What is the maximum deflection angle of each miter joint in ductwork?

What is the maximum deflection angle of each miter joint in ductwork?

• A. 45 degree
• B. 90 degree
• C. 135 degree
• D. 180 degree

Answer: (B)

A miter joint forms a bend by cutting each piece at equal angles so the two pieces meet to make a corner. For a standard miter elbow, each cut is 45 degrees, and when they come together they create a bend of 90 degrees. This is the largest turn you can achieve with a single miter joint, because making a sharper turn would require cuts steeper than 45 degrees, which isn’t practical for a clean, tight fit and would lead to leaks or distortion. To get deflections greater than 90 degrees, you’d use additional joints or a curved elbow rather than a single miter joint.

A miter joint forms a bend by cutting each piece at equal angles so the two pieces meet to make a corner. For a standard miter elbow, each cut is 45 degrees, and when they come together they create a bend of 90 degrees. This is the largest turn you can achieve with a single miter joint, because making a sharper turn would require cuts steeper than 45 degrees, which isn’t practical for a clean, tight fit and would lead to leaks or distortion. To get deflections greater than 90 degrees, you’d use additional joints or a curved elbow rather than a single miter joint.