Compression fittings are essential components in industrial piping systems, providing a reliable, easy-to-install, leak-proof connection between tubing. 

These fittings are widely used across various industries, including oil and gas, pharmaceuticals, water treatment and chemical processing, due to their ease of installation and versatility. 

If you’ve heard about compression fittings, but have never found a reliable source that answers all your relevant questions, you’re in luck. 

This guide provides a comprehensive understanding, answering all your compression fitting questions and more, from how they work and what their major advantages and best practices are, to what makes Ibex Australia’s VIS-LOK compression fittings the perfect choice for your needs. 

How do compression fittings work?

Compression fittings create a reliable, leak-proof connection by mechanically compressing components around the pipe or tubing. There are three main components involved in compression fittings:

1. Nut: This is the threaded component that you use to screw onto the body of the fitting.
2. Ferrules: These are ring-shaped pieces that fit around the pipe. They’re typically made of metals, such as copper, brass or stainless steel, or plastic. Single ferrule fittings usually require one ferrule, whereas twin ferrule fittings (which are the type of ferrule fittings we stock at Ibex) require two. 
3. Body: This is the main component of the fitting that houses the pipe and ferrule(s). It has threads to receive the nut and a connection for the pipe or tubing.

Now that you have an understanding of the pieces involved in compression fittings, here’s a detailed explanation of how they work together at each stage of the installation process:

1. Preparation: The first step of compression fitting involves cleaning the end of the pipe or tube and ensuring the pipe end is smooth. This helps make sure no debris or burrs impact the flow of liquid or gas through the pipe, and that the ends are smooth enough to create a proper seal.
2. Assembly: Once clean and smooth, you can start assembling by sliding the nut onto the pipe or tubing, followed by the ferrule(s). The ferrule(s) are crucial here, as they provide compression and create a seal when the nut is tightened.
3. Tightening: Next, you’ll screw the nut onto the fitting body using a wrench to tighten. As the nut is tightened, it compresses the ferrule(s) against the pipe and the fitting body, creating a secure, leak-proof seal. If you’re using an Ibex Australia VIS-LOK Compression Fitting, you can rely on our red check ring to tell you when your fitting has reached the correct tightness. Once your fitting has reached the correct tightness, the check ring will pop off the fitting, eliminating any over- or under-tightening risks. 

What makes compression fittings reliable and leak-proof?

When properly connected, compression fittings provide a secure and leak-proof connection. What creates this effectiveness is the mechanical compression of the ferrule(s). Here’s how the principles of compression work to ensure your fittings maintain a leak-proof seal:

• Ferrule compression: When you tighten the nut, it pushes the ferrule(s) into a conical seat within the fitting body, causing the ferrule(s) to deform and create a seal.
• Pipe grip: Once the ferrule(s) have deformed, they also grip the pipe tightly, which creates a secure connection by preventing the pipe from moving.
• Seal creation: The tight grip and deformation of the ferrule(s) ensure that there are no gaps between the pipe, ferrule(s) and fitting body. This prevents leaks, making sure your fittings are leak-proof.

What are the main types of compression fittings?

You can obtain compression fittings in a variety of types, each designed for specific applications and requirements, offering you a wide selection to choose from depending on your needs. 

To help you choose the right fitting, and ensure durable, leak-proof connections in your piping systems, here’s an informative overview of the main types of compression fittings:

1. Standard compression fittings 

These are the most common types of compression fittings, and they typically consist of a nut, single ferrule and a fitting body. Because they’re cost-effective and easy to install and remove, standard compression fittings are an excellent choice for general plumbing, water-supply lines and low-pressure applications.

However, if you require a high-pressure or high-temperature application, the standard compression fitting is not ideal. In these situations, more suitable options might include a bite-type compression fitting or double ferrule fitting compressions.

2. Flare fittings

These fittings require the end of the tubing to be flared outward to create a secure connection. The components for this fitting typically include a nut, a flared ferrule and a fitting body with a flared seat. 

