When evaluating stretch film machines, one important technical parameter is the Mechanical Design Line Speed (MDLS). MDLS refers to the maximum theoretical running speed that the machine’s mechanical structure is designed to handle, usually measured in meters per minute (m/min). It reflects the capability of core components such as cooling rollers, traction systems, and winding units to operate at high speed while maintaining stability.
MDLS indicates the design capacity of the machine rather than its normal operating speed. For example, a machine designed for 600 m/min MDLS may typically run at around 350–450 m/min during production. Operating below the maximum design speed helps maintain stable mechanical performance and reduces stress on components such as bearings, transmission systems, and drive motors. This supports smooth operation during continuous production.
A higher MDLS also reflects stronger mechanical engineering and precision manufacturing. Machines designed for higher line speeds require accurate dynamic balancing of rollers, stable drive systems, and rigid machine structures. These features help reduce vibration and maintain stable film stretching during high-speed operation.
Stable high-speed performance is particularly important when producing thin stretch films. The stretching process requires precise synchronization between rollers and traction systems to maintain uniform thickness and consistent film properties. A machine with a well-designed MDLS structure supports stable stretching conditions and reliable film quality during production.
Overall, MDLS represents the design capability of the machine’s mechanical system. A well-engineered line speed structure helps maintain stable operation, consistent film formation, and reliable production performance in stretch film manufacturing.
