Manufacturing of the metal spoon component in elevator door mechanisms using polymer-based materials

In this thesis study, the feasibility of using polymer-based alternative materials instead of conventional metallic materials commonly employed in elevator door mechanisms was investigated. Specifically, the tribological performances of MoS₂- reinforced PA 66 (molybdenum disulfide-filled polyamide 66) and POM (polyoxymethylene) materials were evaluated. For this purpose, a specially designed test apparatus that models a real elevator mechanism was utilized. The experiments were conducted under varying numbers of opening and closing cycles, and parameters such as mass loss and surface temperature were systematically measured. The experimental results demonstrated that the MoS₂-reinforced PA 66 material exhibited superior wear resistance compared to POM. In particular, the additive material was observed to enhance friction resistance and provide a more robust structure against temperature variations. Furthermore, the effect of increasing surface temperature on wear behavior was clearly identified and graphically analyzed. Within the scope of the thesis, the door spoon component, which is conventionally manufactured from steel using laser cutting technology, was re-engineered and produced using polymer materials through the plastic injection molding method. This change in production technique reduced the manufacturing time and, with the decreased component weight, contributed partially to improved energy efficiency in elevator systems. This transformation highlights that polymer materials can offer viable alternatives in industrial applications from both mechanical and economic perspectives. The polymer components were fabricated using the plastic injection molding technique, which enabled high efficiency in mass production. Compared to metal processing methods, this approach provided a faster and more cost-effective vii manufacturing process. Moreover, the ability to produce parts with more precise and repeatable geometric tolerances through injection molding has proven to be a significant advantage in practical applications. As part of the experimental studies, the wear performances of the materials were analyzed using the door test mechanism. The test parameters were determined to reflect real working conditions, with factors such as surface pressure, sliding velocity, and ambient temperature kept constant. During the tests, the specimens were periodically monitored, their surface temperatures were measured, and any mass losses were determined using precision scales. Additionally, the worn surfaces were examined under an optical microscope, and the formation of transfer films was studied in detail. The experiments were conducted under laboratory conditions at an ambient temperature of 20–26 °C and a relative humidity of approximately 60%. The experiments were conducted under laboratory conditions with an ambient temperature ranging from 20-26°C and a relative humidity of approximately 60%. According to the results, MoS₂-filled PA 66 exhibited superior wear performance compared to POM material. The filled PA 66 demonstrated a longer service life due to its lower coefficient of friction and higher PV (Pressure × Sliding Velocity) limit. While POM material showed good performance, it did not achieve the same high wear resistance as the MoS₂-filled PA 66. These results indicate that the transition from metal to polymer is both feasible and advantageous in terms of mechanical performance and tribological durability. Therefore, it has been demonstrated that polymers can be used as an alternative to metal materials, especially in moving machine components.