BIS Certification For Heavy-Duty Cranked-Link Transmission Chains The Bureau of Indian Standards has developed IS 15510:2004 for heavy-duty cranked-link transmission chains. These chains are widely used in industrial machinery, conveyors and for moving heavy equipment from one place to another. This standard outlines the quality of the material. Compliance with IS 15510:2004 is extremely important to ensure reliable performance, extended service life and safe operation even under difficult conditions. Heavy-duty cranked-link transmission chain manufacturers must obtain BIS certification from BIS to sell in India.