Forklift aisle spacing in a pallet rack system may be the most misunderstood aspect of the materials handling industry. The answer to the question is not just a flat 12' for a typical sit-down propane lift for example. It is much more complicated than this.
First of all what is the definition of aisle width? Seems simple enough right? I can't tell you how many plan view (from above) drawings I look at that show stated aisle spacing steel to steel. From a draftperson's perspective that is correct. But is it accurate? NO! A typical pallet in the United States is 40" or 42" wide x 48" deep and sits on 42" deep rack. The depth of racking at 42" allows 3" overhang on front and back of rack system. This allows for easier placement of the pallet and places the weight more squarely over the beams. It also means your aisle clearance will be 6" narrower than what was stated on the plan view drawing. Of course, this assumes standard pallet length of 48" and product sitting on the pallet doesn't overhang......a couple of big "ifs". If your pallet rack vendor isn't talking about these things and asking the right questions — buyer be aware! In my career I've seen this mistake countless times. The result is a struggling fork your text here ...
Typical Sit Down Electric or Propane Truck Racking Aisle Spacing - 12'
There are many different types of for trucks to consider that allow different aisle clearances. The following list is based on a standard 48" deep pallets with no product overhang. But first a bit of terminology:
- Fork Truck Length or Head Length - rear of truck to load snack rest (back of forks)
- Load Length = Length of the pallet plus any product overhang
1. Counterbalanced, Sit Down Fork Trucks = Fork Truck Length + Load Length +12" clearance + up to 6" pallet overhang. Normally this is going to be 12' minimum to up to 14'
2 Narrow Aisle Reach Truck - these trucks can be maneuvered to work with very little "play". Meaning if the Truck Length is 104" (typical for 48" pallet) a 9' aisle (108") is adequate for a good driver. 10' is comfortable
3. Double Deep Reach Trucks need a bit more aisle space due to extra mechanics - figure standard 10' or 11' aisles
Double Deep Reach Truck Layout Example
4. Very Narrow Aisle or VNA are typically turret trucks or swing reach trucks. Normally these are guided by wire (embedded in concrete) or angle and used in aisles as narrow as 66". General rule of thumb for aisle width is 12" - 18" wider than the truck's width. Word of warning if you are considering not guiding a narrow aisle truck .....DONT DO IT ! You will be repairing uprights on a weekly or daily basis - they just aren't made to be unguided in my opinion.
Very Narrow Aisle - Wire Guided
Bottom line on aisle width – Gather all your information in front of you to analyze. Be sure the material handling specialists you are working with is well versed in lift equipment, is asking digging questions and can match a layout with pallets / products you will be storing. The wrong layout / lift truck match can be a nightmare for the users – pick times, rack damage etc can be a source of constant pain.
For Help = Call McGee Storage and Handling to set up a free consultation 770-458-4346.Web Site = www.mcgeeatlanta.com