Using flare fittings is a great choice if you require a strong and reliable connection for high-pressure applications. For example, professionals who require compression fittings for high-pressure hydraulic applications, refrigeration and fuel lines may find flare fittings the ideal choice.

3. Bite-type fittings

As the name suggests, bite-type fittings have a sharp ferrule that ‘bites’ into the tubing as the nut is tightened, creating a secure seal. The components for this fitting include a nut, a bite ferrule and a fitting body.

If you require a compression fitting for hydraulic and pneumatic systems where high pressure performance is needed, bite-type fittings are an excellent choice, as they provide a strong, leak-proof connection that’s suitable for high-pressure applications.

However, it’s important to note that these fitting types can be more difficult to install than standard compression fittings, and they may not be reusable if the ferrule significantly deforms the tubing.

4. Double, or twin, ferrule compression fittings 

These compression fittings use two ferrules to create a more reliable and secure seal. They consist of a front and a back ferrule, a nut and a fitting body. 

Professionals often opt for a double ferrule compression fitting in high-pressure and high-vibration environments, such as chemical processing and oil and gas industries. 

This is because they provide an extremely strong and reliable connection, and can withstand high-pressure and high-vibration conditions.

Why choose Ibex Australia’s VIS-LOK compression fittings?

With over 30 years of experience delivering high-quality stainless steel piping solutions, Ibex Australia has a comprehensive understanding, backed by extensive data and real-world experience, of what provides customers with the best possible piping solutions.

Our VIS-LOK compression fittings are a remarkable innovation in piping solutions, standing out above the competition due to their unique features, ease of installation and versatile sizing options. 

Here are five unique benefits you can expect from Ibex Australia’s VIS-LOK compression fittings:

1. Supremely reliable, high-quality materials

Our VIS-LOK fittings have been tested in a vacuum, cryogenic and high temperatures, ensuring repeatable and reliable performance in the severest of applications. 

Moreover, our VIS-LOK fittings and seamless tubes provide excellent compatibility, suitable for use with a wide range of tubing materials, including stainless steel, copper and other metal and plastic tubing, offering you superb convenience during your next project.

2. Ease of installation

We designed our VIS-LOK fittings to make your installation process timely and convenient.

In fact, our design features are so innovative and user-friendly that you don’t need to be a professional installer to assemble our fittings. 

For example, our unique design features eliminate over and under-tightening issues, providing you with assurance at every connection that you’re correctly installing your fittings.

We’re so confident in the ease of installation of our VIS-LOK fittings that, should you have any queries or concerns, we have a friendly team of technical experts who can guide and help you at any stage of your project.

3. Innovative design

Our VIS-LOK fittings typically use a double ferrule system, providing a stronger grip and a more reliable seal compared to single ferrule fittings. This double ferrule design ensures a leak-proof connection by evenly distributing the compressive forces around the tubing, reducing the risk of leaks even under high pressure and vibration conditions. 

Our VIS-LOK fittings also feature our flagship red check ring, designed to break free of the fitting once it reaches the correct tightness. This innovative design ensures that over- or under-tightening your fittings are a thing of the past, ensuring you have a leak-proof, reliable system. 

4. Highly versatile

No matter your fitting needs, our versatile range has you covered. Our VIS-LOK fittings come in a variety of configurations, including straight connectors, elbows, tees, crosses and reducers, allowing for flexible design and installation in simple and complex piping systems.

We also provide VIS-LOK fittings in a wide range of sizes to accommodate different tubing diameters and wall thicknesses.

Additionally, our VIS-LOK compression fittings can be easily disassembled and reassembled if needed, making it simple for you to make adjustments and repairs without replacing the entire fitting.

5. Excellent performance under extreme conditions

During the design phase of our VIS-LOK fittings, we used extensive data backed by real-world experiences to ensure our products withstand even the harshest of conditions.

As a result, we’re proud to declare that VIS-LOK’s resilient design can withstand high-pressure applications, making them suitable for hydraulic systems, oil and gas pipelines, and many other demanding environments. 

Additionally, our VIS-LOK fittings operate effectively even in high-temperature conditions, ensuring reliable performance in industrial processes that require heat.

