Miniature Shock Absorbers for Train Sliding Door Systems
Metal 99 integrates ACE miniature shock absorbers supplied by BIBUS to secure pneumatically operated train sliding doors.
www.ace-ace.com
Application Area: Pneumatically operated sliding door systems and kinetic energy damping.
Metal 99 Ltd., a Hungarian manufacturer of rail-guided transport equipment, develops pneumatically operated sliding doors for public transit systems. To ensure passenger safety and operational stability for a Middle East transport project, the company needed to secure the end-position damping of its doors. The specific operational challenge involved arresting the kinetic energy of 55 kg doors moving at a maximum speed of 2 m/s. The initial system design relied on unverified dampers with a stated energy absorption of 59 Nm/cycle, but concerns regarding component failure under emergency stop conditions prompted the engineering team to seek a more robust alternative.
Technical Solution and Component Selection
To address this mechanical challenge, Metal 99 collaborated with pneumatics distributor BIBUS AG, which supplied the MC225EUMH miniature shock absorbers manufactured by ACE. Although the official catalog value of these self-adjusting shock absorbers is 41 Nm/cycle—lower than the initially specified 59 Nm/cycle data point—the components were selected due to their high built-in safety tolerances and proven structural integrity.
Overload Testing and System Validation
To validate performance under worst-case scenarios, engineers conducted drop tests on a load cell simulating an emergency stop with the 55 kg door mass accelerating at 2 m/s. The MC225EUMH shock absorbers successfully decelerated the kinetic energy and withstood the mechanical overload without any damage to their hermetic seals or internal components. This physical testing confirmed the reliability of the damping solution in demanding rail environments.
Operational Impact and Additional Protections
The integration of these validated shock absorbers prevents failures in the door opening and closing systems, ensuring continuous operation. Furthermore, the competitive procurement of the components allowed Metal 99 to integrate custom-manufactured rubber buffers into the end positions, providing an additional layer of mechanical protection against vandalism and extreme force.
Norbert Turi, Sales Manager at BIBUS, highlighted the technical rationale behind the selection: "This case shows us very well the safety reserves that ACE's shock absorbers have. It is worth taking a very close look at the catalog data of all suppliers when it comes to their performance."
Edited by Lekshman Ramdas, Induportals editor – adapted by AI.
www.ace-ace.com
