DIN 3861

This standard applies to non-soldering compression fittings. It also specifies the types of compression rings to be used.

ASTM F1987-01 (2006)

This standard is a requirement for compression fittings with a multilayer pipe type 2 used for hydronic heating systems.

SAE J246

It covers dimensional specifications for flanged sleeve compression types and tube fittings for air brake systems.

NSF

NSF standards are greatly tied for lead-free products.

A brass compression fitting can be used with brass, plastic, copper, and aluminum tubing.

Note: it is not recommended for steel tubing.

For you to decide on what should you choose between the two, we need to consider the ease of installation, quality, and cost.

Thus, we have listed the advantages and disadvantages of these two fittings.

Advantages of a Brass Compression Fittings

• Brass is a strong fitting. It has excellent strength and is very reliable for PEX fittings.
• Installation procedure. Brass compression fittings are very easy and quick to install. It can be done properly in just a few minutes.

Disadvantages of a Brass compression Fittings

• If not properly used, a brass compression fitting can affect a pipe’s performance. If used with acidic water, the pipe will more likely to burst. For some, brass compression fittings do not have a good performance.
• Brass compression fittings are costly than plastics.

Advantages of Plastic Compression Fittings

• Plastic compression fittings are reusable and re-mountable. It can be removed easily, cleaned, and maintained. It also doesn’t break easily.
• It is a better choice for acidic water applications because it does not corrode.
• Plastic compression fittings are also less likely to leak.

Disadvantages of a Plastic Compression Fitting

• A plastic compression fitting has a tougher installation process than brass compression fittings. Installing a plastic compression fitting requires a rigorous procedure.
• Plastic fittings are also considered less durable, have a small diameter, and are less effective.

Now that you know the advantages and disadvantages of these two fittings, you can make a decision on what should you use for your applications.

Many brass compression fittings can be used on a plastic pipe, but not all.

If you use a brass compression fitting on a plastic pipe, it shouldn’t exceed 2 full turns after the ferrule gripped the pipe.

Using a brass compression fitting on a PEX is not usually recommended.

It is not usually used for 3/8″ CTS or 1/2″ OD or other larger pipes.

Instead of using a brass compression fitting, you can use brass or plastic push fittings and brass poly fittings for PEX applications.

Yes, only if they are compatible with each other. You should not use a brass compression fitting with a short tube in a speed fit.

If you use a brass compression fitting on stainless steel tubing, you will less likely to achieve proper sealing.

It is because brass is not hard enough for the ferrule to bite into the stainless steel tube.

Mostly, 90% of a compression ring or sleeve will not slide in a bent tubing.

Excellent Corrosion Resistance

Its material composition makes it more resistant to corrosion making it suitable for industrial fluid application.

Higher Tensile Strength

Brass is a copper alloy made with Zinc. Thus, it can provide excellent hardness and additional strength. Thus, it is more resistant to high pressure.

Durable

A brass compression fittings are durable and can provide longer service life if installed, cleaned, and maintained properly.

It is easy to know and understand how much pressure a brass compression fitting can hold. It typically depends on the application.

You can find its maximum pressure rating or nominal working temperature in the front or back packaging or by contacting its manufacturer.

A brass compression fitting encompasses broad uses and applications. Because of its excellent sealing capabilities, these are widely used for:

• Industrial usage
• Hydraulic applications
• Subsea applications
• Plumbing systems
• Oil and gas applications
• Pneumatic application
• Water Systems

Brass materials are more likely to have lead content. It is not usually used in the food industry, drinking water, or beverage industry in the past.

However, in the advent of non-leaded brass, it is possible to use brass compression fittings in a potable water application with some considerations.

A brass compression fitting must be ANSI certified (requires a brass to contain only a 0.25% lead-weighted average).

If your brass compression fittings are certified by ANSI and other standards for lead-free brass, they can be used in potable water and can easily replace old standard brass fittings.

