A ccording to the manufacturing process, the sheet piles could be divided into three categories:
a. Hot-Rolled Sheet P i les
b. Cold-Formed Sheet P i les
c. Cold bended Sheet Piles
Since cold bended sheet piles have got the same shape and appearance as cold-formed sheet piles, but they have the restriction on length and production efficiency, we do not consider this type of sheet piles here. Differences between Hot-Rolled and Cold-Formed Sheet Piles: 1. Manufacturing Process Difference: Hot-rolled sheet piles are made in the same way as people produce hot-rolled coils (HRC), of which the raw material is iron ore and steel billet. The manufacturing process of cold-formed sheet piles is continuous cold forming process by rollers without any heating treatment, of which the raw material is hot-rolled steel coils (HRC). 2. Interlocking System Difference: The clutch or interlock of hot-rolled sheet piles are Larssen type, which is different from cold-formed sheet piles. 3. Thickness Difference: Cold-formed sheet piles have got uniform thickness at every part of the pile, while hot-rolled sheet piles might have different thicknesses at flange, web and the clutch. Advantages of Cold-Formed Sheet Piles: 1. Environmental-friendly producing methods which will not cause any air pollution and water pollution. 2. Much stable for installation because of the uniform thickness, especially at the clutch. 3. Equivalent or better mechanical sectional properties with lower weight. 4. Customized length and designs are available. 
