Get a quote

Carbon Steel Bolts

  • Home
  • Carbon Steel Bolts
Manufacturer, Exporter & Supplier of Carbon Steel Bolts

High-Strength Carbon Steel Bolts for Industrial & Structural Applications

Carbon Steel Bolts are essential threaded fasteners designed to provide reliable clamping force in structural, mechanical, and heavy-duty assemblies. Manufactured from low, medium, or high carbon steel, these bolts deliver a balance of strength, machinability, and cost-efficiency across a wide range of applications. They are typically produced in accordance with standards such as ASTM A307, ASTM A325, ISO 898-1, and DIN 931/933, ensuring consistent mechanical performance and dimensional accuracy.

Carbon Steel Bolts Manufacturer

Used extensively in construction, oil & gas, power generation, and general engineering industries, carbon steel bolts serve as the backbone of load-bearing connections. Depending on the grade and heat treatment, they can withstand high tensile loads and dynamic stress conditions. KK Fasteners supplies these bolts to global markets with full material traceability, supporting both standard and project-specific requirements.

Technical Specification List Of Carbon Steel Bolts

Parameter Details
Material Low Carbon Steel, Medium Carbon Steel, High Carbon Steel
Grades ASTM A307, ASTM A325, ASTM A490, ISO 898-1 (Class 4.6, 8.8, 10.9)
Size Range M6 to M100 / 1/4" to 4"
Thread Type Metric, UNC, UNF, BSW
Standards DIN 931, DIN 933, ISO 4014, ISO 4017, ASTM, BS, JIS
Surface Finish Black Oxide, Zinc Plated, Hot Dip Galvanized (HDG), Phosphate Coated
Types Hex Bolts, Heavy Hex Bolts, Stud Bolts, Anchor Bolts
Tensile Strength 400 MPa to 1040 MPa (depending on grade)
Hardness 120 HV to 320 HV

Carbon Steel Hex Bolt Chemical Composition

BS 970: 1955 Chemical Composition
Carbon Silicon Manganese Nickel Chromium Molybdenum sulphur Phosphorus
EN3B 0.25Max 0.35Max 1.0Max – – – 0.06Max 0.06Max
EN1A 0.07/0.15 0.10Max. 0.80/1.20 – – – 0.20/0.30 0.07Max
EN8 0.35/0.45 0.05/0.35 0.60/1.00 – – – 0.06Max 0.06Max
EN9 0.50/0.60 0.05/0.35 0.50/0.80 – – – 0.06Max 0.06Max
EN16 0.30/0.40 0.10/0.35 1.30/1.80 – – 0.20/0.35 0.05Max 0.05Max
EN19 0.35/0.45 0.10/0.35 0.50/0.80 – 0.90/1.50 0.20/0.40 0.05Max 0.05Max
EN24 0.35/0.45 0.10/0.35 0.45/0.70 1.30/1.80 0.90/1.40 0.20/0.35 0.05Max 0.05Max

Mechanical Behaviour Carbon Steel J Type Anchor Bolt

Grade Material Tensile Strength MPa min. Proof Strength MPa min. Core Rockwell Hardness Yield Strength MPa min.
Min. Max.
4.6 Low or Medium Carbon Steel 400 225 B67 B99.5 240
8.8 Medium Carbon Steel Q+T 800830 580600 C22C23 C32C34 640660

Carbon Steel Hex Bolts Dimensions

Hex Bolt Dimension

All measurements in millimeters

NOMINAL SIZE (D)
BODY DIAMETER
BOLT HEAD THICKNESS
ACROSS THE FLATS
ACROSS CORNERS
D (MAX)
D (MIN)
H (MAX)
H (MIN)
F (MAX)
F (MIN)
C (MAX)
C (MIN)
m10
10.00
9.78
6.63
6.17
17.00
15.73
18.48
17.77
m12
12.00
11.73
7.76
4.24
19.00
17.73
20.78
20.03
m14
14.00
13.73
9.09
8.51
22.00
20.67
24.25
23.35
m16
16.00
15.73
10.32
9.68
24.00
23.67
27.71
26.75
m20
20.00
19.67
12.88
12.12
30.00
29.16
34.64
32.95
m24
24.00
23.67
15.44
14.56
36.00
35.00
41.57
39.55
m30
30.00
29.67
19.48
17.92
46.00
45.00
53.12
50.85
m36
36.00
35.61
23.38
21.63
55.00
53.80
63.51
60.79
m42
42.00
41.38
26.97
25.03
65.00
62.90
75.06
71.71
m48
48.00
47.38
31.07
28.93
75.00
72.60
86.60
82.76
m56
56.00
55.26
36.2
33.80
85.00
82.20
98.15
93.71
m64
64.00
63.26
41.32
38.68
95.00
91.80
109.70
104.65
m72
72.00
71.26
46.45
43.55
105.00
101.40
121.24
115.60
m80
80.00
79.26
51.58
48.42
115.00
111.00
132.72
126.54
m90
90.00
89.13
57.74
54.26
130.00
125.50
150.11
143.07
m100
90.00
99.13
63.9
60.10
145.00
140.00
167.43
159.60