A brass compression fitting is composed of three elements – the compression fitting body, compression nut, and a ferrule.

Compression Fitting Body

It is the main part of the brass compression fitting. It is made to resist corrosion while providing a longer service life.

Compression Nut

When the compression nut is tightened, it tightly compresses the brass sleeve. Thus, making a watertight seal.

Ferrules

Ferrules are also known as compression rings or olive. It functions as the compression fitting assembly’s main sealing component.

Ferrules made from metals provide stability in a wide temperature range application. It can withstand compression loads with no relaxation.

i. Ferrule shape

The mating angle and ferrule shape are one of the major considerations for a reliable compression seal. These two components must be tapered so when the nut is tightened it can be compressed properly.

Most importantly, you should take into consideration that your ferrule has a sharp forward edge.

ii. One-piece vs. Two-piece Ferrules

A basic compression fitting has only a single ferrule. This design reduces the overall number of components. It offers reliable work for brass and other soft materials.

However, for some hard materials, as the nut is tightened, the torque can be transferred from the compression nut to the ferrule that will lead to asymmetrical compression.

Thus, adding another ferrule helps in decoupling the nut while preventing the torque transfer.

iii. Asymmetrical vs. Symmetrical Ferrules

Asymmetrical ferrule typically has a cone shape. It can only be positioned in one direction of the fitting.

Meanwhile, symmetrical ferrules have a cone shape on both ends. It can be positioned in either direction in the fitting.

The most common material used is brass. When purchasing a brass compression fitting, you must take precautions and always choose a lead-free one.

•         CA360 Brass for bar stock fittings.
•         CA377 Brass for forged fittings.

A brass compression fitting is considered more reliable than threaded fittings. However, a brass compression fitting has a low resistance to vibration. Repeated bending of the brass compression fittings can lead to the loss of the ferrule’s grip on the tube.

A brass compression fitting works by compressing the ferrule between the pipe and the tapered surface such as connector, valve, or another type.

The nut is tightened using a grip or a spanner to exert pressure make the ferrule bite the pipe.

A brass compression fitting can work properly if the pipe is cut and cleaned thoroughly.

Teflon tape usually refers to any tape labeled with PTFE or PolyTetraFluoroEthylene. It is also commonly referred to as a plumber’s tape.

Teflon comes with a wide range of thicknesses, widths, and colors.

If your brass fittings do not have a rubber gasket already, you can use Teflon tape. A Teflon tape can help in making effortless and smooth watertight seals.

When applying a Teflon tape, make sure you put it in the male thread direction for a secured result.

A brass compression fitting is reusable in a range of applications like power plants, plumbing, and electrical.

They are often preferred and recommended due to their soft and durable performance.

The three components of the brass compression fittings (compression fitting body, compression nut, and ferrule) are safe to be reused.

However, these materials must be checked before reusing and assembly to ensure that they are still in good connection. Thus, making sure that they will not pose any threat during the assembly process.

Please note that if the connection is not properly installed, leaks can be possible.

In order to decide whether a brass compression fitting is as good as a soldered fitting, we have listed the advantages and disadvantages of this fitting.

Advantages of A Brass Compression Fitting:

• A brass compression fitting is more popular in most industries nowadays since it does not require a solder or flare during assembly.
• Brass compression fittings are also easy to quick to use. You do not need any special skills or special tools to operate. You can do the task by yourself.
• Brass compression fittings are useful in a situation where a soldering torch or any heat source is banned.
• A brass compression fitting is also useful when joining tubes with dissimilar materials. For partial removal or occasional disassembly, a brass compression fitting is an ideal use.

Disadvantages

• Brass compression fittings are bulky since it requires different parts to create a seal.
• It is less aesthetically pleasing than soldered fittings.
• Brass compression fittings are less robust than soldered fittings making them susceptible to powerful stress.
• A brass compression fitting has a low tolerance for flexing or bending making it a poor choice for the application that requires lots of bending. It is also not a good choice for applications with excessive tube movement and vibration.

