Bending Types – Air Bending (or Partial Bending)

Today, “air bending” is the most frequently used bending technique thanks to the improvement of modern press brakes and their CNC’s, which can better manage the sheet metal springback. This name comes from the fact that there is always air between the sheet metal and the die bottom. It is also known as “partial bending” which comes from the fact that the sheet metal comes in contact with the upper and lower tools only in three points during the bending procedure.

ROLLERI-air-bending

Advantages:

• Air bending enables a larger range of profile angles. For example, you can use a punch and die at 30 degrees to achieve profiles with any angle from 30° to 180°
• Air bending is faster than other bending types. Springback is managed by going to a further depth with the punch tip in the die opening and making a closer angle, instead of increasing the bending force or the machine stand-by time.
• The required bending force is lower than in other bending types thanks to the ability to choose a wider die. This means a lower tonnage press brake will obtain a wider range of profiles, increasing productivity and reducing costs.
• The resulting sheet metal has fewer marks due to less friction with tools.
• Tools wear out less and have longer productivity life.

Disadvantages:

• A lower precision on the angle of profile when compared to bottoming or coining. It’s understood though that this tolerance is ¾ of a degree when using air bending techniques.
• As sheet metal isn’t coined, springback is higher and requires better knowledge from the operator to be controlled.
• Deformations may occur if there are holes near the bending line.