Carbon Steel Bolts Weight Chart

MM THREADS AS PER IS 1363/67
APPROXIMATE WEIGHT IN KGS FOR 100 NOS
LENGTH DIAMETER
M 5 M 6 M 8 M 10 M 12 M 14 M 16 M 18 M 20 M 22
16 mm 0.448 0.743 1.590 3.211
20 mm 0.598 0.812 1.711 3.411 4.892
25 mm 0.660 0.897 1.871 3.660 5.252 8.170
30 mm 0.737 1.010 2.070 3.912 5.574 9.690 10.707 18.657
35 mm 0.804 1.120 2.271 4.223 5.974 10.000 11.416 16.026 19.608
40 mm 0.881 1.230 2.470 4.533 6.410 10.288 12.107 16.667 20.747
45 mm 0.958 1.340 2.671 4.840 6.859 10.504 12.821 17.241 21.739
50 mm 1.030 1.450 2.870 5.155 7.299 11.261 13.624 17.857 22.727 28.409
55 mm 1.560 3.071 5.464 7.740 11.628 14.409 18.868 23.810 30.120
60 mm 1.670 3.270 5.774 8.183 12.255 15.244 20.000 25.126 32.051
65 mm 1.781 3.472 6.083 8.621 12.626 16.026 21.008 26.455 34.014
70 mm 1.890 3.671 6.394 9.058 12.987 16.835 22.124 27.778 35.461
75 mm 2.000 3.873 6.702 9.506 13.228 17.606 23.256 29.070 39.063
80 mm 2.111 4.072 7.013 10.000 13.889 18.248 24.510 30.303 40.000
90 mm 4.472 7.634 10.917 14.925 19.841 26.042 33.113 41.667
100 mm 4.873 8.251 11.820 16.340 21.459 27.778 35.714 46.296
110 mm 8.881 12.723 17.730 23.041 31.250 38.168 47.170
120 mm 9.506 13.624 18.797 24.631 32.895 40.984 50.000
130 mm 10.101 14.535 20.000 26.316 34.722 43.478 52.632
140 mm 10.707 15.432 20.833 27.933 35.461 46.296 55.556
150 mm 11.312 16.340 22.222 29.412 37.594 48.544 58.824
160 mm 11.905 17.241 24.272 31.056 40.984 50.505 61.728
170 mm 12.500 18.116 32.680 53.191 64.935
180 mm 13.123 19.011 26.882 34.247 55.556 67.568
190 mm 13.736 19.920 35.971 58.140 70.423
200 mm 14.327 20.833 29.586 37.594 49.020 60.976 73.529
220 mm 15.528 22.624 40.650 65.789 79.365
240 mm 16.722 24.510 43.860 71.429 84.746
250 mm 17.301 25.381 45.455 74.627 87.719
260 mm 17.921 26.316 47.170 76.923 90.909
280 mm 19.157 28.090 50.505 81.967 98.039
300 mm 20.325 29.940 53.763 87.719 104.167
320 mm 31.646 56.818 92.593
340 mm 33.557 60.241 98.039
360 mm 35.211 63.291 104.167
380 mm 37.037 66.667 108.696
400 mm 39.063 69.444 113.636

Grades of Carbon Steel Bolts

  • Carbon Steel AISI 1018 Bolts
  • Carbon Steel AISI 1020 Bolts
  • Carbon Steel AISI 1040 Bolts
  • Carbon Steel AISI 1045 Bolts

