ISO 7411 HV Structural Bolts
ISO 7411 heavy hex head bolts for high-strength structural (HV) bolted connections, M12 to M36 — the full attribute grid (ds, dw, e, k, s, b thread-length bands) plus the 38-length ls/lg ladder from l 30 to l 200.
Last updated: 2026-11
Specifications
ISO 7411 is the bolt (not the screw) of the HV structural pair: a heavy hex head with a defined washer-face geometry, sized for preloaded friction-grip connections in steel construction. The collected grid runs M12 → M36 with the thread-length b bands split above/under the source's continuous stepped line (M12: 21/23 up to M36: 48/50), head height k nominal 8 → 23, width across flats s 22 → 60, and the bearing-face diameters dw 20 → 57. The length ladder is the working document for a structural order: 38 nominal lengths l 30 → 200, each with its tolerance band (±1,05 at the short end widening to the −4,6/+4,6-style bands past l 180 as printed), and per-size ls (Min.) / lg (Max.) columns so thread engagement and grip can be checked against the joint stack before ordering. Where it sits in the catalog: this page carries the ISO 7411 designation itself; the EN 14399-4 / DIN 6914 HV bolt pages already in the catalog cover their own designations — order by the standard your drawing names. Property class, coating and lengths beyond l 200 are not on the collected page — per RFQ; lead time, MOQ and pricing: contact for confirmation.
| Standard | ISO 7411 — hex head bolts for high-strength (HV) structural bolting |
|---|---|
| Size range | M12 – M36 in the collected rows |
| Head | k nominal 8 → 23; s 22 → 60; e (min.) 23,91 → 66,44 |
| Thread-length bands (b) | above/under the stepped line: M12 21/23 → M36 48/50 |
| Length ladder | l 30 – 200 (38 nominal lengths) with per-size ls Min. / lg Max. |
| Not tabulated | Property class, material, coating, lengths beyond l 200 — per RFQ; lead time, MOQ and pricing: contact for confirmation |
| Designation note | EN 14399-4 / DIN 6914 HV bolts are separate designations already in this catalog — order by drawing designation |
| Attribute | Qualifier | M12 | M16 | M20 | M22 | M24 | M27 | M30 | M36 |
|---|---|---|---|---|---|---|---|---|---|
| Thread d | M12 | M16 | M20 | M22 | M24 | M27 | M30 | M36 | |
| P | 1,75 | 2 | 2,5 | 2,5 | 3 | 3 | 3,5 | 4 | |
| b (see tab. below) | above tde continuous steped line | 21 | 26 | 31 | 32 | 34 | 37 | 40 | 48 |
| b (see tab. below) | under tde continuous steped line | 23 | 28 | 33 | 34 | 37 | 39 | 42 | 50 |
| c | Min. | 0,4 | 0,4 | 0,4 | 0,4 | 0,4 | 0,4 | 0,4 | 0,4 |
| c | Max. | 0,6 | 0,6 | 0,8 | 0,8 | 0,8 | 0,8 | 0,8 | 0,8 |
| da | Max. | 15,2 | 19,2 | 24 | 26 | 28 | 32 | 35 | 41 |
| ds | Nomial size | 12 | 16 | 20 | 22 | 24 | 27 | 30 | 36 |
| ds | Min. | 11,3 | 15,3 | 19,16 | 21,16 | 23,16 | 26,16 | 29,16 | 35 |
| ds | Max. | 12,7 | 16,7 | 20,84 | 22,84 | 24,84 | 27,84 | 30,84 | 37 |
| dw | Min. | 20 | 25 | 30 | 34 | 39 | 43,5 | 47,5 | 57 |
| e | Min. | 23,91 | 29,56 | 35,03 | 39,55 | 45,2 | 50,85 | 55,37 | 66,44 |
| k | Nomial size | 8 | 10 | 13 | 14 | 15 | 17 | 19 | 23 |
| k | Min. | 7,55 | 9,25 | 12,1 | 13,1 | 14,1 | 16,1 | 17,95 | 21,95 |
| k | Max. | 8,45 | 10,75 | 13,9 | 14,9 | 15,9 | 17,9 | 20,05 | 24,05 |
| k´ | Min. | 5,28 | 6,47 | 8,47 | 9,17 | 9,87 | 11,27 | 12,56 | 15,36 |
| r | Min. | 1,2 | 1,2 | 1,5 | 1,5 | 1,5 | 2 | 2 | 2 |
| s | Nomial size = max. | 22 | 27 | 32 | 36 | 41 | 46 | 50 | 60 |
| s | Min. | 21,16 | 26,16 | 31 | 35 | 40 | 45 | 49 | 58,8 |
- Row 3 (b (see tab. below)): the source prints the b band labels as "above tde continuous steped line" / "under tde continuous steped line" — carried verbatim, not corrected.
