Modelling of a lock system in a door subject to break-in with crowbar
Examensarbete för masterexamen
Applied mechanics (MPAME), MSc
ASSA ABLOY  is today the global leader in door opening solutions dedicated to satisfying end-user needs for security, safety and convenience. Their lock systems are certified together with different doors against break-ins according to SS-EN 1630:2011+A1:2016 . This standard specifies how long time the tests maximum should take and what tools that are allowed to be used. These tests are, however, very expensive though both a new door and a new lock system are destroyed. The purpose of this thesis is therefore to develop a method for analyzing the lock system in a door with the help of commercial computational software in the specific case of a break-in with a crowbar. A model of one of ASSA ABLOY's lock system and a steel door with glass window are created in the commercial Multi-Body Dynamics software Adams. A convergence study is performed on the model with help of optimization methods in the software HEEDS. This model's purpose is to compute stresses and deformations in the lock system and from that analyze sensitive and exposed areas. With further development the model can be used to do a design optimization on the lock system. To get a better visualization of the break-in simulation the MaxFlex tool in Adams, a tool that can handle non linearity, is introduced. The knowledge about the tool is very limited from the beginning and after some simulations a conclusions that Adams is not the optimal software for this problem is drawn. Without any movements and mechanisms in the model a commercial Finite Element software is more appropriate due to shorter simulation time. Adams is adapted to relatively short time steps which is needed when movements and mechanisms are involved, but unnecessary for this model. A new model of the lock system is created in the Finite Element software Abaqus. This model is compared to measured data from a physical test and it can be seen that the deformation on the lock system has similar shape as in the physical test, but with a smaller total deformation.
Teknisk mekanik , Tillförlitlighets- och kvalitetsteknik , Produktion , Applied Mechanics , Reliability and Maintenance , Production