Roller structure including bearing structure at one side for transporting product

A roller structure used to transport a product, the roller structure comprising:

• a roller bar configured to allow the product to be arranged thereon and to rotate for transporting the product in one direction;
• a block fixing part coupled to the roller bar to fix the roller bar on a first end part which is one end part of the roller bar;
• and
• a bearing structure part configured to maintain straightness of the rotation of the roller bar during operation of the roller bar while maintaining the roller bar on a second end part which is another end part opposite to the one end part of the roller bar,
• wherein the roller bar includes a rotation shaft to rotate for transporting the product, and
• the bearing structure part includes a first ring part arranged to surround the rotation shaft and a second ring part arranged to surround the first ring part,
• wherein the first ring part is formed of polyetheretherketone (PEEK), and
• the second ring part is formed of ultra-high molecular weight polyethylene (UPE).