What are the advantages of using compression fittings?

Compression fittings offer numerous advantages, making them a preferred choice for many industrial applications. Some of their main advantages include:

Safer working environment 

There are many potential risks and hazards when using welding and soldering methods to join pipes. For example, you can be exposed to ultraviolet radiation and metal fumes, as well as fire risks from the flames and flying sparks during welding operations. 

Compression fittings don’t require heat, so you eliminate these risks. A simple two-step installation process, without the need for hot work or welding equipment, means you can carry out your pipe fitting work in a significantly safer working environment.

Quick and easy installation

Installing compression fittings is so simple that even hobbyists can find it quick and manageable. 

In fact, there are typically no special tools required; it usually only requires basic tools such as wrenches, meaning you eliminate the need for torches and other heating equipment and technical tools.

Save time and money

Installing, assembling and fixing piping systems with heavy welding and soldering equipment can take a significant amount of time and effort to set up and perform. Because compression fittings are so easy to install, and require so few tools, you can save a remarkable amount of time.

Moreover, due to their installation simplicity, you can install your piping systems yourself, scrapping those high labour costs you might incur from hiring a specialised professional to do the job for you.

What are some challenges with compression fittings?

Despite their numerous benefits, compression fittings can present some challenges. To make your compression fitting experience as smooth and efficient as possible, here are some challenges for you to be aware of:

• Over-tightening or under-tightening: While over-tightening can crush the ferrules, damage the pipe and compromise the seal, under-tightening may fail to compress the ferrule properly and cause connection failures. These issues can lead to leaks and a reduced lifespan.
• Compatibility issues: Ensuring compatibility with different materials and tubing sizes is crucial to avoid performance issues. If you have mismatched sizes between the fitting and the tubing, this can cause leaks and fitting failures.
• Limitations in high-pressure and high-temperature applications: Standard compression fittings may not be suitable for extreme high-pressure and high-temperature environments, such as oil and gas pipelines. This is why, if you require a compression fitting for a demanding environment, it’s important to select one that includes a double ferrule design and is made from high-strength materials.
• Maintenance and inspections: Having a professional inspect and maintain your compression fittings is necessary to ensure continued performance and safety. If you neglect proper maintenance, you may experience challenges like undetected leaks and performance failures.

How do Ibex Australia’s VIS-LOK compression fittings eliminate these challenges?

By choosing Ibex Australia’s high-quality VIS-LOK compression fittings, you have the best chance at eliminating these challenges. 

For example, our VIS-LOK fittings ensure compatibility with a wide-range of applications, and our innovative design eliminates over- and under-tightening issues. These alone remove a lot of common user challenges.

Additionally, because we design our VIS-LOK fittings with durable, high-quality materials and a double ferrule design, you’ll receive reliable pipe fitting solutions that significantly reduce any risk of leaks, eliminating underperformance challenges.

That’s not all, though. At Ibex Australia, we get that for some of our customers, compression fitting may be an entirely new endeavour. That’s why we provide our customers with training support and resources, helping you learn the best installation practices and giving you the peace of mind that your fittings are assembled correctly. 

Our friendly team of expert technicians are also here to guide you through your selection process, ensuring you choose the most suitable materials for your project. 

How do various industries benefit from using Ibex Australia’s VIS-LOK compression fittings?

At Ibex Australia, we pride ourselves on providing versatile, high-performance solutions to an array of industries. Here are some major industries who choose us for our robust VIS-LOK design and our adherence to industry-specific standards:

1. Oil and gas

Both offshore and onshore facilities in the oil and gas industry have found significant benefits from using our reliable VIS-LOK compression fittings.

The reason for this is that, because our VIS-LOK systems are designed to withstand high-pressure systems, they provide excellent fitting options for oil and gas pipelines and process equipment where high pressure is a constant factor. 

Additionally, our VIS-LOK’s corrosion-resistant materials and double ferrule design guarantee a leak-proof connection, making them highly suitable for the safety demands and environmental regulations of the oil and gas industry.