Different Types of Carbon Steel Bolts

  • Carbon Steel Flanged Bolts
  • Carbon Steel Hex Bolts
  • Carbon Steel U Bolts
  • Carbon Steel Shoulder Bolts
  • Carbon Steel Eye Bolts
  • Carbon Steel Heavy Hex Bolts
  • Carbon Steel Hollow Hex Bolts
  • Carbon Steel Hollow Allen Bolts
  • Carbon Steel Machine Bolts
  • Carbon Steel Socket Head Bolts
  • Carbon Steel Hex Flange Bolts
  • Carbon Steel Lag Bolts
  • Carbon Steel J Bolts
  • Carbon Steel Elevator Bolts
  • Carbon Steel Hanger Bolts
  • Carbon Steel Carriage Bolts
  • Carbon Steel Allen Bolts
  • Carbon Steel Anchor Bolts
  • Carbon Steel Countersunk Bolts
  • Carbon Steel Stud Bolts
  • Carbon Steel Square Head Bolts
  • Carbon Steel Stud Bolts
  • Carbon Steel Full Threaded Stud Bolts
  • Carbon Steel Tap End Stud Bolts
  • Carbon Steel Double End Stud Bolts
  • Carbon Steel Reduced Shank Stud Bolts
  • Carbon Steel Flange Bolting Stud Bolts
  • Carbon Steel Weld Studs
  • Carbon Steel Threaded Rods
  • Carbon Steel Hex Head Bolts
  • Carbon Steel Jack Bolts
  • Carbon Steel Structural Bolts
  • Carbon Steel Step Bolts
  • Carbon Steel Square Head Machine Bolts
  • Carbon Steel Plow Bolts
  • Carbon Steel Metric Bolts
  • Carbon Steel Hex Tap Bolts
  • Carbon Steel Hex Machine Bolts
  • Carbon Steel Shoulder Eye Bolts
  • Carbon Steel Serrated Flange Bolts
  • Carbon Steel Turned Eye Bolts
  • Carbon Steel Long Bolts
  • Carbon Steel Bent Bolts
  • Carbon Steel Square U Bolts
  • Carbon Steel Timber Bolts
  • Carbon Steel 15 Point Flange Bolts
  • Carbon Steel Button Head Bolts
  • Carbon Steel Hexagon Flange Bolts
  • Carbon Steel Stud Bolts
  • Carbon Steel Hexagon Head Bolts
  • Carbon Steel Lifting Eye Bolts
  • Carbon Steel T Bolts
  • Carbon Steel Threaded Bolts

Key Technical Features

  • Engineered to deliver tensile strength up to 1040 MPa (Class 10.9), enabling secure fastening in high-load structural assemblies such as bridges and steel frameworks.
  • Precision-machined threads conform to ISO and UNC/UNF standards, ensuring consistent fitment and reduced risk of thread stripping during installation.
  • Available with hot dip galvanizing (HDG) up to 70 microns, providing enhanced corrosion resistance for outdoor and marine environments.
  • Controlled heat treatment processes improve hardness and fatigue resistance, making these bolts suitable for cyclic loading conditions.
  • Tight dimensional tolerances as per DIN/ISO specifications ensure interchangeability across global projects and assemblies.
  • Versatile coating options such as zinc plating and phosphate coating reduce friction during tightening and improve installation efficiency.
  • Optimized carbon composition allows a balance between ductility and strength, minimizing brittleness under impact loads.
  • Suitable for both static and dynamic applications, including vibration-prone environments when paired with appropriate locking systems.

Industry Applications

Carbon Steel Bolts are widely used in industries requiring strong, reliable fastening solutions for structural and mechanical assemblies.

  • Structural Steel Construction — Used in beam-to-column connections and load-bearing joints in buildings and infrastructure projects.
  • Oil & Gas Pipelines — Secures flanges and pressure-containing components exposed to mechanical stress.
  • Power Plants — Applied in turbine assemblies, boilers, and support structures where high tensile strength is critical.
  • Automotive Manufacturing — Used in chassis assembly, suspension systems, and engine mounting applications.
  • Heavy Machinery — Provides fastening in equipment frames subjected to vibration and dynamic loads.
  • Railway Infrastructure — Used in track systems and rolling stock components requiring high durability.
  • Marine Structures — HDG-coated bolts are used in docks and offshore platforms to resist corrosion.
  • Industrial Equipment Fabrication — Integral in assembling process equipment and structural frames.

Manufacturing & Quality Assurance

Carbon steel bolts are typically produced through cold forging or hot forging depending on size and grade, followed by thread rolling for enhanced surface strength. Heat treatment processes such as quenching and tempering are applied to achieve desired mechanical properties.

