Measure the Parallelism (PAL)

The directional tolerance parallelism is defined in the geometry as two straight lines in a plane, which are the same distance from each other and do not intersect.

Parallelism tolerance
The tolerance zone is limited by two parallel straight lines or planes at distance t, which are parallel to the reference.

Parallelism tolerance – rotation symmetry
The tolerance zone is limited by a cylinder at diameter t, the axis of which is parallel to the reference.

Parallelism is an important feature of production technology. Components which are aligned parallel to each other are at an equal distance to each other over the entire length. It can influence statics, accuracy of fit and interaction with other components.