Optimizing Carton Flow Applications Through Proper Planning & Execution

Carton flow is a warehousing tool frequently used to improve order picking rates, picking accuracy, reduce both foot and equipment traffic, and more effectively utilize rack and warehousing space. Most carton flow is mounted into pallet rack, but it can be designed to as a standalone system or even a wheeled mobile cart… it’s knowing what you ultimately need from the system that determines how you are going to get there. The Mallard team is here to help be your carton flow GPS. So, let’s get moving!

Standalone Carton Flow System


  1. Carton Flow Application 

Define the need that each carton flow application will fulfill, i.e. full or split-case picking, tote parts storage, each picking. The need often dictates the best carton flow structure. Here are a few examples:

  • Standalone Carton Flow System – carton flow can be designed as a standalone system mounted within a lightweight modular frame as opposed to pallet rack. A standalone system is useful often for split-case and each picking, batching and kitting. Standalone carton flow units can be installed on a mezzanine as one way to take advantage of vertical space. The angle of the flow lane depends on the inventory weight and system depth.

    Multi-System Pick Module
  • Pallet Rack Mounted – carton flow can be mounted in pallet rack without pallet storage above. To mount carton flowin pallet rack, you must first know the rack type, elevations and bay dimensions so the system can be properly designed to fit and mount to that specific rack. See more pallet rack integration specifics below in “Size Up Your Rack”.
  • Multi-System/Pick Modules – Carton flow rack can be mounted below or within pallet storage systems to form a pick module. A carefully designed pick module creates efficient, high-volume case picking by consolidating a large number of SKUs in a relatively small warehouse footprint. The pallet storage above the carton flow application can be simple selective rack, or a dynamic system such as push-back or pallet flow.
  • Carton Flow Mobile Cart

    Mobile cart work cells – This is an option that is best used for fluctuating demand, space constraints, seasonal fulfillment, short-run manufacturing, assembly line changes, or small pieces/parts packaging. Mobile carts can be constructed with a tow assembly to allow for easy movement by forklift. Several carts can be linked together for fast system set up within the warehouse.

  1. Inventory breakdown

Tell us about your inventory… and we mean really tell us ALL about it. Designing the carton flow system is completely dependent on the type of inventory. Caution

  • Turn rates by SKU will help determine how deep the system needs to be and the set up for picking and replenishment.
  • How many full case, split-case, eaches of each SKU need to be picked to meet order fulfillment demand?
  • What is the SKU profile? What are the carton or packaging dimensions? Are there any special considerations, i.e. temperature requirements, fragile handling, food, etc.
  1. Size Up Your Rack

If you are planning on mounting the carton flow into existing pallet rack, there are several key features to look for to ensure the rack can effectively accommodate the carton flow rack or if modifications need to be made.

  • Frame/Beam Configuration – If the system is over 8′ deep, the Rule of Thumb is to plan for an intermediate beam to act as an interior support beam for carton flow lane. Also, confirm the beam height in a standalone system. Due to the nature of generally lightweight inventory, it is often customary for rack designers to specify short height beams (e.g. 3.5″ beam vs 4”).
  • Beam Adjustability – Most existing rack isn’t equipped with infinitely adjustable beams. This can limit how the carton flow elevations can be set-up and if the needed pitch can be established. A fix for that situation is to add an infinitely adjustable beam on load or charge side of the rack system.
  • Upper Pallet Storage – Interior beams may be required to stabilize the interior rack columns when pallet storage rack is above the carton flow bays. If there is an interior beam it will be positioned below the carton flow level and thus impact the vertical clearance. Be sure to plan for that adjustment.


  1. Choosing the Carton Flow Track

Once the details above have been gathered, your carton flow system design should start to take shape. Based upon the inventory and rack specs, if applicable, the type of carton flow track can be selected. If the inventory size is consistent Mallard offers three options: Cart-Trak, Econo-Flo and Flo-Guide. Each of these products offers specific benefits for inventory that is a consistent width. If the inventory dimensions vary than a full wheel bed system is recommended.

A full wheel bed system can accommodate, for example, one lane of 12” wide, one lane of 16” wide, one lane of 10” wide, etc. up to 144” wide for standard applications. Dyna-Flo, Dyna-Flo HD and Dyna-Deck are all full bed wheeled systems.  Snap-on lane guides help identify lane separation for fast, accurate stock replenishment in full bed systems. Full-lane guides are also available where needed.

2. Vertical Clearance

There must be enough vertical room to pull be able to lift up and pull out the carton, or individual product in the case of split-case picking. Too much vertical clearance however will limit the number of carton flow shelves that the bay could accommodate therefore waste valuable space. Proper, thoughtful spacing, both vertical and horizontal, between SKUs is important to optimize the carton flow system.


Carton Flow Mount

Whether the rack is existing or being designed specifically for the carton flow application, there are industry Best Practices to follow to ensure the most functional and long-lasting system configuration. Carton flow can be designed to fit within structural, roll-formed or hybrid rack systems. It is important to identify the system type so that the proper mounting brackets are specified.

  1. Frames: Infinitely adjustable frames are ideal in order to provide subtle pitch changes as needed.
  1. Beam Width: Ideal beam width for carton flow is <10’. If bay width is 10′ or wider, the pressure at the pick (discharge) side may cause the beam to bow out. A beam tie is recommended for wider beams (e.g. 12’ and 14’ beams).
  1. Beam Height: Rule of Thumb is to plan on 3.5” beam or larger for carton flow… both charge and discharge beams. If using a 2.5” beam the carton flow bracket may stick out below the bottom of the beam and reduce vertical clearance.

    Hardware Free Carton Flow Mount
  1. Beam Type: Beams vary in structure and design with each manufacturer. The type of beam and connection will dictate the bracket to use for the carton flow connection.
  1. Beam Mounting: Mallard manufactures a variety of carton flow beam mounts to fit either structural or roll-formed rack… including a hardware- free retention angle option (click on link for more info and video instruction). Check out our selection and always feel free to reach out to the Mallard team with any questions.


Two key elements of the carton flow design process that the Mallard gravity flow team can provide are our proprietary  M-Elevations schematics and our in-house Engineering Testing Lab.

Carton Flow M-Elevations
  1. Mallard M-Elevations is a proprietary tool that can show customers exactly what the carton flow will look like within the rack, and even better, what the entire system will look like within the warehousing footprint. M-Elevations are one way to ensure that the design parameters are on spec before the system is built out and ordered. Ask about M-Elevations when you speak with a Mallard gravity flow specialist.
  1. Engineering Testing LabWe cannot stress enough what a valuable step this is to ensure that the system is optimized to meet your specified needs. The Mallard engineers test for flow consistency, proper pitch, hang-ups, efficiency, ergonomics, tracking, safety, etc. When the system is approved through the Engineering Testing Lab… the system is ready for a long, productive life in your facility.

When you are ready to order your carton flow products, please check out our blog: Easy Carton Flow Ordering. You will find important links and a video tutorial to help you place the proper order. However, don’t hesitate to reach out to our gravity flow team if you have additional questions… we are here to help, so just give us a call!