…And Which Should I Choose?
If you’re familiar with pallet rack storage solutions, you’ve likely heard of the sloped leg and cant leg frame, or maybe the offset or set-back frame design… confused yet? We hear you…. even the industry veterans use these terms interchangeably, and yet, these terms actually describe two unique pallet rack frame options that serve a similar purpose.
The umbrella term that covers both designs is Cantilever Frame Design. The main characteristic of the cant leg (also known as the offset or set-back frame) and slope leg is the recessed design of the lower section of the front column of the pallet rack frame. The purpose of cantilever frame is to provide greater forklift clearance at the aisle face to prevent forklift/pallet frame damage where impact risk is highest.
Here are some of the added benefits…
Benefits and Features of Cantilever Frame Pallet Rack:
- Reduces forklift frame damage
- Provides wider travel lanes in aisles
- Maintains total storage capacity
- Reduces rack maintenance costs
- Increases warehouse safety
- Can be retrofit to existing rack
- Works in selective, drive-in and push-back systems
When looking at the two designs, we easily see the feature differences, but what do those differences mean for your storage systems and warehouse operation? Here’s a basic review of the two systems to help you determine which might be the right pallet rack design for your storage and fulfillment needs.
Cantilever Frame Designs:
Offset/Cant Leg Frame – Features include a sharply recessed front post at a 90° angle to the rear post. The height and depth of the offset is varied depending on system application. Unique to this design is the ability to set the offset to sit as low as 6” off the floor to avoid outriggers and still allow for an additional lower beam/pallet level. The 90° offset provides an easier visual for forklift drivers to gauge clearance for outriggers.
There are a couple drawbacks to the cant leg – it can be more expensive to engineer due to the difficulty of managing the transfer of forces from the frame to the floor. For this same reason, the extent of the recess is typically limited to a little more than half the depth of the frame.
Slope Leg – Easily identified by the gentle slope of the front column toward the rear column of the frame. The angle of the slope is based upon rack dimensions and capacity requirements, but can extend as far back as the base of the rear column. Slope leg frames are often used in drive-in/drive-through pallet racking applications to mitigate the fork truck abuse encountered as they enter, exit and maneuver around the system. Slope leg columns can even be manufactured to be stronger than traditional straight leg pallet rack uprights while still providing greater forklift vs rack clearance.
Slope leg posts can also serve as rack repair replacement for straight leg posts to allow better fork truck/aisle clearance with existing pallet racking systems. Apex repair technicians can complete the pallet rack post repair without having to unload the entire pallet rack, saving you expensive system downtime losses. Depending on your repair/replacement needs, slope leg repair kits can be either bolted or welded to the existing frame.
A design limitation with the slope frame is that the lowest beam elevation must be higher than the start of the slope on the frame. It can be more difficult for the forklift driver to gauge the rack clearance vs. the cant leg due to the gradual slope.
A third option, the Raised I-Beam base design elevates the product off the floor and still provides additional clearance for the outriggers of the reach truck by removing the front column. Pros and cons of this system design are outlined below:
Raised I-Beam Design Pros
- Continuous load bearing pallet support
- Pallet supports attached to all three beams for additional abuse resistance in the horizontal direction
- Standard rack components for everything above the base
- Bottom beam can be removed for storage on the floor
Raised I-Beam Design Cons
- Monopost / frame design is limited to double-deep application
- Floor-loading is higher than stacked I-Beam base
- Interior beam is five-inches tall, so there is a loss of 1” of vertical clearance on each level
- Large surface area at the base to capture trash and debris
If you’re interested in learning more about cantilever frame designs for your warehouse storage systems, give our pallet racking design experts a call today.