A325 High Strength Heavy Hex Structural Bolts
A325 High Strength Heavy Hex Structural Bolts are designed for structural steel connections where high strength, durability and reliable performance are required. These bolts feature a heavy hex head design that provides better load distribution and improved tightening efficiency, making them suitable for demanding construction and industrial applications. Manufactured according to A325 specifications, they are widely recognized for their excellent mechanical properties and dependable performance.
These high strength structural bolts are commonly used in steel buildings, bridges, infrastructure projects and heavy equipment applications. With precise dimensions, consistent thread quality and strict quality control throughout the production process, A325 Heavy Hex Structural Bolts provide secure and long-lasting fastening solutions for critical structural assemblies.


Specification:
A325 heavy hex bolts are high-strength structural bolts commonly used in construction. They typically have a medium carbon or alloy steel composition. The ASTM A325 standard outlines specifications for these bolts, including size range, mechanical properties, and testing requirements. They’re designed for use in structural connections and have a defined thread length and heavy hexagonal head for enhanced load-bearing capacity.
| Product name | ASTM A325 Heavy Hex Bolts |
|---|---|
| Diameter | 1/2″ – 1-1/2″ |
| Dimension Standard | ASME B18.2.6 |
| Head Type | Heavy Hex Head |
| Bolt Length | 1-1/2"-10" |
| Class | Type 1 |
| Hardness | 25-34HRC |
| Tension Strength | 120 ksi |
| Material | C45/40Cr/AISI4140 |
| Compatible nuts/washers | A563 DH Heavy Hex Nut/F436 Washer |
| Surface treatment | Black Oxide Coating/Zinc Plating /Hot-Dip Galvanizing/Dacromet Coating |
Mechanical property:
| Specification | Tensile | Yield | Elongation % | Reduction Area % | Hardness (HRC) |
| A325 Type 1 Bolts | 120 ksi (min) | 92 ksi(min) | 14 (min) | 35 (min) | 25-34 |
Chemical Composition:
| Chemical Elements | Composition % |
|---|---|
| Carbon | 0.30-0.52 |
| Manganese | 0.60 min |
| Phosphorus | 0.035 max |
| Sulfur | 0.040 max |
| Silicon | 0.15 – 0.30 |
| Boron | 0.003 max |
Dimension Chart:
The dimension chart of A325 Heavy Hex Bolts provides detailed specifications including nominal diameter, thread pitch, body diameter, head width across flats, head height and other critical dimensions. These dimensional requirements help ensure proper fit, compatibility and reliable performance in structural fastening applications.
The following table shows the standard dimensions of A325 Heavy Hex Bolts for different sizes. Please refer to the chart for accurate measurements when selecting bolts for steel structures, construction projects and other heavy-duty applications.

| Mon | 1/2 | 5/8 | 3/4 | 7/8 | 1 | 1-1/8 | 1-1/4 | 1-3/8 | 1-1/2 |
| P | 13 | 11 | 10 | 9 | 8 | 7 | 7 | 6 | 6 |
| ds max | 0.515 | 0.642 | 0.768 | 0.895 | 1.022 | 1.149 | 1.277 | 1.404 | 1.531 |
| ds min | 0.482 | 0.605 | 0.729 | 0.852 | 0.976 | 1.098 | 1.223 | 1.345 | 1.47 |
| k max | 0.323 | 0.403 | 0.483 | 0.563 | 0.627 | 0.718 | 0.813 | 0.878 | 0.974 |
| k min | 0.302 | 0.378 | 0.455 | 0.531 | 0.591 | 0.658 | 0.749 | 0.81 | 0.902 |
| s max | 0.875 | 1.062 | 1.25 | 1.438 | 1.625 | 1.812 | 2 | 2.188 | 2.375 |
| s min | 0.85 | 1.031 | 1.212 | 1.394 | 1.575 | 1.756 | 1.938 | 2.119 | 2.3 |
| r max | 0.031 | 0.062 | 0.062 | 0.062 | 0.093 | 0.093 | 0.093 | 0.093 | 0.093 |
| r min | 0.009 | 0.021 | 0.021 | 0.031 | 0.062 | 0.062 | 0.062 | 0.062 | 0.062 |
- RELATED BOLTS LISTS:
- HEX BOLTS
- HEAVY HEX BOLTS
- DIN931 HEX BOLTS
- AS1252 HEX BOLTS
- DIN6914 HEX BOLTS
- ASME B 18.2.1 HEX BOLTS
- DIN933 HEX BOLTS
- A490 HEAVY HEX BOLTS
- RELATED NUTS LIST:
- HEX NUTS
- HEAVY HEX NUTS
- ISO4032 HEX NUTS
- DIN934 HEX NUTS
- A194 HEAVY HEX NUTS
- A563 HEAVY HEX NUTS
- THREADED ROD LIST:
- DIN975 THREADED RODS
- A193 B7 STUD BOLTS
Production Process of A325 Heavy Hex Bolts:
The production process of A325 heavy hex structural bolts involves multiple precision manufacturing steps, including raw material preparation, cold forging or hot forging, thread rolling, heat treatment, surface treatment and final inspection. Each process is carefully controlled to ensure accurate dimensions, required mechanical properties and consistent performance according to A325 requirements.