- Row 8 (ds): ds Min. at M36 prints 35 (the smaller sizes run a ,16 suffix: 11,3 → 29,16). Carried verbatim; confirm M36 shank minimum per RFQ.
- Row 18 (s): s Min. at M36 prints 58,8 (smaller sizes run a ,16 suffix). Carried verbatim.
| l Nominal | l Min. | l Max. | M12 ls Min. | M12 lg Max. | M16 ls Min. | M16 lg Max. | M20 ls Min. | M20 lg Max. | M22 ls Min. | M22 lg Max. | M24 ls Min. | M24 lg Max. | M27 ls Min. | M27 lg Max. | M30 ls Min. | M30 lg Max. | M36 ls Min. | M36 lg Max. |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 30 | 28,95 | 31,05 | 3,75 | 9 | ||||||||||||||
| 35 | 33,75 | 36,25 | 8,75 | 14 | ||||||||||||||
| 40 | 38,75 | 41,25 | 13,75 | 19 | 8 | 14 | ||||||||||||
| 45 | 43,75 | 46,25 | 16,75 | 22 | 13 | 19 | 6,5 | 14 | ||||||||||
| 50 | 48,75 | 51,25 | 21,75 | 27 | 18 | 24 | 11,5 | 19 | 10,5 | 18 | ||||||||
| 55 | 53,5 | 56,5 | 26,75 | 32 | 23 | 29 | 16,5 | 24 | 15,5 | 23 | ||||||||
| 60 | 58,5 | 61,5 | 31,75 | 37 | 28 | 34 | 21,5 | 29 | 20,5 | 28 | 17 | 26 | ||||||
| 65 | 63,5 | 66,5 | 36,75 | 42 | 33 | 39 | 26,5 | 34 | 25,5 | 33 | 22 | 31 | ||||||
| 70 | 68,5 | 71,5 | 41,75 | 47 | 38 | 44 | 31,5 | 39 | 30,5 | 38 | 27 | 36 | 24 | 33 | ||||
| 75 | 73,5 | 76,5 | 46,75 | 52 | 41 | 47 | 36,5 | 44 | 35,5 | 43 | 32 | 41 | 29 | 38 | 24,5 | 35 | ||
| 80 | 78,5 | 81,5 | 51,75 | 57 | 46 | 52 | 41,5 | 49 | 40,5 | 48 | 37 | 46 | 34 | 43 | 29,5 | 40 | ||
| 85 | 83,25 | 86,75 | 56,75 | 62 | 51 | 57 | 46,5 | 54 | 45,5 | 53 | 42 | 51 | 39 | 48 | 34,5 | 45 | 25 | 37 |
| 90 | 88,25 | 91,75 | 61,75 | 67 | 56 | 62 | 49,5 | 57 | 48,5 | 56 | 44 | 53 | 44 | 53 | 39,5 | 50 | 30 | 42 |
| 95 | 93,25 | 96,75 | 66,75 | 72 | 61 | 67 | 54,5 | 62 | 53,5 | 61 | 49 | 58 | 49 | 58 | 44,5 | 55 | 35 | 47 |
| 100 | 98,25 | 101,75 | 66 | 72 | 59,4 | 67 | 58,5 | 66 | 54 | 63 | 52 | 61 | 47,5 | 58 | 40 | 52 | ||
| 105 | 103,25 | 106,75 | 71 | 77 | 64,5 | 72 | 63,5 | 71 | 59 | 68 | 57 | 66 | 52,5 | 63 | 43 | 55 | ||
| 110 | 108,25 | 111,75 | 76 | 82 | 69,5 | 77 | 68,5 | 76 | 64 | 73 | 62 | 71 | 57,5 | 68 | 48 | 60 | ||
| 115 | 113,25 | 116,75 | 81 | 87 | 74,5 | 82 | 73,5 | 81 | 69 | 78 | 67 | 76 | 62,5 | 73 | 53 | 65 | ||
| 120 | 118,25 | 121,75 | 86 | 92 | 79,5 | 87 | 78,5 | 86 | 74 | 83 | 72 | 81 | 67,5 | 78 | 58 | 70 | ||
| 125 | 123 | 127 | 91 | 97 | 84,5 | 92 | 83,5 | 91 | 79 | 88 | 77 | 86 | 72,5 | 83 | 63 | 75 | ||
