Grade 12.9 hex bolts are engineered for the toughest jobs. Made from high-strength alloy steel and heat treated (quenched and tempered), they deliver class 12.9 performance. The “12.9” rating denotes very high mechanical values like tensile strength around 1200 MPa with a high yield ratio, setting the standard for high tensile 12.9 bolts.
The hex head allows easy wrench access and tight, secure clamping. You’ll see 12.9 hex head bolts specified in heavy machinery, automotive assemblies, plant equipment, and structural work where safety and uptime are critical.
Within metric property classes, class 12.9 bolts are among the strongest. Compared with grade 8.8, 12.9 bolt strength is significantly higher, with published minimum ultimate values reaching about 1242 MPa. Suppliers pair these with Grade 12.9 nuts when maximum tensile capacity is required. A key advantage of 12.9 fasteners is their thread form and heat-treat, which improve fatigue resistance, helping joints stay tight under continuous vibration.
Request QuoteManufacturer of 12.9 Bolt, Stud & Hex Nut | ASTM F568 Grade 12.9 Fasteners Suppliers
Unifit Fastener is a manufacturer and supplier of Grade 12.9 bolts, studs, and hex nuts to ASTM F568. Our 12.9 hex bolts are high-strength fasteners with minimum yield 1100 MPa and minimum tensile 1220 MPa. We produce Grade 12.9 hex head bolts, socket cap screws, 12.9 Allen bolts, studs, and threaded bar in alloy steel, quenched and tempered for hardness and durability. Sizes typically run M5–M160 with finishes including zinc plated, plain, and hot-dip galvanised, and we offer multiple head styles and thread forms to suit installation and torque needs.
As ASTM F568 Grade 12.9 fasteners suppliers, Unifit stocks parts for tight-access assemblies where 12.9 Allen bolts excel, while 12.9 metric hex head bolts remain the go-to for quick tool engagement and stable clamp load. Our 12.9 high tensile bolts serve oil and gas, petrochemical, chemical plants, heat exchangers, and shipbuilding, where vibration and high loads demand consistent performance. For continuous joints, Grade 12.9 threaded bar is available in one-end or both-end threaded forms and can connect components without separate nuts. Contact Unifit Fastener for pricing, dimensions, and immediate availability across 12.9 bolts, screws, studs, and threaded bars.
Send Your Enquiry
Specification of Grade 12.9 Bolts
Review Grade 12.9 bolt specs like grade, material, thread, and finish, so your selection matches load, torque, and service conditions.
| Grade 12.9 Bolts Grades | DIN 933 Grade 12.9 |
|---|---|
| Grade 12.9 Studs Standard | ASTM F568, ASME SF568 |
| Grade 12.9 Threaded Rod Size | Dia 1.6mm to 100 mm Inch 3/4" to 3.1/2" |
| Grade 12.9 Set Screws finish | Zinc plated / Plain / Hot dip galvanised |
Types of Class 12.9 Bolt
Explore class 12.9 options like hex bolts, socket cap screws, allen bolts, studs, and threaded rod to match access, preload, and tooling.
Grade 12.9 Bolt
Grade 12.9 Alloy Steel Fasteners
12.9 Grade Allen Bolt
Grade 12.9 Cap Screw
Grade 12.9 Socket Cap Screws
Grade 12.9 Fasteners
Grade 12.9 Flange Bolts
Grade 12.9 Galvanised Bolts
Class 12.9 Cap Screw
Grade 12.9 Hex Head Bolts
Grade 12.9 High Tensile Bolts
Grade 12.9 Head Bolts
Grade 12.9 Metric Studs
Grade 12.9 M10 Bolt
Class 12.9 Nut
Grade 12.9 Threaded Rod
Grade 12.9 Screw
Grade 12.9 Socket Head Cap Screws
Equivalent Grade of Class 12.9 Fasteners
Use this 12.9 fastener equivalents guide to cross-reference ISO/DIN with ASTM/SAE, ensuring interchangeability across standards.
| Material | Grade | ASTM | Tensile, min | Yield, min | ||
|---|---|---|---|---|---|---|
| Mpa | ksi | Mpa | ksi | |||
| Alloy steel; quench and tempered | Class 12.9 | A574 | 1220 | 177 | 1100 | 160 |
Grade 12.9 Stud Bolt Sizes
Check 12.9 stud diameter, pitch, and length in metric sizes. Correct sizing keeps thread engagement and clamp load within spec.
