We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is a Superbolt?

By Dorothy Distefano
Updated May 17, 2024
Our promise to you
WiseGeek is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At WiseGeek, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

A superbolt is a special type of mechanical fastener that is used to replace hex nuts, bolts, and other threaded fasteners. This type of bolt is normally used with larger nuts and bolts, typically greater than 1 inch (25 cm) in diameter, which require a high amount of force to properly tighten. By using a superbolt, the force required to tighten a large fastener over several smaller bolts is spread, so that simple hand tools may be used. This provides an alternative to using large tools, like hydraulic wrenches and sledgehammers, which are difficult to handle and can pose safety risks.

A superbolt is made up of three primary components. The first is a hardened washer that provides a precision flat surface for smaller bolts to push against. The second is the round-nut body, which is threaded onto the bolt and sits against the washer. The third is a series of smaller bolts, known as jackbolts, which are threaded through the nut body and are tightened. When the jackbolts are tightened, they push against the hardened washer surface and secure the mechanical joint by placing the existing nut or bolt in pure tension.

Superbolts are normally used for large-scale equipment applications that require very high forces or pressures. A few examples include mechanical presses, where large diameter columns are used to distribute extremely high working loads, and steam turbines, which generate very high internal pressure that must be contained without leakage using metal-to-metal mechanical joints. The force necessary to properly tighten these fasteners becomes very difficult to achieve without large, cumbersome tools that can pose significant safety hazards.

There is a wide variety of superbolts available to meet many different applications. Guidelines are available through superbolt manufacturers to help customers select the correct size and type of superbolt for a specific set of operating conditions. These guidelines include the type of mechanical connection, operating temperature, working loads, and material consideration. Superbolts can also be custom-designed and fabricated to meet unique equipment applications.

Use of a superbolt can provide significant time-savings when compared to other mechanical fastening methods because only hand tools are used and worker safety is improved. Since a superbolt generates pure tension force when tightened, it also eliminates problems with seizing and thread galling that can occur with conventional fasteners. While effective, superbolts are more expensive than standard mechanical fasteners, and the cost-versus-benefit of their use should be evaluated for each specific application.

WiseGeek is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.