Improving Uptime with Hennig's CDF Filtration Systems

CDF Filtration Systems Will Improve Uptime, Cost and Customization Benefits

Increase uptime, cost and customer-focused performance, using Hennig’s patented Chip Disc Filtration (CDF) system. Located on the exterior frame of the conveyor, the rotating permanent filtration disc can be used with a hinge belt or scraper belt conveyor system. That means Hennig can customize our system based on the customer’s requirements.

The chip removal/coolant filtration system’s stainless steel mesh provides effective filtration and long-term durability, eliminating the cost and time required to service drum systems. The design provides a direct coolant flow path into the coolant reservoir. It can filter a variety of materials, both in water and oil-based coolant.

The conveyor system can incorporate either a hinged or scraper belt conveyor with the disc filter. Standard features to the system will include coolant tank, low-pressure pumps, high-pressure pumps and float switches. When through-the tool coolant is required, Hennig offers cyclonic, bag filter or cartridge filter in order to filter the required 5-10 microns of the needed filtration. Additional features that can be added are chillers, oil skimmers and all electrical requirements.

The CDF system blow-off nozzles self-clean the disc of chips. These nozzles will clean any chips that may be lodged in the permanent media filter as the disc rotates. The nozzles are easily accessible in the event of clogging, since they are externally mounted.


More Competitive Advantages Compared to Alternative Systems

A  key difference between CDF filtration systems and many alternative systems is that our cost-effective system can be used with a scraper or hinged belt to remove fine, stringy, bushy and broken chips. Drum systems, by comparison, require two conveyors (a hinged belt conveyor and a scraper belt) when there are stringy chips. In turn, this dual installation increases maintenance cost and consumes added floor space.

Consider another crucial difference: better filtration provided by the Hennig CDF system. Competitors’ two-conveyor belt system can be effective down to 50 microns. Our one-conveyor system can go as low as 25-30 microns of nominal filtration.

The stainless steel permanent media disc and blow-off nozzles provide the advantage of easy removal for cleaning or replacement. The disc, external to the conveyor, can be removed within a half hour, by removing several screws. The seals, since they are externally mounted, are exposed to only clean coolant. By contrast, competitive units have seals on the dirt side of the filtering device, creating the potential for damage from sharp chips.

The CDF system’s external disc location allows lower overall height of the unit. Competitors’ internal drum filtration system can increase the unit height. Many small turning lathes require a low inlet height that can only be serviced by a conventional conveyor. The Hennig design handles this application, which competitors cannot.

Floor space requirement is another key difference between the Hennig CDF system and competitors. Their complex units incorporating the drum design consume more floor space, impacting total cost.

Dirty coolant and chips flow towards the filter discs, where the coolant is filtered and recycled back into the clean tank.  Chips and fines are collected via the belt and discharged.

Because the filters are located outside the conveyor system (unlike the drum filters), the CDF system easily removes large chips without damage to the filter.

Uptime and Maintenance Benefits

Significant Overall Equipment Effectiveness (OEE) operational benefits provided by the Hennig CDF system, compared to competitors’ systems, translate to improved cost effectiveness.

Shorter changeovers and TPMs (Total Productive Maintenance cycles) boost uptime/machine availability as well as schedule predictability. The Hennig system’s accessibility at the point of use provides a substantial advantage. With competitors’ internal drum filtration systems, a full set of maintenance can take a full day, versus shorter, easier maintenance on the Hennig system. Our system incorporates a stainless steel media filter, eliminating the need to replace filter mesh and related disposal costs. The Hennig back wash nozzle system is on the outside of the conveyor, typically requiring 20-30 minutes for maintenance.


Standard Features

  1. Disc filter (25-120 microns nominal)
  2. Main flood coolant pumps
  3. High-pressure pump (300-1000 psi)
  4. Cartridge filter (cyclonic or bag filters could also be used)
  5. Backwash CDF pump
  6. Disc access panels/backwash manifold
  7. Coolant tank
  8. Control box


  1. Accommodates hinge or scraper belt.
  2. A solid rotating magnetic drum is available for cast iron sludge/swarf. This self-cleaning, permanent-media filtration technology enables cast iron machining operations to eliminate large volumes of chips and fines from recirculating coolant without the use of disposable filter media.

Who Will Use the CDF System

  1. OEMs and resellers select the CDF system as an accessory to machine tools.
  2. End users/machine shops count on it as the chip conveyor/filtration for their machine tools.


Customer Feedback about the Benefits of Using the Hennig CDF System

About Clean Coolant and Cast Iron:

“The CDF platform, with its self-cleaning, permanent media design, is renowned for simplicity and ease of maintenance.  With some modification, we knew that a CDF version for cast iron would be the answer to eliminating even large volumes of cast iron chips and fines from recirculating coolant without the need for expensive disposable filter media or other complex systems.”


To learn more about the Hennig Chip Disc Filtration System, contact:

Scott Cooley, Business Development Leader, Chip Conveyors/Filtration Systems


or check out our CDF page for more info