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How to bend copper bars and copper pipes

Copper bars can be bent with virtually every bending process.

While copper is soft, it’s not soft enough to bend smoothly and perfectly on its own. Bending copper pipes without special methods or tools usually results in pipe collapse. Instead of a continuous curve, the pipe will crimp and fold at the intended bend point. For crafting, it’s generally not the look you want. For plumbing, it impedes water flow.

3 ways to bend the copper bar

There are 3 ways to bend the copper bar to fabricate your products.

  1. Large-radius bent copper bar is rolled on a section bending machine(also known as a profile bending machine or angle roller).
  2. Curved copper bar requiring tight radii is rolled on a rotary-draw bending machine through a technique called mandrel bending.
  3. Helical spiral bending can be performed on any copper bar section using a CNC 4 roll bending machine.
bending copper bar

For very tight radius bending you can utilize a stretch forming process where you must stretch the material (draw the material) around a bend die matching the desired bend radius.

But for larger or sweeping radii must utilize a roll bending process (section bending). At this time, need to use a flat copper bar bending machine.

Flat copper bars are solid, which means that they can be easily bent into the shapes required by a project. There are two ways to bend non-circular or non-square copper bars:

bending copper bar
bending copper bar

The easy-way and hard-way to bend copper flat bars

bend flat bar
bending flat bar

Easy Way

The Easy Way: This involves bending a bar along the wider axis of the bar. This means an easier bend, reducing the problem of rippling on the inside of the curve. Bars bent the easy way resemble a belt when completed.

Hard Way

The Hard Way: Bars bent in this manner are bent along the thicker axis. This also presents more difficulty during the bending process, as rippling and compression can occur on the inside of the bends. When bent the hard way, bars resemble a metal washer.

Two Types of Copper Bar Bending Machines

How to bend the copper pipe and tubing without getting kinks/ripples

Because of its exceptional formability, copper can be formed as desired at the job site. The copper tube, properly bent, will not collapse on the outside of the bend and will not buckle on the inside of the bend. Tests demonstrate that the bursting strength of a bent copper tube can actually be greater than it was before bending.

There are a number of reliable ways to bend copper pipe. Because copper is readily formed, expansion loops and other bends necessary in an assembly are quickly and simply made if the proper method and equipment are used. Simple hand tools employing mandrels dies, forms and fillers, or power-operated bending machines can be used. A few of the methods don’t even require special tools.

3 Tips For Bending Copper Pipe

  • Pipe Support: Supporting the copper pipe along the entire length of its bend is key to a consistent shape. Support can either be inside or outside of the pipe.
  • Bend Slowly: Bending the copper pipe quickly might still crimp it, even if it is properly supported. Or, if you do manage to get the right curve, ripples may develop on the inside of the curve. Always bend slowly.
  • Shape the Bend: Bending the pipe over a padded knee is the quickest way to bend copper pipe to an approximate 4- to the 8-inch radius. But you can also use other curved shaping items: metal cans, buckets, or large pipes.

Top 6 methods for bending the copper pipes

Helical Coil Bending and Spiral Bending 【how to bend copper pipe】

Bending copper pipe requires careful technique to avoid kinks or deformations. Here are six common methods, along with some general tips, for bending copper pipe effectively:

Using a 3-Roll Profile Bending Machine

A 3-roll profile bending machine, also known as a section bending machine or an angle roller, is a specialized tool designed to bend metal tubes and pipes with precision. This method is suitable for creating consistent bends in copper pipes. Here’s how it works:

  • Insert the copper pipe between the three rollers of the machine.
  • Adjust the position and pressure of the rollers to achieve the desired bend radius and angle.
  • Start the machine to gradually roll the pipe between the rollers, shaping it into the desired curve.
  • The three rollers work together to ensure an even and accurate bend along the entire length of the pipe.
  • Using a 3-roll bending machine provides excellent control over the bending process and is ideal for creating smooth and consistent bends in copper pipes.

Using a Pipe Bending Machine

A pipe bending machine is a powerful and versatile tool specifically designed for bending various types of pipes, including copper pipes. It offers precise control and automation, making it suitable for both simple and complex bending tasks. Here’s how it works:

  • Place the copper pipe inside the machine, aligning the marked bend point with the bending dies.
  • Set the desired bend angle and radius on the machine’s controls.
  • Start the machine to initiate the bending process.
  • The machine uses hydraulic or mechanical force to bend the copper pipe accurately according to the specified parameters.
  • Pipe bending machines come in different sizes and configurations, allowing for various pipe diameters and bend angles. They are commonly used in industrial settings and fabrication shops to achieve consistent and high-quality bends in copper pipes.

Using a Spring to Bend the Pipe

  • Tube-bending springs are inserted into the copper pipe to provide support during bending.
  • Mark the bend point on the copper pipe.
  • Clean the pipe end to remove any burrs.
  • Choose the correct size spring for the pipe.
  • Bend the pipe over your knee while moving it back and forth to create a smoother bend.
  • Remove the spring after bending.

Using Sand or Salt to Bend the Pipe

  • Straighten the copper pipe and tape off one end.
  • Fill the pipe with fine sand or salt using a funnel.
  • Tape off the other end of the pipe.
  • Bend the pipe to the desired curve.
  • Remove the tape and let the sand or salt flow out

Using a Pipe Bending Tool

A pipe bender is a dedicated tool designed to bend soft metal pipes like copper.
Insert the pipe into the bender, aligning the bend point with the gauge.
Bend the pipe using the tool, ensuring that the shoe of the tool moves along with the bend for a smooth curve.

Using Curved Shaping Items

Place the copper pipe over a padded knee or other curved shaping items like metal cans, buckets, or large pipes.
Gently bend the pipe to achieve the desired bend radius.

General Tips

Proper support along the entire length of the pipe is crucial for a consistent shape.
Bend slowly and evenly to avoid kinks or ripples.
Shape the bend gradually to prevent pipe collapse.
For crafting or critical projects, consider hiring a qualified plumber to ensure accurate bending.
Bending copper pipe requires practice and attention to detail. Each method has its advantages, so choose the one that best suits your project and skill level. Remember to follow safety precautions and take your time to achieve smooth, professional bends.