | Distributor catalogue section 2 | 5/8 | 16.3 | 49 | 22.1 | mm | 0.642 / 1.929 in |
| Grade 100 alloy (EN 818-2 / ASTM A973 as headed) | Distributor catalogue section 2 | 3/4 | 20.3 | 61.5 | 27.7 | mm | 0.799 / 2.421 in |
| Grade 100 alloy (EN 818-2 / ASTM A973 as headed) | Distributor catalogue section 2 | 7/8 | 22.4 | 68.6 | 32.5 | mm | 0.882 / 2.701 in |
| Grade 100 alloy (EN 818-2 / ASTM A973 as headed) | Distributor catalogue section 2 | 1 | 26 | 78 | 37 | mm | 1.024 / 3.071 in |
| Grade 100 alloy, steel | McMaster-Carr (as printed) | 7/32 | 0.22 | 0.68 | 0.31 | in | 5.59 / 17.3 / 7.9 |
| Grade 100 alloy, steel | McMaster-Carr (as printed) | 9/32 | 0.28 | 0.83 | 0.37 | in | 7.11 / 21.1 / 9.4 |
| Grade 100 alloy, steel | McMaster-Carr (as printed) | 5/16 | 0.32 | 0.95 | 0.43 | in | 8.13 / 24.1 / 10.9 |
| Grade 100 alloy, steel | McMaster-Carr (as printed) | 3/8 | 0.39 | 1.18 | 0.53 | in | 9.91 / 30.0 / 13.5 |
| Grade 100 alloy, steel | McMaster-Carr (as printed) | 1/2 | 0.51 | 1.54 | 0.69 | in | 12.95 / 39.1 / 17.5 |
| Grade 100 alloy, steel | McMaster-Carr (as printed) | 5/8 | 0.63 | 1.89 | 0.85 | in | 16.00 / 48.0 / 21.6 |
| Grade 100 alloy, steel | McMaster-Carr (as printed) | 3/4 | 0.81 | 2.42 | 1.14 | in | 20.57 / 61.5 / 29.0 |

## Where the files are

- 1st Chain Supply: [Grade 30 Proof Coil chain specifications (NACM / ASTM A413 Grade 30): trade size, material diameter T, inside length L, inside width W](https://www.1st-chainsupply.com/content/Tech/30chainspecs.pdf) — web — Maker sheet; numbers only
- 1st Chain Supply: [Grade 43 High Test chain specifications: trade size, material diameter T, inside length L, inside width W](https://www.1st-chainsupply.com/content/Tech/43chainspecs.pdf) — web — Maker sheet; numbers only
- Perfection Chain Products: [Specs Proof Coil Grade 30: trade size, material size A, inside link length B, inside link width C](https://www.perfectionchain.com/wp-content/uploads/2019/05/Specs-Proof-Coil-Grade-30.pdf) — web — Maker sheet; numbers only
- Jinbo Marine: [American Standard Link Chain NACM1996/2003: proof coil (G30), high test (G43), transport (G70): nominal size, material diameter, inside length max, inside width min (mm)](https://www.jinbomarine.com/pdf/American-Standard-Link-Chain-NACM1996-2003) — web — Maker sheet; numbers only
- Chain distributor catalogue, section 2 (hosted on a Shopify CDN; maker not named in the text read): [Grade 70 transport, Grade 80 and Grade 100 overhead lifting chain: trade size, material diameter, inside length, inside width (mm)](https://cdn.shopify.com/s/files/1/0445/7185/2960/files/SECTION-2-min.pdf) — web — Distributor catalogue; numbers only
- McMaster-Carr: [Welded chain for lifting: Grade 80 and Grade 100 steel chain tables, trade size with Thk. / Wd. / Lg. as printed on the category page](https://www.mcmaster.com/welded-chain-for-lifting) — web — Distributor catalogue page; numbers only
- McMaster-Carr: [Lifting chain (Grade 80, Grade 100 and others, per-part STEP) (free STEP/IGES per part, for your own design use; no redistribution)](https://www.mcmaster.com/products/lifting-chain/) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution (verify at link)
- McMaster-Carr: [Transport chain (Grade 30, 43, 70) (free STEP/IGES per part, for your own design use; no redistribution)](https://www.mcmaster.com/transport-chain) — STEP, IGES, PDF — McMaster-Carr site terms: personal design use, no redistribution (verify at link)

## Questions

**What is the wire diameter of 1/4 proof coil (Grade 30) chain?**

0.275 in (1st Chain Supply, regular, long and ISO-short rows list 0.275 to 0.279 in), 0.276 in in Perfection Chain's sheet; Jinbo Marine's metric NACM table lists 7 mm for its 7 mm nominal row.

**What is the inside length of 3/8 Grade 70 chain?**

35.0 mm with an inside width of 14.0 mm in the distributor catalogue read here; Jinbo Marine's Grade 70 table gives 35 mm max and 14 mm min for the 10.3 mm wire row.

**What is the difference between a regular, long and ISO short link?**

They are different link proportions on the same wire; for 1/4 Grade 30 the sheet lists inside lengths of 1.020 in (regular), 1.240 in (long) and 1.000 in (ISO short).

**Can I use Grade 30 or Grade 43 chain for overhead lifting?**

No. The 1st Chain Supply sheet says Grade 30 proof coil is not for overhead lifting; Grades 80 and 100 are the alloy lifting grades. Load ratings are not on this page.

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