What is the Trade Size?
Trade size numbers in the smallest category count down from 50 to 1, with 50 having the smallest material diameter, and 1 having the largest.Trade sizes in the middle category count up from 1/0 (smallest) to 7/0 (largest).
Represented in inches, numbers 5/64" through 1-1/4" count up, with 5/64" having the smallest material diameter, and 1 having the largest.
What Is a Chain's Working Load Limit?
Also known as "Rated Capacity," the Working Load Limit (WLL) indicates the maximum load that a new and undamaged straight length of chain can potentially handle.
Though the chain is capable of supporting the maximum load, it should never be applied. Keeping the load under the working load limit helps ensure safety and long service life.
Grade is intended to indicate the strength and tolerance of welded steel chains. Grades 100, 80, 70, 43, and 30 are specified by the National Association of Chain Manufacturers (NACM). Other grades are determined by manufacturers.
A higher number for grade will equate to higher strength and tolerance in each chain.
Welded steel chains are engineered for specific purposes. The classification often indicates the purpose or an intended attribute. For specific applications, consult the manufacturer for size and grade recommendations.
Chains with Coil, High Test, Machine, Passing Link, and Proof Coil classifications are ideal for farm, home, and general utility applications. High Test Chains are also widely used in industry, construction, and lumbering operations.
Chains with Cathead classification are designed for maximum pipe contact and gripping power. Transport Chains are designed for securing loads in transport. They are also suited for tie-downs, towing, and logging operations.