The Groundbreaking Solution for Better Bolt Torque Loads

In a perfect world, exactly the right amount of torque would get applied to threaded fasteners every time. That provides what you’re seeking – a strong, durable gasket seal.

But to tweak a line from The Rolling Stones, you haven’t always been able to get what you want. Traditional B7 studs widely used in the oil and gas industry demonstrate broad variations (up to 44%) in torque load.

Let’s dive into those torque load variations before getting to the game-changing solution.

Why K-Factor Is So Important

K-factor is a value for calculating the target input torque for your fastener. Also known as nut factor, it can be determined by doing experiments with the lubricant and fastener you plan to use.

K-factor testing is essential for PTFE bolts because there is no manufacturing standard in the industry for the coating applied to these fasteners. If there’s no experimental testing, the theoretical k-factor is more likely to be wrong.

When our team at Houston Fastener analyzed data from six different manufacturers, we found that the over-tapping process is inconsistent throughout the industry. The average k-factors ranged from 0.11 to 0.18 when dry. Lubricated, the average k-factors get far more consistent at 0.10 to 0.12, but they still have a wide bolt scatter of up to ±38% at a 95% confidence interval.

An incremental change in k-factor highly impacts applied torque. For example, if a plant decides to use a k-factor of 0.12 but should be using 0.18, they will be under torquing their studs by 33%. In this example, a major unaccounted-for loss in bolt stress directly affects the joint’s gasket stress and may result in a flange leak.

PROTINN: New Solution for Properly Torqued Fasteners

Finally, you can get what you need – better precision, performance and predictability with PTFE-coated studs. Introducing PROTINN, the all-new bolt with Xylan 1424 purple coating that offers an unmatched ±10% k-factor for 3-4 times better torque loads than other B7 studs.

Our oil and gas industry experts at Houston Fastener developed PROTINN to deliver consistent and repeatable bolt loads on your flange assemblies. Now you can confidently take on your toughest jobs with a stud that provides greater safety and performance.

PROTINN’s best-in-class benefits include:

• Consistent accuracy for a better torque-tension relationship
• Superior corrosion resistance (7P/0.3% red rust rating)
• Exact stud load with zero underloading concerns
• Single-source manufacturing and in-house testing

In our study of 700 studs ranging from 5/8” to 1-1/4”, PROTINN studs were the most accurate and consistent, showing the same k-factor (0.12) when dry and lubricated. The results demonstrate that an effective and consistent manufacturing process for PTFE-coated studs lead to a low k-factor and a more consistent thread contact surface geometry.

PROTINN enables you to worry less about downtime, costly equipment failures and missed deadlines. It’s not just another bolt – it’s redefining precision fastening to help you achieve the best bolt load.

Ready to put the power of purple to work for you? Talk with an oil and gas expert from Houston Fastener to discuss how PROTINN can benefit your next project.