| Class and Material |
Nominal Size Range (mm) |
Mechanical Properties | ||
|---|---|---|---|---|
| Proof Load (MPa) |
Min. Yield Strength (MPa) |
Min. Tensile Strength (MPa) |
||
| Class 12.9 Alloy steel, quenched and tempered | 1.6mm - 100mm | 970 | 1100 | 1220 |
ASTM F568 Grade 12.9 Fasteners Dimension in MM
Confirm ASTM F568 grade 12.9 dimensions in mm for bolts, nuts, and screws. Metric data simplifies fit-up and inspection.
| Threaded Rod Thread | Threaded Rod Weight per metre | Threaded Rod Strength Threaded Rod Class 70 |
Threaded Rod Strength Threaded Rod Class 80 |
||
|---|---|---|---|---|---|
| Kg/m | 0.2% proof kN |
UTS kN |
0.2% proof kN |
UTS kN |
|
| M12 | 0.72 | 41.0 | 64.0 | 54.0 | 73.0 |
| M16 | 1.31 | 70.7 | 109.9 | 94.2 | 125.6 |
| M20 | 2.05 | 110.3 | 171.5 | 147.0 | 196.0 |
| M24 | 2.96 | 158.9 | 247.1 | 211.8 | 282.4 |
| M27 | 3.83 | 206.6 | 321.3 | 275.4 | 367.2 |
| M30 | 4.70 | 252.6 | 392.7 | 336.6 | 448.8 |
| M33 | 5.78 | 312.3 | 485.8 | 416.4 | 555.2 |
| M36 | 6.84 | 367.7 | 571.9 | 490.2 | 653.6 |
| M39 | 8.14 | 439.2 | 683.2 | 585.6 | 780.8 |
| M42 | 9.38 | 504.5 | 784.7 | 672.6 | 896.6 |
| M45 | 10.90 | 587.7 | 914.2 | 783.6 | 1044.8 |
| M48 | 12.32 | 662.9 | 1031.1 | 883.8 | 1178.4 |
| M52 | 14.65 | 791.1 | 1230.6 | 1054.8 | 1406.4 |
Grade 12.9 Alloy Steel Bolts Dimension Chart
Use this 12.9 alloy steel bolt chart to verify across-flats, head height, and thread details for accurate installation.
| Threaded Rod Thread | Threaded Rod Weight per metre | Threaded Rod Strength Threaded Rod Class 70 |
Threaded Rod Strength Threaded Rod Class 80 |
||
|---|---|---|---|---|---|
| Kg/m | 0.2% proof kN |
UTS kN |
0.2% proof kN |
UTS kN |
|
| M12 | 0.72 | 41.0 | 64.0 | 54.0 | 73.0 |
| M16 | 1.31 | 70.7 | 109.9 | 94.2 | 125.6 |
| M20 | 2.05 | 110.3 | 171.5 | 147.0 | 196.0 |
| M24 | 2.96 | 158.9 | 247.1 | 211.8 | 282.4 |
| M27 | 3.83 | 206.6 | 321.3 | 275.4 | 367.2 |
| M30 | 4.70 | 252.6 | 392.7 | 336.6 | 448.8 |
| M33 | 5.78 | 312.3 | 485.8 | 416.4 | 555.2 |
| M36 | 6.84 | 367.7 | 571.9 | 490.2 | 653.6 |
| M39 | 8.14 | 439.2 | 683.2 | 585.6 | 780.8 |
| M42 | 9.38 | 504.5 | 784.7 | 672.6 | 896.6 |
| M45 | 10.90 | 587.7 | 914.2 | 783.6 | 1044.8 |
| M48 | 12.32 | 662.9 | 1031.1 | 883.8 | 1178.4 |
| M52 | 14.65 | 791.1 | 1230.6 | 1054.8 | 1406.4 |
Stainless Steel Grade 12.9 Washer Sizes
Pair grade 12.9 washers with matching bolts and nuts. Correct OD/ID and thickness support preload and distribute load evenly.
