Short for cross direction, also called cross-machine or transverse direction. Because fibers favor the machine direction, CD strength is usually the weaker value and often the one that fails spec, especially in carded webs. Cross-lapping, randomizing rolls and laydown control are the main tools for raising it, and weight and strength profiles are mapped across the full width.
CD tensile on the operator edge is 20 percent low, so pull a profile across the whole width.
Also heard as
- cross direction
- cross-machine direction
- TD
Related terms
MD
Machine direction: the direction a nonwoven travels through the line, along the length of the roll.
Cross-lapper
Machine that lays a light card web back and forth across a slower conveyor to build a wider, heavier batt.
Grab tensile
Tensile test in which jaws narrower than the specimen grip its center, so neighboring fibers help carry the load.
Strip tensile
Tensile test in which the full width of a narrow strip is clamped and pulled to break.