Optimal Lane Depth Exercise

Exercise. This exercise is based on slide presentation SP$6($Pallets$.$ Floor Storage$).$ Be sure to study the respective slides

of the presentation first. You will have two attempts for this exercise online. Enter your best estimates first, then check

if you answers are correct. If some answers you entered are wrong, analyze those questions using question feedback,

study the examples in the presentation and do it again. Each question is worth $3$ points.

You receive stackable product for storage on $48$ by $48-$inch pallets without product overhang. You can stack the

product $4$ tiers high and need to keep up to $200$ pallets$*$ of this product in your warehouse. You use wide, $16-$ft aisles

in your warehouse for an easy counterbalance lift truck operation. If as a result of calculations, you get fractions of

lanes or pallets, round them up or down to the nearest integer numbers using standard rounding rules.

$1.$ We will use the OLD formula in SP$6($rather than in the Frazelle book$).$ Just to make sure you understand the

conversion between different units, let$$s convert everything into feet and split the formula calculation into steps.

Tiers are tiers and should not be converted into anything. First, calculate the product in the denominator.

$2.$ Now calculate the product in the numerator, divide it by the denominator you found in item $1$ and find the square

root of the result. Thus, you have calculated the OLD using the whole formula. Notice that strictly speaking the

answer is unitless, but this is a heuristic formula anyway, so we will say that the answer is the number of pallets on

the floor in one lane, i$.$e$.$ lane depth expressed in pallets.

$3.$ How many pallets will there be in a full lane? The pallets will be stacked in the lanes as high as possible, so please

find how many pallets one lane will contain taking into consideration both the lane depth you calculated in item $2$

and the number of allowed tiers. The answer is in pallets.

$4.$ How many lanes will you need for this product?

$5.$ This formula works great when you receive a new product and place it in the empty space in your warehouse.

However, over time, as you receive and ship loads, you will inevitably get some honeycombing, particularly if you are

trying to work with a loose FIFO rather than LIFO. Suppose you want to estimate the effects of honeycombing. If it

has a factor of $80\%,$ i$.$e$.$ honeycombing reduces your actual storage space usage from $100\%$ to $80\%,$ how many pallets

of stock will you actually keep in the space you originally allocated for this product based on OLD in items $24?$

$6.$ Taken into account the honeycombing factor in item $5,$ how many lanes will you need to keep for this product on

the average, if you have $150$ pallet loads on hand on the average and use the original OLD in item $2?$

$7.$ You have been told about a safety stock increase for this product. So you will be required to accommodate up to

$240$ pallets. What will the new OLD be$,$ disregarding any honeycombing?

A practical learning point: What do you do if you have leftover pallets on hand not enough to form a full lane? If you

have sufficient space, then start a new lane anyway. You will use the space somewhat less than optimally, but the

storage will be well organized. You may want to direct your personnel to prioritize that lane for picking pallets for

shipping to free up the whole lane as soon as practically possible.

If you are short on space, and a new lane is definitely the luxury you cannot afford, you have two options. One, use a

shared $($mixed lane$)$ with the next product. Your WMS must be able to track it$,$ and$/$or you may want to mark this lane

with both product names, codes, etc. Two, create a separate zone in the warehouse for small number of leftover

pallets of different products. It may look like lanes of lesser depth that still use efficiently the warehouse space, given

its layout. Again, this zone must be so identified physically and in the WMS$,$ and your process must call for picking

from that location first. You may also have different rules about sending or not sending product into that zone based

on its velocity $($fast mover vs$.$ slow mover$).$

$*$ Note that the word $$pallets$$ here is used to denote loads on pallets, not empties; this is common in warehousing.