High Tensile Bolts

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High tensile bolts are designed for applications where strength, reliability and load bearing performance are critical. They are commonly used in construction, engineering, fabrication and industrial environments where standard bolts would not provide sufficient performance.


At Duchy Fasteners, a comprehensive range of high tensile bolts is held in stock to support demanding applications across Cornwall and the wider UK. Customers can purchase directly from the trade counter or order online for fast courier delivery, ensuring dependable access to structural grade fixings when they are needed most.

What Are High Tensile Bolts?

High tensile bolts are manufactured from carbon steel that has been heat treated to achieve increased tensile strength. This process allows the bolt to withstand greater loads and higher stress levels compared to standard steel fasteners.


These bolts are classified by strength grades, which indicate their mechanical performance. The most commonly used grades are 8.8, 10.9 and 12.9, each suited to different structural and engineering requirements.


High tensile bolts are specified where safety, structural integrity and long term performance are essential.

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High Tensile Bolts Held in Stock

Duchy Fasteners stocks a practical and industry focused range of high tensile bolts suitable for a wide variety of applications.

The high tensile range includes:


  • High tensile hex bolts

  • High tensile set bolts

  • Structural bolts for load bearing assemblies

  • Matching high tensile nuts

  • Hardened washers to suit high tensile applications

These fasteners are available in multiple metric sizes and thread configurations, allowing customers to source complete fastening solutions from one specialist supplier.

High Tensile Bolt Grades Explained

Understanding bolt grades is essential when selecting high tensile fasteners.


Grade 8.8 bolts are commonly used in construction and general structural applications where strong and reliable performance is required.


Grade 10.9 bolts offer increased tensile strength and are typically specified for heavy engineering, machinery and high load assemblies.


Grade 12.9 bolts provide the highest strength in this category and are used in applications where maximum performance is essential, such as precision engineering and heavily stressed components.


Duchy Fasteners stocks high tensile bolts across these grades, allowing customers to specify accurately rather than over engineering or compromising on strength.

Typical Uses for High Tensile Bolts

High tensile bolts are used in applications where standard fasteners may fail under load. Common uses include structural steelwork, machinery assembly, agricultural equipment, automotive applications and heavy fabrication.


They are also widely used in infrastructure projects, plant installation and maintenance environments where reliability under stress is critical.


Correct specification ensures high tensile bolts deliver safe and long lasting performance.

Strength and Performance Benefits

The key advantage of high tensile bolts is their ability to withstand high loads without stretching or failing. This makes them suitable for joints subject to vibration, dynamic loads or continuous stress.


High tensile bolts maintain consistent clamping force, which helps prevent joint loosening over time. This performance is essential in safety critical and structural applications.


Selecting the correct grade and size ensures bolts perform as intended throughout their service life.

High Tensile Bolts for Trade and Industry

Duchy Fasteners supports builders, engineers, fabricators and maintenance teams by maintaining strong stock levels of high tensile bolts and associated components.


This ensures trade customers can source structural fixings quickly without delays caused by limited availability. Private customers also benefit from access to professional grade fasteners typically used by industry.

Trade Counter Supply in Cornwall

Customers can purchase high tensile bolts directly from the Duchy Fasteners trade counter at Cornwall Business Park. This allows customers to inspect products, confirm grades and sizes and collect fasteners immediately.


The trade counter service is ideal for urgent jobs, site work and projects where correct specification is essential. Knowledgeable staff are available to assist with selecting suitable high tensile bolts where required.

Online Ordering and UK Delivery

High tensile bolts are also available to order online with courier delivery across Cornwall and the rest of the UK. This supports customers working on multiple sites or managing projects outside the local area.


Online access to the same extensive stock range ensures consistent supply for repeat orders and national projects.

Why Choose Duchy Fasteners for High Tensile Bolts

Duchy Fasteners is a specialist supplier focused on fixings and fastenings rather than general building materials. This allows for deeper stock, wider grade availability and better technical understanding.


Customers choose Duchy Fasteners for reliable access to high tensile bolts in grades 8.8, 10.9 and 12.9, backed by flexible purchasing options and dependable service.

FAQs About High Tensile Bolts

What are high tensile bolts used for?

They are used in structural and engineering applications where high strength and load bearing performance are required.

What grades of high tensile bolts are available?

Duchy Fasteners stocks grades 8.8, 10.9 and 12.9.

Are high tensile bolts suitable for structural steelwork?

Yes, they are commonly specified for structural and load bearing assemblies.

Can I buy high tensile bolts locally in Cornwall?

Yes, high tensile bolts are available from the Duchy Fasteners trade counter in Scorrier.

Do you deliver high tensile bolts across the UK?

Yes, high tensile bolts can be ordered online and delivered nationwide.

How Does This Affect Your Project?

Choosing the correct high tensile bolts is essential for safety, durability and performance. By sourcing high tensile fasteners from Duchy Fasteners, customers gain access to specialist stock, accurate grades and reliable supply.


Whether working on construction, engineering or maintenance projects, Duchy Fasteners provides high tensile bolts that deliver strength where it matters most.