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# ALUMINIUM MOTION GUIDANCE SYSTEMS - LOADS / MOMENTS:

**Loads:**

Max Speed: 2 m/s

Max Acceleration: 30 m/s^{2}

Max Temperature: 60ºC

The units can be sealed using lubrication blocks:

**Torsional Moments:**

Tortional Moments can be converted into an equivalent applied load (in Newtons) using the following calculation:

**F _{v1} = M_{t} / a**

where M_{t} is the torsional moment in Nmm and a is the distance between the rails in mm.

**Longitudinal Moments:**

Longitudinal Moments can be converted in a similar manner using the distance between the carriages along the rail:

**F _{v2} = M_{l} / b **

where M_{l} is the longitudinal moment in Nmm and b is the distance between the carriages on the same rail (mm).

**Size**:

To determine the size required, use the following calculation for P:

P must not exceed the P max for the given size:

Size |
P max (N) |

15 |
750 |

20 |
1700 |

25 |
2500 |

P = k_{f} . (F_{v} + F_{h} + t . M_{t} + s . M_{l})

where k_{f} is the operating factor (see table), F_{v} is the total vertical load (including F_{v1} and F_{v2} from above) and F_{h} is the total horizontal load. Factors M_{t} and M_{l} only come into effect if only one carriage and one guide rail is used - their constants t and s are listed below. For all other applications, the moments should be converted into equivalent vertical loads (F_{v1} and F_{v2}) using the calculations above.

**Recommended Operating Factor (k _{f}):**

Factor kf | Application |

1.0 | Linear motion guide with manual drive |

1.2 | Linear motion axis with ball screw |

1.5 | Linear motion axis with toothed belt drive |

2.0 | Axis of machine tool not subjected to dirt |

7.0 | Linear motion axies with linear motor drive |

8.0 | Linear motion axies with pneumatic drive |

**Moment Constants, t and s: **

Size |
t |
s |

15 |
140 | 180 |

20 |
110 | 120 |

25 |
100 | 110 |

Maximum service life is 4000 km for a standard block with initial greasing. This can be extended to 12500 km by use of two lube units. If the lube units are relubricated after 12500 km, then a life of 25000 km can be expected.

**Nominal Life:**

This can be calculated using either of the following equations:

L = (C / F)^{3} , where L is nominal life in km, C is dynamic load capacity (N) and F is the equivalent load (N)

or

L_{h} = L / (2.s.n.60) , where L_{h} is nominal life in hours, s is the length of stroke (m) and n is the repetition rate (complete cycles per minute)