When and Why to Use Hydraulic Bolt Tensioning

When and Why to Use Hydraulic Bolt Tensioning

When precision and safety meet heavy-duty demands, the right tools make all the difference. Hydraulic bolt tensioning offers a reliable way to ensure bolts are tightened correctly, making it a vital method for high-stress projects like wind turbines and pipelines. But how does it compare to traditional methods, and when should you use hydraulic bolt tensioning? 

What Is Hydraulic Bolt Tensioning?

Hydraulic bolt tensioning is a way to tighten bolts using hydraulic pressure to stretch them lengthwise. This method applies an exact, even force to the bolt, creating a strong hold without twisting. Compared to traditional methods, hydraulic tensioning is more accurate and reliable. This makes using a hydraulic bolt tensioner ideal for situations where secure joints are essential.

What Industries Benefit Most from Hydraulic Bolt Tensioning?

Hydraulic bolt tensioning finds extensive use in various industries, including:

  • Oil and gas – For critical pipeline flanges and pressure vessel closures
  • Power generation – In turbine assembly and maintenance
  • Aerospace – For critical structural joints in aircraft and spacecraft
  • Wind energy – In wind turbine assembly and maintenance
  • Mining – For heavy equipment assembly and maintenance
  • Petrochemical – In reactor vessel closures and heat exchanger maintenance

When Should You Use Hydraulic Bolt Tensioning?

Are You Working with Critical Joints?

Hydraulic bolt tensioning is often the go-to method for applications where joint integrity is non-negotiable. This includes industries like power generation, oil and gas, and aerospace. It provides superior accuracy and consistency compared to traditional torquing methods, ensuring that critical joints maintain their integrity under high stress and pressure.

Do You Need Precise and Uniform Load Distribution?

Hydraulic tensioning can tighten multiple bolts at once, spreading the load evenly across the joint. This is especially useful for large flanges or when gaskets need precise compression to avoid leaks.

Are You Dealing with High-Pressure or High-Temperature Environments?

In tough environments like petrochemical plants or subsea projects, hydraulic bolt tensioning is highly effective. It delivers more reliable results where traditional torque methods might not be enough.

Do You Need to Minimize Galling and Thread Damage?

Hydraulic tensioning lowers the risk of galling and thread damage since it tightens without turning the nut under high pressure. This is especially helpful with costly or specialized fasteners.

Are You Working with Longer Bolts?

Hydraulic tensioning works better for longer bolts or studs. Its axial stretching method provides the right preload more effectively than traditional torquing.

Why Choose Hydraulic Bolt Tensioning?

Accuracy

Hydraulic tensioning offers greater accuracy than torquing by directly measuring bolt load with hydraulic pressure. This removes variables like friction and thread condition, ensuring more reliable and consistent joint strength.

Load Loss and Relaxation

It helps reduce load loss and relaxation by evenly distributing the load across all bolts when tensioned simultaneously. This lowers the risk of uneven settling over time.

Productivity

Tensioning multiple bolts at the same time speeds up installation and reduces the need for re-tightening, saving time and boosting efficiency.

Safety

Hydraulic tensioning is safer than traditional methods, especially for large bolts. It requires less physical effort and lowers the risk of injuries from heavy torque tools.

What Are the Key Factors to Consider When Using Hydraulic Bolt Tensioning?

The ‘when’ and ‘why’ of using hydraulic bolt tensioning is only part of the equation. You also need to consider the ‘how.’ Make sure to keep these factors in mind during bolt tensioning:

  • Proper tool selection – Choosing the right hydraulic tensioner is essential. Consider factors like bolt size, required load, and available space. ALLTORC offers a variety of tensioners for different industries and applications.
  • Calibration – Regular calibration is crucial to maintain tool accuracy. ALLTORC provides calibration services to keep your equipment performing at its best.
  • Correct bolt load – Determining the right bolt load involves considering joint design, operating conditions, and material properties. 
  • Gasket behavior – In gasketed joints, controlling gasket compression is key to preventing leaks. Hydraulic tensioning ensures precise compression without over-compressing, achieving a reliable seal.

How Does Hydraulic Bolt Tensioning Compare to Traditional Torquing Methods?

What Are the Main Differences?

While both methods aim to achieve the desired preload, they take different paths. The main differences include:

  • Focus – Hydraulic tensioning elongates the bolt axially while torquing relies on overcoming friction to rotate the nut.
  • Control – Hydraulic tensioning offers more direct control over the bolt load.
  • Accuracy – Hydraulic tensioning eliminates variables that can affect torque-based tightening, such as friction.

When Might Torquing Still Be Preferred?

Despite the advantages of hydraulic tensioning, there are still situations where torquing might be preferred. These include applications with limited access, where hydraulic tensioners may not fit, or in less critical joints where the higher precision of tensioning isn’t necessary.

Maximize Your Bolt Tensioning Potential

Hydraulic bolt tensioning offers numerous advantages in terms of accuracy, efficiency, and joint integrity. It’s particularly beneficial for critical joints, high-pressure environments, and applications requiring precise load control. However, the decision to use hydraulic tensioning should be based on a careful evaluation of your specific requirements, including joint design, operating conditions, and maintenance needs.

Relieve Tension When Partnering with ALLTORC 

At ALLTORC, we specialize in providing top-of-the-line hydraulic tensioning equipment and services. Our team of experts can help you determine if hydraulic bolt tensioning is the right choice for your application and guide you in selecting the most appropriate tools and procedures. Contact us today.