Quality assurance includes dimensional inspection using calibrated gauges, tensile and hardness testing as per ASTM and ISO standards, and coating thickness verification for plated or galvanized finishes. Each batch is traceable through material test certificates (MTCs). KK Fasteners follows ISO 9001-certified processes, ensuring consistency across high-volume production and export orders.

img
Icon

Wide Range of Quality Products

Explore our comprehensive range of products, ensuring you find the perfect solution for your specific requirements.

img
Icon

Competitive Pricing and Cost Savings

Save money without compromising on quality, thanks to our competitive prices and cost-effective options.

img
Icon

Exceptional Customer Service

Personalized assistance, prompt responses, and a commitment to meeting your needs, making your purchase process seamless.

Send us your Requirement for Carbon Steel Bolts

We can assure you one of best prices in the Industry. We respond to all enquiries with in 4-8 hours on all business days. Send us your requirement on inquiry@kkfasteners.com
Send Us Your Requirement
Contact

Carbon Steel Bolts - FAQs

Carbon steel bolts are threaded fasteners manufactured from steel with varying carbon content, designed to provide strong and durable connections in structural and mechanical assemblies. They are widely used due to their strength, cost-effectiveness, and availability in multiple grades and standards.

Carbon steel bolts derive their strength primarily from carbon content, while alloy steel bolts contain additional elements such as chromium, molybdenum, or nickel. These alloying elements improve corrosion resistance, heat resistance, and mechanical performance in extreme environments.

Carbon steel bolts are commonly manufactured according to standards such as ASTM A307, ASTM A325, ASTM A490, ISO 898-1, and DIN 931/933. These standards define mechanical properties, dimensions, tolerances, and testing requirements to ensure consistent performance.

Selecting the right bolt depends on load requirements, environmental exposure, and compatibility with mating components. High tensile grades like 8.8 or 10.9 are suitable for structural applications, while galvanized or coated bolts are preferred for outdoor or corrosive environments.

A reliable supplier should offer ISO-certified manufacturing, compliance with international standards, and full material traceability. KK Fasteners supports global buyers with consistent quality, documented inspections, and export experience across multiple industries.

Carbon Steel Bolts - Export Destination

Carbon Steel Bolts Supplier in North America
Antigua and Barbuda, Bahamas, Barbados, Belize, Canada, Costa Rica, Cuba, Dominica, Dominican Republic, El Salvador, Grenada, Guatemala, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Trinidad and Tobago, United States.
Carbon Steel Bolts Supplier in South America
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Falkland Islands, French Guiana, Guyana, Paraguay, Peru, Suriname, Uruguay, Venezuela.
Carbon Steel Bolts Supplier in Europe
Albania, Andorra, Austria, Belarus, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Czech Republic (Czechia), Denmark, Estonia, Finland, France, Germany, Greece, Holy See, Hungary, Iceland, Ireland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Moldova, Monaco, Montenegro, Netherlands, North Macedonia, Norway, Poland, Portugal, Romania, Russia, San Marino, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Ukraine, United Kingdom.
Carbon Steel Bolts Supplier in Asia
Afghanistan, Armenia, Azerbaijan, Bahrain, Bangladesh, Bhutan, Brunei, Cambodia, Cyprus, Georgia, India, Indonesia, Iran, Iraq, Israel, Japan, Jordan, Kazakhstan, Kuwait, Kyrgyzstan, Laos, Lebanon, Malaysia, Maldives, Mongolia, Myanmar, Nepal, Oman, Pakistan, Palestine, Philippines, Qatar, Saudi Arabia, Singapore, South Korea, Sri Lanka, State of Palestine, Syria, Taiwan, Tajikistan, Thailand, Timor-Leste, Turkey, Turkmenistan, United Arab Emirates, Uzbekistan, Vietnam, Yemen.
Carbon Steel Bolts Supplier in Australia
Australia, Fiji, Kiribati, Marshall Islands, Micronesia, Nauru, New Zealand, Palau, Papua New Guinea, Samoa, Solomon Islands, Tonga, Tuvalu, Vanuatu.

Carbon Steel Bolts remain a core component in structural and industrial fastening, where strength, reliability, and compliance with international standards are critical. With controlled manufacturing processes and global distribution capability, KK Fasteners supports project-specific requirements with precision-engineered solutions. For technical assistance, custom specifications, or bulk pricing, request a quote or connect with the engineering team today.

request a quote
email us

Bolts Materials

Our Products

Types of Fasteners

download brochure