EE started work @ 7am. EE walked on catwalk during morning. Came to office to report broken drag chain. Repair was completed & another repair was decided on fixing tooth on bucket. Bucket needed to be repositioned. EE went to controls. EE walked around on catwalk to engage clutch. After engaging clutch & returning to cab the welds broke on catwalk. EE's arms/armpits caught fall.