When sourcing an industrial bag sewing machine, you must prioritize stitch type (typically single-thread chain stitch or double-thread lockstitch) and sewing speed, which usually ranges from 1,500 to 2,500 stitches per minute (SPM). Ensure the machine can handle the material thickness of your bags, whether they are woven PP, paper, or jute. Look for features like automatic thread cutting, integrated lubrication systems, and adjustable stitch lengths (7mm to 12mm) to ensure operational efficiency and seam strength.