| 130 | 128 | 132 | 96 | 102 | 89,5 | 97 | 88,5 | 96 | 84 | 93 | 82 | 91 | 77,5 | 88 | 68 | 80 | ||
| 135 | 133 | 137 | 94,5 | 102 | 93,5 | 101 | 89 | 98 | 87 | 96 | 82,5 | 93 | 73 | 85 | ||||
| 140 | 138 | 142 | 99,5 | 107 | 98,5 | 106 | 94 | 103 | 92 | 101 | 87,5 | 98 | 78 | 90 | ||||
| 145 | 143 | 147 | 104,5 | 112 | 103,5 | 111 | 99 | 108 | 97 | 106 | 92,5 | 103 | 83 | 95 | ||||
| 150 | 148 | 152 | 109,5 | 117 | 108,5 | 116 | 104 | 113 | 102 | 111 | 97,5 | 108 | 88 | 100 | ||||
| 155 | 151 | 159 | 114,5 | 122 | 113,5 | 121 | 109 | 118 | 107 | 116 | 102,5 | 113 | 93 | 105 | ||||
| 160 | 156 | 164 | 118,5 | 126 | 114 | 123 | 112 | 121 | 107,5 | 118 | 98 | 110 | ||||||
| 165 | 161 | 169 | 123,5 | 131 | 119 | 128 | 117 | 126 | 112,5 | 123 | 103 | 115 | ||||||
| 170 | 166 | 174 | 124 | 133 | 122 | 131 | 117,5 | 128 | 108 | 120 | ||||||||
| 175 | 171 | 179 | 129 | 138 | 127 | 136 | 122,5 | 133 | 113 | 125 | ||||||||
| 180 | 176 | 184 | 134 | 143 | 132 | 141 | 127,5 | 138 | 118 | 130 | ||||||||
| 185 | 180,4 | 189,6 | 139 | 148 | 137 | 146 | 132,5 | 143 | 123 | 135 | ||||||||
| 190 | 185,4 | 194,6 | 144 | 153 | 142 | 151 | 137,5 | 148 | 128 | 140 | ||||||||
| 195 | 190,4 | 199,6 | 149 | 158 | 147 | 156 | 142,5 | 153 | 133 | 145 | ||||||||
| 200 | 195,4 | 204,6 | 152 | 161 | 147,5 | 158 | 138 | 150 |
- Row 16 (105): M20 ls at l 100 prints 59,4 (the ladder otherwise steps in ,5 increments: 54,5 / 64,5 / ...). Carried verbatim.
- Row 33 (190): from l 185 the length band changes form (Min. 180,4 / Max. 189,6 at l 185, versus the ,75-offset bands before) — the source's banding as printed; carried verbatim.
Materials
- Material, property class and coating specified per RFQ — HV structural bolting is ordered as an assembly (bolt + nut + washer) with matched class and lubrication for the preload method (k-class or combined method); state the connection design standard and the tensioning method at quotation
Ordering & documentation
Documents
Shipments are backed by Mill Test Certificate (MTC), Dimensional Report, Salt Spray Test Report on request, with full batch traceability from raw material to finished product. Quality management follows the owner-confirmed compliance list: ISO 9001:2015, RoHS, REACH. Exact document sets are confirmed on the order.
