What is BOM Press Felt? Types and Structure Explained

BOM Press Felt Classification

At present, more than 95% of the press felt used on paper machines are BOM press felt. Therefore, it is necessary to classify the types of high-line pressure bottom mesh press felt based on the number of layers of the bottom mesh.

• Single Layer BOM Press Felt

Due to the different organizational structures of its bottom mesh, it can be divided into: 1/1 plain weave structure, 2/2 diagonal weave structure, 1/3 broken diagonal weave structure, 1/5 broken diagonal weave structure, and so on.

• Double Layer BOM Press Felt

Due to the different organizational structures of its bottom mesh, it can be divided into: 1+1 composite double-layer and double-layer structured paper making felt.

• Multi Layer BOM Press Felt

According to different bottom mesh structures, BOM press felt can be divided into multi-layer structures such as 1+2 composite three-layer, 1+1+1 composite three-layer, and 2+2 composite. The image below shows a multi-layer BOM paper making felt.

• No Node BOM Press Felt

Its warp and weft lines intersect but have no joints, and are laid in a non-woven method. The bottom mesh layer is smoother, and the wire diameter and number of splices used are more flexible. Using nylon multifilament or multifilament as warp and nylon multifilament or monofilament as weft, weaving into single-layer, double-layer, multi-layer, laminated and other structures using specific techniques as the base mesh, and then laying a layer of synthetic batt fiber on top and needling it. Its main characteristics come from the bottom mesh part, which is made of special materials and has a unique structure that ensures that the geometric shape of the felt’s cross-section remains unchanged when passing through the pressure zone. Therefore, the drainage channel is unobstructed, dehydration is fast, and it is conducive to increasing paper machine speed. The surface of the synthetic material that forms the bottom mesh is smooth and not easily adhered to impurities. Under the condition of guaranteed washing conditions, its service life is relatively long. The strength of the bottom mesh felt is generally high, and it can maintain stable usage specifications under high load or high line pressure conditions, with an elongation rate generally not exceeding 1%. The press felt surface is flat and not easy to leave felt marks on paper, with a wide range of applications.