All I Want for Christmas is an Empty Box?

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Empty boxes on conveyor
I was recently talking with a client who wants to improve productivity by increasing the efficiency of his facility’s picking operation. As we talked, I learned he was thinking about going to a pick to pack methodology, so I asked him how he was going to get the boxes to his operators.

He was leaning toward putting in a few carton erectors to build the various box sizes he needed for his orders, so I mentioned to him that carton erectors only built the boxes; they wouldn’t get them to the operators. He replied, “that’s the easy part: getting the empty boxes to the operators.” I knew right then that this guy had never before conveyed empty boxes.

Most people are just like him and think that because the boxes are empty, it should be easy. In my 23 years of experience, I have found empty boxes to be some of the most troublesome items to convey. I know they are empty, so they won’t stall out conveyor rollers; however, being empty and light creates its own set of problems.

The Problems with Conveying Empty Boxes

Problem 1: Once a box is erected it does not have a flat bottom. This uneven bottom will cause the box to track all over the roller conveyor and lean and possibly fall over on a belt conveyor. This uneven box bottom will also cause problems when you try to transfer off the main transportation line in the picking area. I know a lot of box erector companies say their machines make flat bottom boxes, however no companies will put that in writing with a money back guarantee either. The smaller the box and the narrower the box the worse the problem. Also, the bigger the variance from the largest box to the smallest box, the greater chance for problems. You can solve this by sizing the conveyor and guardrail so the box cannot fall over.

Problem 2: Friction between an empty box and a conveyor guard rail causes system jams. There can be a lot of friction between a box and the guard rail on a conveyor. When a box is empty, this friction often keeps it from being conveyed on either belting or conveyor rollers. This can lead to unwanted jams and backups in your conveyor system. You can solve this by using guard rail with the least amount of surface area touching the empty box. I recommend something that is round like a piece of light gauge metal tubing.

Problem 3: Empty boxes running on high-speed conveyor often tip over. Empty boxes on zero pressure accumulation conveyor can also be a problem if you run the conveyor with the empty boxes at a higher speed such as 120 fpm or higher. This higher speed with all the stopping and starting will cause a lot of the boxes to tip over or slide on the rollers and go past the accumulation zone sensor. When that happens, two boxes end up in the same accumulation zone.

The situations listed above are with boxes used for shipping; however, most distribution systems also have a trash conveyor system to move empty boxes as well. Most trash conveyors consist of a very wide belt conveyor with high guards to keep the empty boxes from falling out. If the trash conveyor consists of just one straight conveyor then you have very little to worry about. However, when you need to snake the conveyor through the building you will find out how tough conveying an empty box can be, especially when you have to make 90 degree turns with trash conveyors.

All of these situations will cause a conveyor system to jam or cause a problem in the picking areas, and again, the smaller and narrower the box, the bigger the problem. If you need to convey empty boxes, remember to:

  1. Size your conveyor and guard rail so boxes cannot fall over.
  2. Use guard rail with the least amount of surface area touching the box.
  3. Keep conveyor speeds a bit lower in areas transporting empty boxes.

I know my children never want to receive empty boxes for Christmas, but their dad knows how to handle them if Santa leaves any.

I have been with Bastian Solutions for over 20 years. During that time, I have been in many different positions including Sales, Engineering, Project Management, Regional Manager and currently, Vice President of Sales, Western US.


  1. Shawn Weber says:

    Last year, I designed a system that was a 4 level pick module that started with a case erector on level one and snaked back and forth and up each level. There were 3 pick n pass units on each level, making up a total of 12 pick n pass units with 2 pick zones per unit( rt and lt) for a total of 24 pick zones and an alpine spiral at the end of each floor to get the boxes up to the next level. A scanner was mounted before each pick n pass to determine if the box had a pick from one of the zones and should divert. Consequently, a empty box could have to travel up 4 levels through 3 alpine spirals to get to the last pick n pass unit on level 4 before it received a pick. Orientation needed to be kept to get consistent scans and to divert properly. I believe only a MDR system could have done this successfully. While there were guiderail solutions needed to help with adequate conveyance, new features on the drive cards from Interroll , namely the acceleration and deceleration features, made it possible to convey and accumulate on the belted zone inclines and spiral curves without tipping or excessive skewing. More end users are going to this type of picking method and features such as this on motorized rollers will be critical in achieving satisfactory conveyance

  2. Calvado says:

    Enjoyed studying this, very good stuff, thankyou . “The fox knows many things, but the hedgehog knows one big thing.” by Archilocus.

  3. Calvado says:

    I have not checked in here for a while as I thought it was getting boring, but the last several posts are good quality so I guess I’ll add you back to my daily bloglist. You deserve it my friend 🙂

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