During manufacturing, key factors such as bolt dimensions, thread accuracy, tensile strength, hardness and surface quality are strictly inspected. Advanced production equipment and quality control procedures help ensure that A325 Heavy Hex Structural Bolts provide reliable strength and durability for structural steel connections, construction projects and other demanding applications.
Quality control:
Quality control of A325 heavy hex bolts, which are typically high-strength structural bolts used in construction, involves rigorous measures to ensure they meet industry standards. Here are some key aspects of quality control:
| Control Method | Detail |
|---|---|
| Material Inspection: | Verify the material's composition, heat treatment, and quality upon receipt. Conduct metallurgical analysis to ensure the material properties meet the standards. |
| Process Control: | Implement strict process control measures for heat treatment, machining, threading, and any other manufacturing steps. Maintain consistent process parameters to ensure uniform quality. |
| Inspection Points: | Introduce inspection points at various stages of manufacturing to check for defects, dimensions, and quality. Inspect threading, dimensions, surface finish, and other critical parameters. |
| Sampling and Testing: | Regularly sample products for testing, such as tensile testing, hardness testing, and metallurgical analysis, to ensure they meet the required specifications. |
| Thread Inspection: | Thoroughly inspect threading using proper thread gauges to ensure accurate dimensions and fit with mating components. |
| Traceability: | Implement a traceability system to track each fasteners journey from raw material to final product. This aids in accountability and recalls if necessary. |
Application:
A325 Heavy Hex Structural Bolts are widely used in various structural and industrial applications where high strength and reliable connections are required, including:
* Steel building structures
* Bridges and infrastructure projects
* Industrial plants and equipment structures
* Steel frames and large construction projects
* Towers, warehouses and heavy-duty structures
* Transportation and energy-related facilities
Due to their high strength, heavy hex head design and excellent load-bearing capability, A325 Structural Bolts are suitable for critical bolted connections in demanding environments. They provide secure and durable fastening solutions where structural stability and long-term reliability are essential.
FAQ:
1.What’s the price of type1 of A325 heavy hex bolts?
The wholesale price of A325 heavy hex bolts is 1300-1800usd/ton. The material price of steel will fluctuate frequently, and the price is different for different surface treatment/quantity, so please send the inquiry to our email for the specific price. Emai: info@china-bolts.com
2.How many days does it take you to produce a container of bolts?
Our daily production capacity of cold heading and hot forging bolts is about 30 tons, but due to the arrangement of materials, heat treatment, surface treatment, order scheduling takes time. The average delivery time of bolts for a container is 30-40 days.
3.What countries do you export A325 heavy hex bolts to?
We mainly export A325 heavy duty bolts to USA, Brazil, Argentina. The main service customers are medium and large fastener dealers, wholesalers, our company generally does not serve the end customer. Our company has stable customers in Ohio, Texas, South Carolina, Indiana, California, and Michigan in the United States.
4. Do you have a minimum order quantity requirement?
Yes, the MOQ we usually produce is about one ton.