| Size | Inside Diameter | Outside Diameter | Thickness |
|---|---|---|---|
| #2 | 3/32" | 1/4" | .020" |
| #4 | 1/8" | 5/16" | 1/32" |
| #6 | 5/32" | 3/8" | 3/64" |
| #8 | 3/16" | 7/16" | 3/64" |
| #10 | 7/32" | 1/2" | 3/64" |
| 1/4 | 9/32" | 5/8" | 1/16" |
| 5/16 | 11/32" | 11/16" | 1/16" |
| 3/8 | 13/32" | 13/16" | 1/16" |
| 7/16 | 15/32" | 59/64" | 1/16" |
| 1/2 | 17/32" | 1-1/16" | 3/32" |
| 9/16 | 19/32" | 1-3/16" | 3/32" |
| 5/8 | 21/32" | 1-5/16" | 3/32" |
| 3/4 | 13/16" | 1-1/2" | 9/64" |
| 7/8 | 15/16" | 1-3/4" | 9/64" |
| 1" | 1-1/16" | 2" | 9/64" |
| 1-1/8 | 1-3/16" | 2-1/4" | 9/64" |
| 1-1/4 | 1-5/16" | 2-1/2" | 5/32" |
| 1-1/2 | 1-7/16" | 3" | 3/16" |
| 1-5/8 | 1-3/4" | 3-3/4" | 3/16" |
| 1-3/4 | 1-7/8" | 4" | 3/16" |
| 2 | 2-1/8" | 4-1/2" | 3/16" |
Dimensions Schedule of Grade 12.9 Socket Cap Screws
Check 12.9 socket head cap screw head diameter/height and hex key size to ensure tool access and proper seating.
| DIA | M4 | M5 | M6 | M8 | M10 | M12 | M14 | M16 | M18 | M20 | M22 | M24 | M27 | M30 | M33 | M36 | M39 | M42 | M45 | M48 | M52 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pitch | 0.7 | 0.8 | 1 | 1.25 | 1.5 | 1.75 | 2 | 2 | 2.5 | 2.5 | 2.5 | 3 | 3 | 3.5 | 3.5 | 4 | 4 | 4.5 | 4.5 | 5 | 5 |
| Grade A upto length | 40 | 50 | 60 | 80 | 100 | 120 | 140 | 150 | Grade A not applicable to these dia’s | ||||||||||||
| Head Across Flat (S) Max Min(Grade A) Min (Grade B) | 7 | 8 | 10 | 13 | 16 | 18 | 21 | 24 | 27 | 30 | 34 | 36 | 41 | 46 | 50 | 55 | 60 | 65 | 70 | 75 | 80 |
| 6.78 | 7.78 | 9.78 | 12.73 | 15.73 | 17.73 | 20.67 | 23.67 | 26.67 | 29.67 | 33.38 | 35.38 | Grade A not applicable to these dia’s | |||||||||
| 6.64 | 7.64 | 9.64 | 12.57 | 15.57 | 17.57 | 20.16 | 23.16 | 26.16 | 29.16 | 33 | 35 | 40 | 45 | 49 | 53.8 | 58.8 | 63.1 | 68.1 | 73.1 | 78.1 | |
| Head Thickness (K) Tol + or – Grade A Grade B |
2.8 | 3.5 | 4 | 5.3 | 6.4 | 7.5 | 8.8 | 10 | 11.5 | 12.5 | 14 | 15 | 17 | 18.7 | 21 | 22.5 | 25 | 26 | 28 | 30 | 33 |
| Major Dia at thread (min) | 3.838 | 4.826 | 5.794 | 7.76 | 9.732 | 11.701 | 13.682 | 15.682 | 17.623 | 19.623 | 21.623 | 23.577 | 26.577 | 29.522 | 32.522 | 35.465 | 38.465 | 41.437 | 44.437 | 47.399 | 51.399 |
| Major Dia at thread (max) | 3.978 | 4.976 | 5.974 | 7.972 | 9.968 | 11.966 | 13.962 | 15.962 | 17.958 | 19.958 | 21.958 | 23.952 | 26.952 | 29.947 | 32.947 | 35.94 | 38.94 | 41.937 | 44.937 | 47.929 | 51.929 |
| 0.125 | 0.15 | 0.18 | 0.215 | Grade A not applicable to these dia’s | |||||||||||||||||
| 0.2 | 0.24 | 0.29 | 0.35 | 0.42 | 0.5 | ||||||||||||||||
| Across corners e Min Grade A Min Grade B |
7.66 | 8.79 | 11.05 | 14.38 | 17.77 | 20.03 | 23.36 | 26.75 | 30.14 | 33.53 | 37.72 | 39.98 | Grade A not applicable to these dia’s | ||||||||
| 7.5 | 8.63 | 10.89 | 14.2 | 17.59 | 19.85 | 22.78 | 26.17 | 29.56 | 32.95 | 37.29 | 39.55 | 45.2 | 50.85 | 55.37 | 60.79 | 66.44 | 71.3 | 76.95 | 82.6 | 88.25 | |
ASME SF568 12.9 Hex Nut Mechanical Properties
Verify 12.9 hex nut proof load, hardness, and strength values. Matching nut properties preserve joint integrity with 12.9 bolts.
