What is Creping Blade?

Tissue Paper Machine Creping Blade

The creping blade is a critical component in tissue paper machines, directly determining the softness, bulk, and tensile strength of the tissue paper. The   creping blade by scraping the paper web, breaking the bonds between the fibers, allowing it to detach from the Yankee cylinder, creating the characteristic slight wrinkles of tissue paper and influencing its quality. The performance of the creping blade has a decisive impact on the paper's softness, density, thickness, and absorbency.

Yankee Dryer Cylinder

In tissue paper production, the creping process takes place on a Yankee cylinder, which is a steam-heated rotating pressure vessel, typically 14-18 feet in diameter. The Yankee cylinder first exerts its effect by forming a back pressure on the press roll. The paper is held tightly against the cylinder wall and dried by heat conduction before creping. The interaction between the creping blade, the Yankee cylinder, and the paper web determines the stability and efficiency of the creping operation.

Creping Blade for Tissue Paper

The creping blade fixed on the Yankee dryer and spanning its width, is located at the creping position and constitutes an important part of the creping mechanical component. And the coating of the Yankee dryer is made by mixing natural pulp by-products such as lignin, hemicellulose, and applied chemicals. It forms a thin and sticky coating on the surface of the cylinder wall, which helps the paper to be smoothly transferred from the idler to the Yankee dryer and maintains its position during drying and creping processes.

The adhesion strength of the coating directly affects the adhesion between the paper and the Yankee dryer. The creping area, which is the area between the blade of the creping blade and the surface of the Yankee dryer cylinder, is where the creping action actually occurs. The creping blade holder is responsible for firmly fixing the creping blade on the surface of the Yankee dry cylinder.

Working Principle of Tissue Paper Creping Process

At the moment before creping, toilet or tissue paper will reach its final dryness, with a moisture content of 2-6%. At this point, the fibers in the paper are connected to each other through hydrogen bonds, forming a tight stack of 7 to 9 layers of fibers. The process of creping is to disrupt or break these hydrogen bonds, causing the paper to expand in the Z direction and partially separate 7 to 9 layers of fiber layers. This energy is transmitted by the rotating cylinder, and the paper is firmly fixed to the cylinder wall through the cylinder coating. When a moving paper collides with a stationary wrinkling blade, energy transfer occurs, causing partial fiber fiber hydrogen bonding failure and breakage of the coating fiber interface of the Yankee dryer cylinder, thereby achieving the creping effect.