High frequency of Work-Related Musculoskeletal Disorders (WRMSD) has been reported for assembly tasks performed in the production of automobile parts. Low and high back, neck, right ankle, and right wrist (in that particular order), were the most common sites of trouble in workers within this kind of process, as reported by Serratos, Hernandez, and Negrete (2014). The work herein presented refers to the ergonomic evaluation of Constant Velocity (CV) Joint assembly process. This entails putting together semi axes, bells, tulips, and other components. A report by Hernandez-Arellano, Brunette, Ibarra-Mejia, and Balderrama (2014), shows that the average cycle time to assemble a CV Joint is 30 seconds (±10 s). The semi axis is the first piece to be manipulated by the worker. It weighs typically a minimum of 3 kg. By the end of the assembly process, the CV Joint weighs up to 14 kg. The facility where the study was performed produces over 50 different models of CV Joints. The operations performed by workers are manual loading-unloading of pieces (to/from the machines), and inspection of parts. Occasionally, the workers operate the control panel of the Hydraulic Presses.
The main objective of this study is to perform the ergonomic risk assessment of manual materials handling activities involved in the assembly of Constant Velocity (CV) Joints at a manufacturing company located in Central Mexico.