How Do You Use Flare Fittings?

Do flare fittings need sealant?

Thread sealant must be used when the threads themselves make the seal, as in normal pipe threads. But if the function of the threads is simply to hold two sealing surfaces together, then the threads should not be sealed.

How does a flare fitting 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.

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.

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.

Do you use Teflon tape on a flare fitting?

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. tighten more if a leak is detected.

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 are flare type fittings?

Flare fittings
A flare fitting has a tapered end that fits into a flared piece of tubing and is secured in place with a sleeve and flare fitting (threaded nut) to produce a pressure-resistant, leak-tight seal.

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.

Can flare fittings be reused?

Flare fittings are reusable until cross threaded. If they were already crossed toss them. If not be careful re assembling them and you will be fine.

Why is a flare connection 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.

Do propane fittings need Teflon tape?

When connecting gas pipelines and their fittings to a stove, grill or other connection, it is important to use Teflon tape designed for gas connections and not Teflon tape designed for water pipes. Teflon tape seals the gas fittings’ threads and keeps leaks from developing.

How tight should propane fittings be?

In general terms you want to aim for 2 to 3 full turns after hand tight. If it still feels loose, complete another full turn. A lot of plumbers will use both teflon tape and pipe dope. Depending on the thickness of the teflon tape you will want to use 3 to 6 wraps in the direction on the threads.

Can you use flare fittings for water?

While it’s legal to use flare connections on water lines, it’s rarely done. A leaking water line won’t fuel a fire or lead to an explosion, and residential water pressures aren’t high enough to warrant the use of this robust but relatively labor-intensive joint.

What is a flare nut used for?

Obviously, flare-nut wrenches are best for tightening or loosening hexagonal nuts and fittings. This makes them versatile and useful, especially for working on cars or plumbing. The most popular industry to use flare-nut wrenches is the automobile industry.

How do you size an fitting?

AN sizes range from -2 (dash two) to -32 in irregular steps, with each step equating to the OD (outside diameter) of the tubing in 1/16″ increments. Therefore, a -8 AN size would be equal to 1/2″ OD tube (8 × 1/16 = 1/2).

Can you use an fittings for AC?

There are braided-type hoses and fittings made for AC use, but the usual stuff you use for oil hoses, etc. will not work. Refrigerant molecules (especially R-134a) will seep right through most rubber hoses and the AN flare fittings as well.

What O-rings are best for hydraulics?

EPDM O-rings have excellent resistance to heat, water, steam, ozone and sunlight. EPDM O-rings are particularly useful when sealing phosphate-ester hydraulic fluids and may be appropriate for some applications in place of NBR.