When soft copper tubing is used for plumbing, different styles of compression fittings are used to make make leak-proof connections. To make sure that the fitting will be leak-tight, you have to flare copper tubing properly using the proper tools and techniques.

What is the purpose of flaring a copper tube?

Flaring tools use pressure to make a fabricated mechanical joint for joining or sealing copper tubing with a flare connection. Flaring allows you to connect tubes to each other or another kind of fitting.

Should you anneal copper before flaring?

When flaring Types L or K copper tube, annealed or soft temper tube should be used. It is possible to flare Types K, L or M rigid or hard temper tube, though prior to flaring it is usually necessary to anneal the end of the tube to be flared.

Why do we flare tubing?

During assembly, a flare nut is used to secure the flared tubing’s tapered end to the also tapered fitting, producing a pressure-resistant, leak-tight seal. Flared connections offer a high degree of long-term reliability and for this reason are often used in mission-critical and inaccessible locations.

What is Flare piping?

A Flare system is a means of safe disposal of waste gases by burning them under controlled conditions. Flare piping generally comprises of PSVs outlet piping, subheader piping & main header piping.

Why are flare fittings used?

Flared fittings are also a good option for use with heavy machinery, and industrial and construction equipment. They are the fitting is most commonly used to connect tube or hose in high-pressure and high-temperature applications. The flare fitting is commonly used world-wide because it is a simple construction.

Do you use Teflon tape on flare fittings?

Do not use Teflon ® tape or pipe sealant on any flare ends because you will not obtain a leak-free seal. Keep flare end of fitting free of grease, oil and thread sealant. Use a wrench only on the hex surfaces of the fittings.

How do flare fittings seal?

Design: The 37° flare AN seal is used for sealing tubing to end connections. It requires the end of the tube to have a nut slipped onto it and then flared out using a special tool. To seal properly, the nut is threaded into a flare fitting which clamps the flared tube in between the nut and flare fitting.

Why is a flare connection preferred to a solder connection?

What actually seals the connection in a flare connection? Why is a flare connection sometimes preferred to a solder connection? … The primary advantage of flare connections is that they form a relatively large contact area, making a reliable seal that’s resistant to damage from vibration.

What is the angle on a flare connection?

Fitting Flare Angle AN Aircraft Flare fittings have a 37 degree flare angle. Many industrial fittings use a 45 degree flare angle. Most of the time, when you are working on aircraft, the hoses have a 37 degree flare and you don’t think about the flare angle.

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How tight should flare fittings be?

Generally, the tubing should stick up about 1⁄16 in. … This ensures that the block grasps the tubing tightly. After tightening the screws, spin the mandrel into the tubing, tighten it by hand, and check how the flare mates with the fitting.

What is the difference between flaring and swaging?

Both processes have a lot of similarities. The big difference is that flaring is shallower and a different shape. It creates a funnel at the end of the tube. Swaging on the other hand is deeper and you can expand the diameter further along the tube to create a flute shape.

Can you over tighten a flare fitting?

Fourth, don’t over-tighten the flare fitting, as this can cause leaks. Daikin offers preset flare torque wrenches that will allow you to properly tighten the flare fitting without over-tightening them. Always use a backup wrench when tightening any flare fitting.

Why do flare fittings leak?

Bad flare, burrs on the pipe, wrong size flare, can all cause a flare fitting to leak. The most common reason they leak is because of us overtightening them. I once had a tech tighten one to the point that it blow off during pressure testing.

What is the difference between flare and compression fittings?

Generally speaking, compression outlets are used for water and compressed air lines, where slight leakage isn’t going to cause too much of a problem. Flared outlets are used for gas and high-pressure lines, where even a little leakage can cause major problems if left unattended.

What is the difference between NPT and flare?

NPT or IPT pipe threads are tapered, Compression Fitting Threads are Parallel. … On the other hand compression fittings and flare fittings use threads that are cut in parallel, without taper.

Can you reuse flare fittings?

DO NOT reuse connectors, fittings and valves; they are designed for use on original installation only. Removal of connector and additional handling may damage connector making it unsafe for reuse. Overall this is to help prevent leaks caused by dirt, debris, and damage that may prevent good connections.

How do you stop a flare fitting from leaking?

A leak will occur where the cone enters the flare. Loosen and tighten the flare nut several times to the torque specifications. This action will positively seat the cone into the flare. If the joint still leaks, dissemble the connection and wipe off the flare and the cone with a rag.

Is SAE same as flare fitting?

JIC fittings are dimensionally identical to AN (Army-Navy) fittings, but are produced to less exacting tolerances and are generally less costly. SAE 45-degree flare fittings are similar in appearance, but are not interchangeable, though dash sizes 2, 3, 4, 5, 8, 10, 14, and 16 share the same thread size.

Is a flare fitting the same as an?

AN and JIC Fittings Interchangeability AN 37° flare and industrial 37° flare fittings function identically. In many cases, they appear to be functionally interchangeable, but they are not.

Are all flare fittings the same?

AN 37° flare and industrial 37° flare fittings function identically. In many cases they appear to be functionally interchangeable, but they are not. What this means is that while the products may look similar, you must not use an industrial 37° flare fitting design as a direct substitution.