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# ALUMINIUM MOTION GUIDANCE SYSTEMS - PARALLELISM:

The system should be aligned in the following 3 directions in order to ensure the travel life is not reduced.

**Parallelism of the rails**:

The following table shows the tolerances for aligning the rails and carriages.

P1 values (mm) for: |
||

Size |
Normal |
Preloaded |

15 |
0.020 |
0.008 |

20 |
0.026 |
0.010 |

25 |
0.031 |
0.014 |

**Height Alignment (lateral):**

The permissible vertical offset, S (mm), is given by S = a f , where a is the distance between the guide rails and f is the calculation factor (see below).

Calculation Factor |
Normal |
Preloaded |

f |
0.0012 |
0.00035 |

**Height Alignment (longitudinal):**

The permissible offset along the rail is given by R = b g , where b is the distance between the carriages (see left) and g is the calculation factor (see below).

Calculation Factor |
Standard |
Preloaded |

g |
0.0006 |
0.00021 |