• Paper machine clothing consists of large continuous belts of custom designed and custom manufactured, engineered fabrics that are installed on paper machines and carry the paper stock through each stage of the paper production process –
  1. Pulp created and pressed to a mesh,
  2. Dewatered,
  3. Heated, and
  4. Dried by paper-making machines to make paper web.
• The types of fabrics are as follows:
  1. Forming fabric:  single-layer and double layer fabrics, two-and-half layer designs.
  2. Press fabrics: comprising single-base and multi base fabrics.
  3. Dryer fabrics: which consist of woven mesh dryers fabrics, needled woven mesh dryers, spiral link dryer fabrics, and needled spiral link dryer fabrics.
• The demand for these fabrics is primarily driven by paper mills. With the advent of technology synthetic material is being used to replace wire fabrics.

Product Characteristics

• The paper making fabrics are made from polyester and polyamide wires which are woven to produce the fabric.
• Paper making fabric should have the following functionalities:
  1. Dewatering ability or good drain ability
  2. Transferability of wet paper web - transfer wet paper web safely to the next position by adhering the wet paper web to the felt.
  3. Run-ability - avoid undesirable conditions as snaking, deviation, vibration and wrinkling.
  4. Wear resistance and resistance to hair shedding
  5. Compaction resistance.
  6. Paper surface smoothness - avoid any felt or roll markings.
  7. Uniformity
  8. Sustain high speeds of movement on paper making machine
• These vary according to the grades of paper, types of paper-making machines and the positions where the felts are used.
• In short, each position of the paper-making machine requires different felts.
• The different types of paper making felts are as given below:

1. Flow punch - These are single layer Batt-on-mesh (BOM) type felts with a relatively light weight base fabric which are woven by monofilament and/or twisted monofilament yarns. It is relatively easy to convert Batt-on-base (BOB) type felts to BOMs. BOM felts are the most widely used.
   
   
2. Dual punch- The base fabrics of dual-punch felts are woven by monofilament and/or twisted monofilament yarns into double layers to make large voids in felt and to resist against high pressure loadings. Moreover, dual-punch felts are highly efficient for preventing roll markings, so the felts are widely applicable for various kinds of paper-making machines including ones with high speed and high pressure loadings.
   
   
3. Lamitech punch- Base fabrics of Lamitech-punch felts consist of top and bottom base layers with different mesh structures woven by monofilament and/or twisted monofilament yarns. The combinations of the top and bottom base layers are quite plentiful to meet customers' various requirements. Lamitech-punch felts are generally used at those positions which require high surface smoothness of paper, high speed and high pressure loadings and those positions where a large void volume is required for the felts.
   
   
4. Aqua punch- Aqua-punch felts feature no knuckle points of warp and weft yarn on the base fabrics. Therefore, they can maintain quality smoothness under high loadings and are suitable for positions where a high paper surface finish is required.
   
   
5. Open punch- Open-punch felts are on-machine seamed felts which have been developed for easier felt installation onto paper machines. When the felts are installed onto the machines, loop holes at both ends of the felts are joined with pintle-wire to make them endless.
   
   
6. Nip punch- Nip-punch felts are of the BOB type developed as the first needled felts, the base fabrics of which are made of spun yarn and/or a combination of spun and filament yarns.
   
   
7. Warp punch- Warp-punch felts are of the BOB type which has been developed with the aim of minimum contamination in base fabrics, with the characteristic of having a very small amount of weft yarn if any.
   
   
8. Flat punch- Flat-punch felts are of the BOB type which have been developed for better smoothness to the paper surface and have the characteristic of light weight base fabric.

Raw materials and machinery

• Polyester or polyamide wires are used for making the fabrics.
• Weaving is carried out on heavy duty modern wide looms, which are capable of producing fabrics of desired specifications.
• Weaving is followed by fibre-locking process.
• Fibre-locking process is carried out on automatic machines which ensure correct locking of the fibre layers with the base fabrics to achieve desired characteristics.
• The key machinery used for paper making fabrics is as given below:
  1. Warp penetration machines
  2. Weaving machine
  3. Finishing and head setting machine