More people opt to over tighten their fittings to ensure a secure connection instead of failing.

However, a common issue that arises due to misconceptions is actually coming from overtightening rather than under-tightening.

So, how can you tell if you over-tightened your connections? Here are some manifestations.

1. Tubing and Fittings are Deformed

Tubing and fittings are deformed if you did not follow the proper tightening procedure. You are most likely to encounter problems if these are deformed during the installation.

If you overtighten the fittings, lots of force and pressure are exerted resulting in shape warping and additional damages.

2. The Valve or Fitting Body Breaks

Fitting bodies or valves are specially made to ensure sturdiness making it break-resistance. However, if it is broken, you have exerted too much pressure on it. In short, overtightening makes your valve break.

3. You Can’t Get the Fitting Off

Obviously, everyone wants a secured tubing connection. However, if it is overly secured, it is possible that you have overtightened it resulting to tube damage.

4. Leaks are Starting Off

If the connection starts leaking off, you may consider checking it and see it is overly tightened. If the connection is overtightened, it can lead to deformation. Deformation can also lead to gaps and cracks where leaks can start off.

Overtightening of your compression fittings can provide a direct impact on your applications. These are the common effects of overtightening:

• Increased system leakage
• Increased safety risk and concerns
• Damaged due to overtightening will incur a higher cost for replacement
•  Area and equipment damage such as a wall, tube, or floor due to leakage
•  Leaking tubes can create pollution and other environmental concerns
•  Damaging of valves and tube fittings
•  Broken valves and tube fittings
•  Inaccurate tube fitting connection
•  If your fittings are exposed to maximum tightness level it can aggravate its natural wear process

Yes, a brass compression fitting can be used behind walls specifically in a bathroom since bathroom fixtures are not subjected to excessive movement and vibration.

It can be used for cold and hot water feed lines.

Note: Although you can install a brass compression fitting for a low-pressure behind walls application, you may consider potential problems that will incur. Brass compression fittings can lose over time and can cause leaks behind the walls. If you opt to choose a brass compression fitting behind walls, make sure that it is accessible enough for maintenance and repair.

There are two types of brass compression fittings – Type A or non-manipulative fitting and Type B or manipulative fitting.

Type A or non-manipulative Fitting

This type of brass compression fitting is easy to install. You can install it without any tubing modifications.

You can also assemble these fittings by only using a wrench for tightening the nut.

It is typically used for water connections.

Type B or Manipulative Fitting

When you install a Type B fitting, it requires belling or flaring the tubing.

You may need a special pulling tool for siding the olive and nut away from the tube.

These are commonly used for gas lines.

Mixing and matching a brass compression fitting component is not usually recommended.

Although two different components from different manufacturers look the same, they mostly vary in key internal dimensions such as thread size, pitch, ferrule length, and body/taper.

Mixing and matching brass compression fitting components from different manufacturers can create a variable result.

Before purchasing a brass compression fitting, consider first the size of the pipe or tubing.

Choosing the right size is essential for creating a well-sealed and exact seal.

Here are the size options you can choose:

• 1/8”
• 3/16”
•  1/4”
•  5/16”
•  3/8”
•   7/16”
•   ½”
• 5/8”
• ¾”
• 7/8”

A brass compression fitting is not likely to leak unless it has a strain or is not installed properly.

If you notice that your fitting is leaking, find out first where the leak is coming from.

Then, turn the water off. It is the best way to stop the leak, avoid get splashed, and save water costs.

After turning off, inspect for any malfunction, take the fitting apart, and reassemble it.

If the leak doesn’t stop after reassembling, you need to replace the fitting and the tubing connected to it.

A brass compression fitting is very common. Their threads don’t match with other thread types.

A brass compression fitting has a straight thread made from brass materials. It is often used for small-diameter tubing or soft copper pipe.

One typical example of a brass compression fitting is the angle stop under a sink.