MaxFlo™ Drum

Ensuring better pulp quality

At today‘s high production rates, many vacuum washers are operating over design capacity. When drum replacement becomes necessary, the ANDRITZ MaxFlo™* drum is the latest in vacuum washer technology. With a high capacity antirewet deck, reinforced structural components, and an optimized hydraulic design, the MaxFlo drum maximizes efficiency and reliability. With the ability to be retrofitted into nearly any OEM washer system, the MaxFlo drum is the ideal solution in both brownstock and bleaching applications.

Background for the invention

Driving force in vacuum washers is vacuum that is created by barometric leg. Pressure loss in drum end, channels and drum deck is direct loss in vacuum. Optimizing each critical component for minimum loss will lead to higher capacity drum and even vacuum along the drum length. This means minimizing the losses:

  • Sudden expansion or contraction
  • Bends
  • Any obstructions
MaxFlo™ Drum

The new ANDRITZ vacuum washer drum is a result of comprehensive R&D work that focused on improved fluid hydrodynamics and cost-effective construction. As the result we have generated a modular designed drum with higher ROI:

  • Increased Production
  • Increased Efficiency
  • Minimized Water Usage
  • Minimized Air Entrainment
  • Improved Reliability

Benefits and features

  • Less internal pressure drop leading to more vacuum applied to pulp mat
  • Higher discharge consistency
  • Improved washing efficiency
  • Higher dilution factor
  • Anti-rewet ability
  • Increased filtrate capacity
  • Improved reliability

MaxFlo™ Drum upgrade mill results

Vat Consistency2.111.73
Mat Consistency10.311.9
Dropleg Filtrate (gpm)  2,8253,625


160% of Design Loading!

Pulp mat before the upgrade
pulp mat after the upgrade

* Trademark of the ANDRITZ GROUP. For information regarding ownership and countries of registration, please visit

  • MaxFlo™ Drum for Vacuum Washer PDF : 1.6 MB
  • MaxFlo™ CSO Drum PDF : 1.1 MB