Quotation
- The fastener family (ISO 7411 HV Structural Bolts) plus the standard designation from your drawing — DIN / ISO / JIS / ASTM / ANSI, or a drawing for custom parts.
- Size (diameter and length), thread type (metric or inch), property class or grade, and coating or finish.
- Quantity per size and your target delivery date.
- Destination country, and any required documents (for example a mill test certificate) so the quote includes them.
Sample & supply
Minimum order quantity is 1,000–10,000 pieces depending on size. Stock items run 3–7 days. High-strength and custom parts run 15–25 days. Quantities or variants outside the standard range are confirmed at quotation.
Storage & shipping
Parts are packed for export and shipped factory-direct to buyers in Europe, Asia, the Americas and the Middle East. Store fasteners dry and protected until installation, and keep coated parts in their packaging until use; specific packing and preservation requirements can be stated on the order and confirmed at quotation.
Frequently asked questions
ISO 7411 vs the EN 14399-4 / DIN 6914 HV bolts already in the catalog — are they interchangeable?
They describe the same family of heavy hex head structural bolts, but they are separate designations and the catalog keeps each on its own page because the controlled dimensions differ in what they fix. The ISO 7411 grid collected here tabulates ds, dw, e, k, k´, r, s and the b thread-length bands for M12–M36, plus the 38-length ls/lg ladder; the EN 14399-4 page is organized around the EN 14399 system's assembly requirements (k-class, DTI use, nut/washer pairing). A drawing that names ISO 7411 should be quoted from this page; a drawing specified to EN 14399-4 should stay on that designation. If your drawing gives only "HV bolt M24", match the size and grip from the ladder here and confirm the designation per RFQ before the order is cut. Practical note for both: the ls/lg columns are the columns that decide whether the bolt fits your stack — ls Min. must reach through the grip with full thread in the nut, lg Max. must not bottom out — so check them against the actual plate pack, not just the diameter.
Why does the ls/lg ladder change band shape at l 185, and why does M20 at l 100 print 59,4?
Both are carried exactly as the source prints them, and both are flagged in the table. The length tolerance bands run at a −1,05/+1,05-style offset through l 180, then switch form at l 185 (Min. 180,4 / Max. 189,6) through l 200 — the source's banding, not a normalization. The M20 column at l 100 prints 59,4 where every neighbouring ls value steps in ,5 increments (54,5 at l 95, 64,5 at l 105); a decimal-comma slip is possible in a source of this kind, so the flag tells you to confirm that one cell per RFQ if your order lands on M20 × 100. Everything else in the ladder — including the full M12, M16, M22, M24, M27, M30 and M36 columns — steps cleanly and can be quoted as printed.
Related knowledge
- What Bolt Property Classes 8.8, 10.9 and 12.9 Encode — and When High Strength Stops Being the Right Choice
- Bolt Grade Selection: ISO 898-1 8.8/10.9/12.9 vs ASTM A307 and A325
- 8.8 vs 10.9 vs 12.9 Bolts: Strength, Hardness and Cost — What the Evidence Settles
- Calculating Bolt Preload and Clamp Force: Torque, Friction and Tightening Method
- How to Determine Tightening Torque and Choose a Tightening Method for a Bolted Joint
- Fastener Failure Modes: Which Fatigue, Creep and SCC Controls the Evidence Supports
- Hydrogen Embrittlement in High-Strength Bolts: Which Grades Need Controls, Which Coatings and Baking Schedules Are Acceptable, and What to Require Before the RFQ
Request a Quote
Get factory-direct pricing from the manufacturer.
What to include in your inquiry
- ✓ Standard and property class (e.g. DIN 912, ISO 4762, class 8.8) — or a drawing for custom parts.
- ✓ Sizes, lengths and thread type (metric or inch).
- ✓ Quantity per size and your target delivery date.
- ✓ Destination country, plus any coating or finish requirement.
- ✓ Any documents you need with the shipment (e.g. mill test certificate) so the quote includes them.
- ✓ Your inquiry goes straight to the factory team by email and gets a reply within 24 hours.
- ✓ Factory-direct pricing
- ✓ Standard and custom specifications
- ✓ Factory-direct export to buyers in Europe, Asia, the Americas and the Middle East
- ✓ Full fastener family support