Aug 2025
Stud Bolts vs. Hex Bolts: Where and When to Use Them
Bolts are one of the most essential fasteners used in industries, construction, and machinery. Among the many types available, stud bolts and hex bolts are two of the most widely used. Both play an important role in holding equipment and structures together, but they are designed for different applications.
In this blog post, we will explain the difference between stud bolts and hex bolts, their advantages, and when to use each type. If you are looking for reliable fasteners, Pankaj International, a leading fastener manufacturer and exporter from India, can provide you with high-quality bolts for all your needs.
What are Stud Bolts?
A stud bolt is a threaded rod without a head. It usually comes with threads on both ends, and sometimes the full length is threaded. Stud bolts are used with two nuts to fasten flanges or other equipment. They provide strong clamping and are very popular in the oil, gas, and petrochemical industries.
Key Features of Stud Bolts:
• No head, only threaded rod.
• Available in fully threaded or partially threaded designs.
• Always used with two nuts (one on each side).
• Commonly used in flange connections and high-pressure environments.
Common Applications of Stud Bolts:
• Flange connections in pipelines.
• Pressure vessels and reactors.
• Refineries and chemical plants.
• Power plants and offshore drilling platforms.
What are Hex Bolts?
A hex bolt, also called a hex cap screw, has a hexagonal (six-sided) head with external threads. It is tightened using a wrench or spanner. Hex bolts are among the most common fasteners and are used in construction, machinery, automotive, and general engineering.
Key Features of Hex Bolts:
• Six-sided head for easy tightening.
• Available in full-threaded or half-threaded options.
• Simple design and widely available.
• Can be used with a nut or directly into a tapped hole.
Common Applications of Hex Bolts:
• Steel and concrete construction.
• Machinery assembly and maintenance.
• Automotive parts and vehicles.
• Bridges, buildings, and heavy equipment.
Stud Bolts vs. Hex Bolts – The Key Differences
While both stud bolts and hex bolts are used for fastening, they have very different designs and uses. Here are the main differences
| Feature |
Stud Bolt |
Hex Bolt |
| Design |
Threaded rod without head |
Six-sided head with threaded body |
| Tightening Method |
Tightened with two nuts |
Tightened with wrench or spanner |
| Applications |
Flanges, pipelines, high-pressure systems |
Construction, machinery, automotive |
| Strength |
Suitable for high temperature & pressure |
Suitable for general fastening needs |
| Reusability |
Can be replaced without disturbing flanges |
Removed and replaced as a whole unit |
| Cost |
Usually higher due to special use |
More economical and easily available |
When to Use Stud Bolts
Stud bolts are the preferred choice when:
• You are working with flanges in pipelines or reactors.
• The system is exposed to high pressure or high temperature.
• You need a secure and leak-proof joint.
• Equipment requires frequent maintenance and disassembly.
For example: In oil refineries and power plants, stud bolts are used to connect large diameter pipes and pressure vessels where safety is the top priority.
When to Use Hex Bolts
Hex bolts are the better choice when:
• You are working on construction projects like buildings, bridges, and steel structures.
• You need general-purpose fastening for machinery and equipment.
• A quick and easy installation is required.
• Cost-effective fasteners are needed for large quantities.
For example: In automotive manufacturing, hex bolts are widely used to assemble engines, chassis, and other vehicle components.
Advantages of Stud Bolts
• Provide uniform load distribution across the joint.
• Easier to remove for maintenance without damaging flanges.
• Suitable for critical environments like oil, gas, and chemical industries.
• Available in different grades and coatings for corrosion resistance.
Advantages of Hex Bolts
• Easy to use with standard tools.
• Widely available in different sizes and materials.
• Cost-effective for large projects.
• Versatile and suitable for many applications.
Choosing Between Stud Bolts and Hex Bolts
The choice between stud bolts and hex bolts depends on the application.
• If you are working with flanges, pipelines, or high-pressure systems, stud bolts are the right choice.
• If you need a general-purpose fastener for construction, machinery, or automotive work, hex bolts are more suitable.
Both types have their unique strengths, and using the right one ensures safety, durability, and efficiency.
Stud Bolts and Hex Bolts from Pankaj International
At Pankaj International, we manufacture and export a wide range of fasteners, including stud bolts, hex bolts, nuts, and washers. Our products are made from high-quality raw materials and meet international standards such as ISO, DIN, ASTM, and BS.
Why Choose Pankaj International?
• 30+ years of experience in fastener manufacturing.
• Wide range of industrial fasteners for global clients.
• High tensile strength and corrosion-resistant products.
• Timely delivery and competitive pricing.
Whether you need stud bolts for refinery projects or hex bolts for construction and machinery, we can provide fasteners tailored to your requirements.
Conclusion
Both stud bolts and hex bolts are essential in their own ways. Stud bolts are best for high-pressure, high-temperature, and critical applications like pipelines and flanges. Hex bolts, on the other hand, are versatile, affordable, and widely used in construction, machinery, and automotive industries.
Choosing the right bolt depends on the project’s requirements. At Pankaj International, we ensure that our clients get the right fasteners for their specific needs. If you are looking for a trusted stud bolt and hex bolt manufacturer in India, get in touch with us today.