Palletizing and depalletizing rates 2

[Aemon]

I have a problem and need some help.

My customer has several sizes of cases, ranging in size and weight. The sizes range form about 12" x 16" x 8" and 20 pounds up to 18" x 32" x 12" and 100 pounds.

I have an idea to line up the pallets along a conveyor line and off stack the pallets by batch pick and run the full cases through a sortation system. As long as a person can off stack a case at a rate of 1 case per 11.5 seconds, this system concept seems to make financial sense. The pickers will be picking from most every pallet, and they will be picking multiple cases from each skid. The vast majority of the cases are the lighter cases. The travel time form skid to skid will only be a few seconds because the pallets will only be 4 seconds apart.

Is there some standard I can use to validate these rates? I know I can do a simulated time study to determine if this is accurate, but would like to get past the tentative "I am interested in pursueing this" phase before I do that.

So can any one help me out with this?

Best regards,
Aemon from Texas

 

[BillPSU]

There are several variables which will impact your times. Moving a waist height case to a waist height conveyor is a sinch but picking a case at 6' height or off the floor is a different story. How high is the stack and especially the 30-100 pound containers. Is the same person going to do this on a continuous basis all day? Environment, what is it? Is it air-conditioned if not what is the ambient range? What is the mix of containers? 95% over 50 pounds.

Variables affecting any time standards are skill, effort,environment, personal, fatigue and delay. This job doesn't require a lot of skill but proper techniques in lifting will be mandatory. Detrashing will impact your time. Are the pallets shrink wrapped? Where do they dispose of the trash? Is scanning required? Is there enough room to walk around the pallet or do you have to drag the boxes from the rear to the front? Do the containers have handholds? Who moves the pallets to the unload position? Who disposes of the pallet?

I've asked more questions than gave answers but its the devil in the details.

Lift table can eleviate the lifting problems however cost becomes a bigger issue. Segregrating heavy from light containers would limit the number of lift tables required.

 

[Aemon]

Bill,

The pallets are at ground level, so the case range will be fom about 6" top of pallet ot 58" top of highest case tier.

I would say about 75% of the product is less than 30 pounds per case.

The environment is freezer cooler.

Yes, I plan on rotating workers and evenly distributing the large heavy cases by volume evenly amoungst the pick zones.

I am considering pick return for the empty pallets, so handling them is not an issue.

Yes the containers have hand holds and are easily grabbed.

No, the pallets are in racking, so it is a front pick only.

I may consider running a seperate trash line, I had not considered that a problem, but perhaps the pick return system will have the clearance for the film to be stashed in the pallet to be dealt with later.

Pallet flow rack will take care of the moving the pallet to the pick position.

I think this covers the essential questions.... so tell me what you think.

Best regards, and thanks for your interest.

Aemon from Texas

 

[BillPSU]

Aemon

I think your plan is very workable. The workers will be wearing some cold protection but causing some extra effort from the bulk of the garment and additional weight but the cool temperatures will allow good heat disipation.

Take a look at the gloves being used. Soft rubber gloves with a lining will improve grip and provide a temperature barrier.

The 11.5 seconds handling time is possible but to verify the time go to the customer's plant and watch them unload several of their pallets. Don't do a time study just use a wrist watch and watch them work from a distance or have the customer verify the time. Another way is to mockup the setup at your facility.

Good Luck in your project.

Bill from Kansas