| Nominal thread diameter size range [mm] | Proof strength [MPa] | Yield strength (min) [MPa] | Tensile strength (min) [MPa] | Hardness [Rockwell] |
|---|---|---|---|---|
| 1.6–100 | 970 | 1100 | 1220 | C39–44 |
Chemical Properties of Allen Bolt 12.9
Review 12.9 allen bolt chemistry for hardenability and strength. Consistent composition supports tensile, yield, and toughness targets.
| Carbon Steel 12.9 | C | P | S | B |
|---|---|---|---|---|
| 0.28-0.5 | 0.025 | 0.025 | 0.003 |
Torque Chart of Grade 12.9 Bolt
Apply the recommended grade 12.9 bolt torque by size and pitch. Correct torque achieves preload without risking thread damage.
| Class 12.9 Bolt Diameter x Pitch | Thread Stress Area mm2 |
*When μ = 0.10 Results in: |
*When μ = 0.14 Results in: |
||
|---|---|---|---|---|---|
| Tightening Bolt Torque Nm |
Pre-load kN |
Tightening Bolt Torque Nm |
Pre-load kN |
||
| M5 x 0.8 | 14.2 | 8.9 | 12.7 | 11.2 | 12.0 |
| M6 x 1 | 30.1 | 15.4 | 17.9 | 19.3 | 17.0 |
| M8 x 1.25 | 36.6 | 37.2 | 32.8 | 46.9 | 31.1 |
| M10 x 1.5 | 58.0 | 73 | 52.1 | 93 | 49.4 |
| M12 x 1.75 | 84.3 | 126 | 75.9 | 160 | 72.0 |
| M14 x 2 | 115 | 201 | 104.1 | 255 | 98.9 |
| M16 x 2 | 157 | 309 | 142.4 | 395 | 135.4 |
| M18 x 2.5 | 192 | 432 | 174 | 549 | 165 |
| M20 x 2.5 | 245 | 605 | 223 | 773 | 212 |
| M22 x 2.5 | 302 | 824 | 277 | 1057 | 264 |
| M24 x 3 | 353 | 1041 | 320 | 1329 | 305 |
| M27 x 3 | 459 | 1526 | 420 | 1959 | 400 |
| M30 x 3.5 | 561 | 2077 | 511 | 2662 | 487 |
| M33 x 3.5 | 694 | 2799 | 635 | 3601 | 605 |
| M36 x 4 | 817 | 3607 | 747 | 4631 | 711 |
| M39 x 4 | 976 | 4652 | 895 | 5994 | 853 |
Grade 12.9 Bolts, Screws, Threaded Rod & Washers Price List
See current prices for 12.9 bolts, screws, threaded rod, and washers. Rates vary by size, finish, and quantity. Request a quote for bulk.
| High Tensile class 12.9 Fasteners Price List | Price |
|---|---|
| m16 gr 12.9 hex socket head cap bolt | ₹ 7.04-₹ 10.49 / Piece |
| 12.9 Gr. high strength hexagonal screw M2 | ₹ 0.7058-₹ 7.04 / Ton |
| Allen Bolt Hexagon Socket din912 Cap Head class 12.9 | ₹ 91.35 / Kilograms |
Frequently Asked Questions About Grade 12.9 Bolt
What does 12.9 mean on a bolt?
Grade 12.9 means an alloy steel bolt with a tensile strength of 1200 MPa and yield strength 90% of tensile (1080 MPa). It is heat-treated for high strength and fatigue resistance in demanding applications.
Is a 12.9 bolt stronger than grade 8?
Yes, grade 12.9 bolts are stronger than grade 8, with tensile strength around 1200 MPa vs. about 800 MPa for grade 8, making 12.9 suitable for extreme load and critical connections.
What is 12.9 grade material?
Grade 12.9 material is quenched and tempered alloy steel with high carbon content, providing superior hardness, tensile strength, and fatigue resistance for heavy-duty fasteners.
What is the capacity of a 12.9 bolt?
A 12.9 bolt has a minimum tensile strength of 1200 MPa and yield strength of approximately 1080 MPa, supporting heavy structural loads and high-stress environments.
Where are 12.9 bolts used?
Used in automotive, aerospace, heavy machinery, and structural engineering, 12.9 bolts are ideal for applications requiring maximum strength and resistance to fatigue and vibration.