How to Use a Tube Flaring Tool Correctly: Step-by-Step Guide for HVAC Copper Tubing

Introduction

A properly made flare connection is one of the most important factors in the reliability of an HVAC or refrigeration system. Even a high-quality flare fitting may leak if the flare itself is uneven, cracked, or incorrectly formed.

Fortunately, creating a professional flare is not complicated when the correct tools and procedures are used. This guide explains the complete flaring process, helping technicians and tool buyers understand how a tube flaring tool works in practical HVAC applications.

If you're new to flare connections, you may first want to read our guide:

What Is a Tube Flaring Tool?

H2 Tools Required Before Flaring

Before starting, prepare the following tools:

• Tube flaring tool kit

• Copper tubing cutter

• Deburring tool

• Tube bender (if required)

• Flare nut

• Soft copper tubing

Using dedicated HVAC tools improves both installation quality and efficiency.

→Related Products

• Tube Flaring Tool Kits

• Copper Tubing Cutters

H2 Step 1 – Cut the Copper Tube Properly

Always use a professional tube cutter instead of a hacksaw.

A clean, square cut helps the flaring cone apply even pressure around the tube end.

An uneven cut often leads to:

• Off-center flares

• Thin flare edges

• Poor sealing performance

H2 Step 2 – Remove Burrs

After cutting, inspect both the inside and outside of the tubing.

Small burrs left inside the pipe can damage the flare during forming.

Use a deburring tool to remove sharp edges and create a smooth tube opening.

→Related Product

Copper Tubing Cutters

H2 Step 3 – Install the Flare Nut

Before inserting the tubing into the flaring bar, slide the flare nut onto the pipe.

Although simple, this is one of the most common mistakes made during field installation.

If forgotten, the flare must be cut off and repeated.

H2 Step 4 – Secure the Tube in the Flaring Bar

Insert the copper tube into the matching hole of the flaring bar.

The tube should extend slightly above the bar surface according to the manufacturer's recommendation.

Proper clamping prevents the tube from slipping while forming the flare.

H2 Step 5 – Position the Flaring Cone

Place the yoke over the flaring bar and align the cone directly with the center of the tube.

Apply pressure gradually.

Avoid sudden force.

Modern eccentric flaring tools use a rolling action that produces smoother flare surfaces than traditional cone designs.

H2 Step 6 – Form the Flare

Rotate the handle steadily until the cone fully forms the flare.

There is no need to apply excessive force.

Over-tightening may:

• Crack the flare

• Thin the copper wall

• Reduce sealing performance

The finished flare should have a smooth and even surface with a consistent 45° angle.

H2 Step 7 – Inspect the Finished Flare

Before assembling the fitting, inspect the flare carefully.

A good flare should be:

✔ Smooth

✔ Even

✔ Centered

✔ Free of cracks

✔ Uniform thickness

If defects are found, cut off the damaged section and repeat the process.

H2 Common Mistakes When Using a Tube Flaring Tool

Even experienced technicians occasionally make mistakes.

Tube Slips During Flaring

Cause:

Insufficient clamping force.

Solution:

Tighten the flaring bar evenly before forming.

Flare Cracks

Cause:

Hard copper tubing or excessive pressure.

Solution:

Use annealed copper tubing whenever possible.

Uneven Flare

Cause:

Tube not positioned correctly.

Solution:

Ensure the tubing extends evenly from the flaring bar.

For a complete troubleshooting guide, see:

Common Tube Flaring Problems and How to Fix Them

H2 Why Proper Flaring Matters

A high-quality flare connection provides several advantages:

• Better refrigerant sealing

• Longer system service life

• Easier maintenance

• Reduced installation failures

Professional installers understand that a few extra minutes spent preparing the tubing can prevent expensive service calls later.

H2 Related HVAC Installation Tools

Tube flaring is only one step of copper tube installation.

Other commonly used tools include:

Copper Tubing Cutter

Used before flaring.

（产品内链）

Pipe & Tube Bender

Used after flaring when routing tubing around equipment.

Together, these tools help achieve professional installation quality.

H2 Conclusion

Using a tube flaring tool correctly is essential for creating reliable copper tube connections in HVAC and refrigeration systems.

By following proper cutting, deburring, positioning, and inspection procedures, technicians can significantly reduce leakage and improve installation quality.

Whether working in the field or selecting tools for distribution, understanding the correct flaring process is the foundation of successful copper tube installation.

FAQ

How far should copper tubing extend above the flaring bar?

Most manufacturers recommend a slight extension, depending on the tubing size and tool design.

Why is my flare cracking?

Cracks usually result from work-hardened copper tubing, excessive forming pressure, or poor tube preparation.

Should lubricant be used during flaring?

Some technicians apply a small amount of refrigeration oil to the cone to reduce friction and improve surface finish.

Can the same flaring tool be used for aluminum tubing?

Yes. Most professional flaring tools are suitable for both soft copper and aluminum tubing.

Related Articles（Topic Cluster）

• What Is a Tube Flaring Tool?

• How to Flare Copper Tubing Without Leaks

• Common Tube Flaring Problems and How to Fix Them

• 45° vs 37° Flaring Tool: What's the Difference? 

Related Quality Control Guide for Importers

Before approving a bulk order, use our HVAC Flaring Tool Kit Quality Inspection Checklist to verify specifications, workmanship, flare performance, OEM branding, packaging and inspection records.

About TORCHMARK

TORCHMARK (Ningbo Torchmark Hardware Co., Ltd.) manufactures HVAC flaring tools, tube benders, drain augers and rivet nut guns in Ningbo, China, supplying global distributors as OEM/ODM and private label. Related reading: Wholesale OEM Tube Flaring Tool Kits, Drain Auger Cable Diameter Guide, How to Use a Tube Flaring Tool, Manual Drain Auger Manufacturer.