Evaluation of EN 81-20 Requirements with regard to Car Deceleration during Buffering Process of Lifts

Buffers at lifts comprise a certain design. This design and the resulting buffer properties have to cover the different modes of operation. For lift buffers this means the coverage of varying car masses at the specified speed. The paper shows the basic characteristics of hydraulic buffers. Following a sketch on the requirements on buffers according to EN 81-20 is given. A software for the detailed simulation of buffer collisions is presented. In the main part of the paper this software is used to calculate and to analyze two cases of buffer collisions at maximum and minimum loading each. The results out of these simulations are shown and discussed in brief.