2. Pharmaceuticals

The materials and design of Ibex Australia’s VIS-LOK compression fittings ensure contamination-free connections that comply with industry standards for cleanability. 

Because of this, the pharmaceutical industry greatly benefits from using our VIS-LOK compression fittings for systems that require strict hygiene and contamination control. 

With VIS-LOK being so simple to install and maintain, the pharmaceutical industry has assurance that their systems integrity is maintained, saving them money and time.

3. Water treatment

The water treatment industry typically uses VIS-LOK compression fittings for filtration systems and chemical dosing systems.

For example, VIS-LOK can be used in water filtration and purification systems for their ability to provide a secure connection in high-flow conditions. They can also provide accurate and leak-free chemical delivery, making them highly suitable for chemical dosing systems that introduce chemicals into water treatment processes.

4. Food and beverage

In the food and beverage industry, hygiene and food safety are paramount. 

While our VIS-LOK systems can’t be used to transport actual food and/or beverages, they can be used in this industry to move all supplementary services required, such as potable water, waste, oil, compressed air etc.

5. Chemical processing

The design of our VIS-LOK compression fittings is made from materials that resist corrosion from a variety of chemicals. 

For this reason, the chemical processing industry benefits from VIS-LOK’s ability to handle reactive and corrosive chemicals, ensuring safe and secure connections that prevent hazardous spills and leaks.

What are the technical specifications and standards of VIS-LOK compression fittings?

Ibex Australia’s VIS-LOK compression fittings meet and exceed industry standards, providing quality assurance and outstanding performance. Here’s an overview of our key specifications:

Material composition

VIS-LOK compression fittings are crafted from high-quality materials to provide our customers with durability, corrosion resistance and compatibility with a wide-range of applications. The primary materials used include:

• Stainless steel (316/316L): with excellent corrosion resistance, high strength and durability, our stainless steel fittings are ideal for applications in harsh environments, such as chemical processing, oil and gas and water treatment.
• Brass: Great corrosion resistance, ease of machining and cost effective, brass fittings are most suitable for general plumbing, water treatment and low-pressure applications.
• Carbon steel: Highly strong and durable, carbon steel is ideal for high-pressure applications where corrosion resistance is not a primary concern.

Pressure ratings

VIS-LOK fittings do not have a pressure rating. The pressure rating of your system will be based on the pressure rating of the tube you use. Tube pressure rating will vary based on the wall thickness of the tube used. 

Industry certifications

We have designed our VIS-LOK compression fittings to meet stringent industry standards and certifications, ensuring they’re suitable for a variety of applications. Key certifications include:

• ISO 9001:2015: This is a quality management system certification that demonstrates a commitment to consistent quality and customer satisfaction.
• ASME B31.3: This refers to the American Society of Mechanical Engineers standard for process piping. It ensures VIS-LOK fittings are suitable for use in process industries, including chemical and petrochemical plants. 
• ASTM Standards: This is the American Society for Testing and Materials standards, which includes the ATSM A182 for stainless steel and the ATSM B16 for brass. By meeting this industry standard, we ensure our materials meet quality and performance standards.
• NACE MR0175/ISO 15156: This is the industry standard for materials used in hydrogen sulphide-containing environments in oil and gas. It ensures our VIS-LOK compression fittings are capable of resisting sulphide-induced stress cracks, a crucial requirement for oil and gas applications.
• CRN (Canadian Registration Number): This is required for all pressure fittings used in Canada, ensuring compliance with Canadian pressure vessel and piping regulations.
• PED (Pressure Equipment Directive): This is the European Union directive for the design and manufacture of pressure equipment, ensuring VIS-LOK fittings meet EU safety standards.

What are the best practices for VIS-LOK installation?

