FlexRake® FRHD


coarse Screen with openings 1 – 4 inches

The workhorse that set the standard for simplicity in unpredictable environments

Reliability in the worst storms and toughest conditions

The FlexRake® Heavy Duty (FRHD) model is a coarse screen engineered for open channel and applications where debris size and velocity may be unpredictable. The FlexRake HDs are the industry’s workhorse.  They have proven their versatility with more than 35 years of handling the debris that makes it into a channel – from general refuse, aquatic vegetation, tree limbs, tree branches and shrubs to lumber, tires, oil drums, and automobile frames.

The FlexRake’s level of performance in both daily operations and unpredictable conditions, benefits many other industries. Wherever applied, it is a workhorse that just keeps running, without operator intervention. The inherent value of the FlexRake is its simplicity: long product life, low cost of ownership, and adaptability to a range of site conditions (varied flows, debris types, and volumes). Duperon Corporation is continuously reinventing what is possible for simplicity in screening.


  • Open channels
  • Water intakes
  • Coarse screens
  • Stormwater
  • Irrigation canals
  • Pump stations
  • Flood control
  • Hydroelectric
  • Drainage canals
  • Combined sewer overflows
FlexRake FRHD

The Duperon®

The Duperon®
FlexRake® FRHD

Flexible Design

Adapts to a range of unpredictable flow and debris conditions without operator intervention

No in-channel maintenance

With no lower sprocket, the FlexRake FRHD allows maintenance to be performed from the deck. There are no jam points underwater to require diving or confined space entry for improved worker safety

Reliable operation

Designed for 24/7 operation. Units can stand idle for long periods, yet reliably respond when needed during a storm or debris event


Engineered to fit the unique needs of your site

Low cost of ownership

Fractional horsepower, few parts, minimal maintenance; the FlexRake HD is easy to install, own, and operate by your own crew

Uninterrupted water flow

Continually cleans across entire intake with multiple scrapers to avoid blinding and to limit headloss to ensure water is kept moving


The FlexRake HD received Manatee Safe designation from the US Army Corps of Engineers (USACE), US Fish & Wildlife Services (FWS) and Florida Fish and Wildlife Conservation Commission (FWC)

Read how FlexRake FRHD Heavy Duty units kept pumps operating to protect Louisiana Parishes during unprecedented floodwaters from Hurricane Katrina & Rita Read case study

Our solutions are simple

Our Solutions Are Simple

The FlexRake® was invented to offer a simple raking device that solved the challenges of screening open channels, intakes and rivers such as: 

  • Static trash racks that required workers to manually clean, often in dangerous weather events and hazardous physical conditions
  • Unreliable and maintenance-intensive designs
  • Long cycle times across intakes that couldn’t keep up during storm or vegetation events when they were needed most
  • Submerged sprockets that were subject to fouling, jamming, in-channel maintenance and even required divers to repair

The FRHD has proven a dependable solution in rain or shine. It has withstood seasonal weed blooms and protected communities from hurricane floodwaters. Its reliability and unmatched adaptability translates into everyday pump protection and failsafe performance in events of magnitude.

How can we help

See how FlexRake FRHD units helped an Idaho cooperative deliver reliable water supply to local farmers, reduce labor costs and eliminate worker safety concerns Read case study


The FlexRake HD is a front-clean, front-return, mechanically cleaned bar screen. Features the industry-leading FlexLink™ multifunctional link system, which eliminates underwater sprockets, bearings or tracks that create a fixed path of travel and are subject to fouling and/or jamming. The groundbreaking flex/pivot action of the Duperon FlexRake is unhampered by large debris.

The FlexRake HD is a coarse screen that utilizes A36 steel with Duperon standard coating or hot-dipped galvanized (but is also available in 304 and 316 stainless steel). It has bar opening options from 1-4 inches. Serrated UHMW-PE scrapers are used to clean the face and in between the bars.

General Specs

Typical Applications Open channels, water intakes, coarse screens, irrigation canals, stormwater pump stations, flood control, hydroelectric, combined sewer overflows


Unit Width 2 ft to 12 ft
Unit Length 10 ft to 100 ft
Bar Openings 1 in – 4 in
Bar Shape Rectangular Bar
Scraper Configuration UHMW-PE serrated scrapers
Material of Construction A36 steel, with Duperon standard coating or hot-dipped galvanized

Available in 304 or 316 Stainless Steel

Cleaning Frequency 2.3 ft/minute
Lifting Capacity 1000 lbs

3000 lbs option available

Angle of Installation Optimum: 30 degrees from vertical. Range from vertical to 45 degrees, dependent upon site conditions
Typical Motor 1/4 HP 1 PH, 115/230 VAC OR 3 PH, 230/460 VAC, weatherproof motor
Standard Controls Packages range from simple start/stop to sophisticated automation.

Motor overload protection provided.

Operation Options Continuous/Manual

Automatic with timer, float, SCADA, differential/high-level sensing options with I/O as needed

Key Features

Industry-leading FlexLink™ eliminates lower sprockets, submerged bearings and tracks

FlexLink™ multifunctional link system has ultimate strength of 60,000 lbs with unmatched durability

Jam Evasion™ technology lifts and pivots around debris to remove from channel without shutdown or jamming

Swinging drivehead allows the entire raking system to move outward to discharge large debris

Full-Screen Cleaning™ reduces the risk of blinding at the intake by cleaning all of the screen all of the time

Fractional horsepower motors used for energy efficiency

Everything is serviceable from the deck to eliminate in-channel maintenance and confined space entries


FlexRake FRHD

Photo Gallery

Case Studies

Mud Lake Water Users Case Study

FlexRake®FRHD units help an Idaho cooperative deliver reliable water supply to local farmers, reduce labor costs and eliminate worker safety concerns

St. Charles Parish Case Study

Duperon FlexRake® FRHD units operate flawlessly to keep Louisiana community above water during Hurricane Katrina and Rita

Related Products

Duperon® FlexRake® FP

FlexRake FP

Bar openings greater than ½ in

In-channel coarse, slotted bar screen with FlexLink™ and UHMW Thru-Bar™ technology. Ideal for ‘sticky’ or matting debris. SSTL construction.

Duperon® FlexRake® Only

FlexRake FRO

Bar opening dependent on existing trash rack.

FlexRake raking device with FlexLink™ technology is mounted onto customer’s existing bar rack using I-Beam or sidefab mounts.

Duperon® Self-Cleaning Trashrack


2 in – 3 in bar opening

Front clean, rear return design. For sites that experience severe conditions with high volumes, high velocities and large debris present. 

You’ll like
working with us

The Duperon® FlexRake® HD does an excellent job of screening all the materials out [from constructed wetland ponds] before they can reach the pump. We funnel all our water through that screen, and it catches a little bit of everything—natural debris, trash that comes in

Boogie Broussard
General Foreman, City of Beaumont Water Reclamation, TX

Tell us about your project

‘You’ll like working with us’ is a commitment and the way we deliver extraordinary customer care for the full life-cycle of your equipment. This is how we strive to earn the privilege to serve your continued screening needs.


Design Collaboration

To build your solution, our engineers take the time to understand your facility, process, and goals.

We’ll combine our team’s experience with water screening, cleaning, and processing with your team’s detailed understanding of your product and process, so we can develop a reliable and cost-effective solution.