CorruPlate™ Disc Filter Sectors & Components

What is a Disc Sector

Disc filters are used as save-alls to recuperate costly fibers and fillers, which would otherwise be discarded. In addition, it also contributes towards cleaner effluent discharges. Prior to the introduction of disc filters, open cylinder deckers, sidehill screens, vacuum drum filters, belt filters and air flotation separation cells were used as save-alls.

Disc filters have many applications; thickening of slow-draining stocks, such as, mechanical pulps are the most popular usage. The right disc filtering system, disc segments and filtering media, is key to the recuperation of the fibers and fillers which translates into savings for the mill.

A disc filter unit consists of a series of discs mounted on a hollow center shaft that is equipped with drainage channels terminating at a valve assembly. Each individual disc is made of pie-shaped segments (disc sectors) covered with filtering media, such as polypropylene, kynar and occasionally but not as effective wire mesh.

The discs rotate in a vat filled to about the midpoint of the center shaft with a mixture of white water and sweetener fiber. The center shaft is rotated by variable speed drive. When the disc sector enters the vat, a mat is formed from the fibers in the vat, first by gravity and then by vacuum. This initial fiber mat, not the filtering media, is the actual filtering medium.

As the sector rotates further into the vat, the mat thickens, and the filtrate becomes clearer as fines and inorganic materials are retained to the fiber mat. A splitter mechanism in the valve assembly separates the clear and cloudy filtrates, which are carried to appropriate filtrate tanks via droplegs.

As the sector emerges from the vat, a valve at the end of the center shaft cuts off vacuum, and the mat is removed by knock-off showers. The mat is released into chutes and then to a conveyor that empties into a stock chest. The knock-off position is sometimes located at the top center position of the disc shaft. Alternatively, the knock-off position may be 150* from emergence of the disc from the vat. The showers clean the filter media, as the disc sector continues to rotate and start another cycle.

Our CorruPlate™ Disc Sectors


  • 316LStainless Steel, solid construction
  • Wide open drainage area
  • Corrugated channels
  • Lighter in weight
  • Can be manufactured to your specification
  • Solid sheet of corrugated metal
  • Engineered assembly to allow flexibility with rigidity


  • Prevents premature corrosion from chlorines
  • Increases flow = increased productivity
  • Flows directly to drainage port
  • Longer life expectancy
  • CorruPlate is superior to OEM sectors
  • No area to trap stock and cause build ups
  • Thicker, dryer mats

Disc Sector Installation

For the best operation of your disc filter segments, we suggest that the following points are carefully considered. These points refer to a new or replacement segment.

  1. A new gasket should be installed anytime segments are being fitted
  2. All touching surfaces should be thoroughly cleaned
  3. It should be noted that the base plate should be exactly 90° to the vertical of the shaft
  4. The segment after being placed in it’s operational position should be secured in place
  5. The tightening of the segment should be done at the cross corners on opposite sides. The initial torque in securing the segment should not be the final but rather one in a series of rotational tightenings.
  6. Once the segment is tightly secured, a check should be made to ensure that 100% vertical position is obtained
  7. A second segment should be installed repeating the process
  8. “VERY IMPORTANT” the tops of both segments should be checked for alignement.

Filter Bags, Standard Zippered Bags,
Ultrasonic Welding Cover

Filter Media (Bags)

Material Specifications
Polypropylene has excellent strength, low moisture absorption and is very resistant to abrasion. It maintains strength after repeated flexing.
Effect of Acids: Excellent resistance to most acids and alkalis with the exception of cholorsulfonic acid and oxidizing agents
Effect of Alkalis: Excellent resistance to alkalis
Effect of Bleaches: Generally good resistance to bleaches and solvents
Maximum Operating Temp: 180°F 82.22°C
Kynar has good mechanical strength, stiffness and creep resistance. It has a high toughness, also at low temperatures. Excellent chemical and hydrolysis resistance.
Effect of Acids: Superior resistance
Effect of Alkalis: Superior resistance
Effect of Solvents: Superior resistance
Maximum Operating Temp: 300°F 150°C

Storage Recommendations: To avoid material shrinkage, Filter Media MUST BE stored in a cool dry environment, temperatures not to exceed 20°C 70°F. (Do not store filter media near Disc Filter System or high humidity places. Also sunlight should be avoided). Maintenance Recommendations: In order to maximize filter media life, it is highly recommended that the sector units and filter media be cleaned with a high-pressure washing at each machine shutdown.

Storage Recommendations: No special storage recommendations required.

Maintenance Recommendations: In order to maximize filter media and disc sector life it is highly recommended that the disc sector be thoroughly cleaned. Thorough cleaning of the showers and nozzles, headers, center shaft and hud with a high pressure shower. (High Pressure Showers are available from P&P Filtration).

Preventive Maintenance: At every shut down, it is recommended that the VAT is emptied, the shaft kept rotating at a slow stable rpm power spray the sector segments as they rotate. Approximate cleaning time 30 minutes.

Standard Zippered Bags
Features & Benefits


  • Kynar zipper and sewing thread
  • Double stitched and reinforced seams
  • Intricate sewing technique to obtain square corners
  • Fabricated from one continuous piece of fabric
  • Re-enforced zipper application


  • More durable than polypropylene and and polyester
  • Increases seam strength
  • Square corners=easier clamping
  • Seams are weak point one less seam = longer life expectancy
  • A stronger zipper = longer life expectancy

Ultrasonic Welding Cover
Features & Benefits of Ultrasonically Fused Filter Media


  • No Stitches, no seams failure
  • No Zipper
  • Ultrasonically fused seam will outlast fabric
  • Square, well defined corners facilitate clamping
  • Fused seam maintains a straight edge during shrinking process
  • Fabricated from one continuous piece of fabric


  • Longer life expectancy
  • Quicker installation = less downtime
  • Does not obstruct filtration face increased filtration performance = shrinking process improved productivity

Auxiliary Products

  • Gaskets; rubber, Kynar, felt, all produced
  • Top clamps
  • Bottom clamps
  • Base assemblies
  • Bag clamps
  • Rivets; Kynar or stainless steel
  • Shipping container