Learning about the best practices for VIS-LOK installation can help you ensure the long-term performance and reliability of your VIS-LOK compression fittings. Here are some helpful best practices for you to consider when assembling your fittings:

• Prepare properly: To ensure you’ve properly prepared and are ready for installation, it’s a good idea to check all the components (fittings, tubing and tools) are clean and free from any debris, oil and contaminants. Take some time also to inspect for any visible damage or defects in the fittings and tubings. 
• Cut the tube using the right tools: The safest and most effective way to cut your tube is to use a tube cutter or a fine-toothed hacksaw, as this ensures clean, square cuts. After this, remove any burrs from the tube ends using a deburring tool to ensure a smooth surface that’s ready for sealing.
• Assemble your fittings in the correct order: For a correct installation, start by placing the nut and then the ferrule(s) onto the tubing. From here, insert the tubing into the fitting body until it bottoms out. Then hand tighten the nut onto the fighting body until it’s finger-tight.
• Tighten using the correct tools: Use two wrenches for tightening – one to hold the fitting body and the other to tighten the nut until the red check ring breaks free from the fitting, indicating the fitting has reached the correct tightness. Doing this ensures the ferrules are properly compressed for a leak-proof seal, without the shadow of a doubt. (If you have someone nearby, ask them to help you by holding the fitting body in place with one wrench while you tighten the nut with the other, as this will make the process much easier.)
• Perform a thorough inspection: To make sure you’ve properly assembled your fittings, spend some time at the end visually inspecting them, paying close attention to their alignment and tightness. You can also perform a pressure test to verify the integrity of the connection before putting the system into service.

What are the best practices for VIS-LOK maintenance?

Once you’ve installed your VIS-LOK fittings, it’s important to maintain them to ensure they remain reliable and secure. Here are some maintenance best practices for you to follow:

• Conduct regular inspections: Schedule some time, roughly every six months, to check your fittings for signs of wear, corrosion or leaks.
• Perform periodic tightening checks: Following your manufacturer’s guidelines, check and re-tighten your fittings as needed. A torque wrench is the ideal tool for performing tightening checks.
• Replace worn components: To prevent leaks or system failures, it’s important you replace any worn or damaged components immediately. You can organise yourself effectively for these situations by keeping an inventory of spare parts, such as nuts, ferrules and fittings. 

VIS-LOK Case study examples

IBEX Australia’s VIS-LOK compression fittings have had major success in providing meaningful solutions to a range of applications across industries. To demonstrate VIS-LOK’s effectiveness, here are several case studies showcasing successful implementations:

Fluid Power Services

Since 1991, Fluid Power Services (FPS) has remained a leader in the fluid power industry. Recently, the company started work on a new project for a High-Pressure Lubrication Oil Sprayer.

This project was critical, demanding an expedited installation timeframe, meaning FPS had to look for unique techniques to fasttrack installation.

FPS partnered with IBEX Australia to utilise our innovative VIS-LOK compression system, which provided a significant reduction in installation time over traditional techniques like flaring and welding. 

Brendan Fielding, Business Development Manager with FPS, has personally worked alongside IBEX Australia for over 10 years, and highly recommended our VIS-LOK compression fittings and Tubepress press fit as the best solutions for this project for increased quality and a significant reduction in installation time.

Australian Fluid Handling

Australian Fluid Handling (AFH) has become a major national supplier of Engineered Skid packaged equipment since the company was founded in 1999.

AFH provides bespoke engineered solutions for oil and gas, industrial processing and fuel management. 

The company’s project engineering team partnered with IBEX Australia to use our VIS-LOK instrumentation compression fitting solutions. 

In partnering with AFH, we supplied them with VIS-LOK twin ferrule tube compression fittings and provided customised expertise, resulting in outstanding outcomes for the company’s projects.

For dozens of more real-world examples of IBEX Australia’s successful compression fitting implementation, visit the Ibex Australia website.

Explore Ibex Australia’s range of compression fittings

Compression fittings, especially Ibex Australia’s VIS-LOK system, provide reliable, efficient and versatile solutions for a large range of industrial piping needs. 

By understanding their functions, advantages and best practices for installation and maintenance, you can ensure optimal performance and longevity for all your fittings. 

Explore Ibex’s range of compression fittings and contact our technical support team for personalised advice tailored to your specific requirements.