UNDERSTANDING CLR
CLR means centerline radius. It's the radius measured from the center of the bend's arc to the centerline of the tube. It is not the measurement to the inside or outside surface.
For an ideal round-tube bend, the inside radius is CLR minus half the OD. The outside radius is CLR plus half the OD. Those relationships explain the drawing; actual bent sections can change shape and must meet the agreed requirements.
Here's a geometry example: a 3-inch OD tube with a 4.5-inch CLR is a 1.5D bend because 4.5 divided by 3 equals 1.5. That example does not identify a PTB catalog option.
When you send a drawing, label the radius as CLR and state the tube OD and wall. If space is tight, show the space the finished part has to fit rather than assuming the smallest radius is the only answer.
COMPARE THE TURN
A tighter bend changes direction in less space; a larger centerline radius makes a broader turn. CLR is measured to the tube centerline. Compare CLR with outside diameter, wall thickness and the available space before choosing a bend.
KEEP EXPLORING
TAKE THE NEXT STEP
Choose a catalog part or bring your requirements into a project review.
BROWSE MANDREL BENDSPREPARE YOUR RFQ