The document discusses how operations engineering can optimize tilt tray sorters to help retailers address the challenges of omni-channel distribution. Through analyzing workflow and identifying bottlenecks, operations engineering can reconfigure sorter software to improve throughput and fulfillment without needing new equipment. By leveraging data modeling and simulations, operations engineering provides automated decision-making that allows the sorter and warehouse to self-optimize for maximum efficiency. Retailers can breathe new life into legacy tilt tray sorters through operations engineering instead of replacing expensive equipment.

1. WHITE PAPER
Tilt Tray Sorter Optimization:
How Operations Engineering Can Breathe
New Life into Your Depreciating Equipment

2. The way consumers interact with brands has changed: no longer are customers satisfied with a single
channel by which to obtain their goods. Instead, customers are demanding options. They want new and
diverse methods to interact with retailers. Whether it is through in-store purchases, eCommerce, or
anywhere in between, retailers are left scrambling to provide customers with options to meet growing
demands. These new demands, and the subsequent logistical challenges brought on by them, have
become known as omni-channel distribution.
These changes have altered the landscape of supply chain. In order to remain competitive, retailers must
attack these complex logistical challenges head on. They must invest in solutions that provide rapid,
accurate, and dependable order fulfillment regardless of sales channels or order profiles. But how can these
challenges be addressed without the expense of costly capital expenditure?
Tilt Tray Sorter Optimization:
How Operations Engineering Can Breathe
New Life into Your Depreciating Equipment
Tilt Tray Sorter Optimization:
How Operations Engineering Can Breathe New Life into Your Depreciating Equipment1
Reddwerks Corporation
1122 S. Capital of Texas Highway, Suite 150 Office: 512.597.6810 Fax: 512.597.6820 www.reddwerks.com

3. Omni-channel distribution has brought with it the need for advanced technology. This is particularly true in
the last mile of order-fulfillment. Modern retailers no longer simply push out a steady number of forecasted
orders to their supply chain vendors. Instead, they must respond to variably sized orders being pulled
through a multitude of channels. The modern retail distribution center must simultaneously process and
fulfill both store and direct-to-consumer orders, and they need to be able to achieve this utilizing the same
inventory.
As competitors and customers continue to motivate retailers to transition to this new methodology, retailers
must determine how their depreciating equipment fits into their overall operation. Facilitating the order
fulfillment of multiple and changing order profiles across numerous sales channels can seem like a costly
proposition. With a significant amount of capital already spent on infrastructure, and the demands of
omni-channel ever changing, few distributors want to sink more money into material handling equipment
(MHE).
Tilt tray sorters exemplify this problem. Tilt tray sorters, like most unit sorter equipment (cross-belt, Bombay,
etc.), automate the put process involved in batch pick-to-put. When correctly implemented, they eliminate
the need for the put-and-pass required in most manual batch pick-to-put systems, substantially increasing
the number of orders that can be included in the put batches. This not only simplifies the operation but also
significantly reduces put and pick labor.
Unfortunately, many retailers have legacy tilt tray sorters running sub-optimized software in their
warehouses. This gravely impacts the entire order-fulfillment operation in a facility. Some distributors have
sought new MHE to solve this problem. It is not uncommon to see distributors purchase expensive pre-sort
buffers to help picking productivity issues brought on by legacy sorters. Still, most of these purchases only
provide a stopgap for a larger problem.
Then why not simply replace the sorter?
Omni-Channel and the Problem of
Depreciating Hardware
Reddwerks Corporation
1122 S. Capital of Texas Highway, Suite 150 Office: 512.597.6810 Fax: 512.597.6820 www.reddwerks.com
2
Tilt Tray Sorter Optimization:
How Operations Engineering Can Breathe New Life into Your Depreciating Equipment

4. There are several strong reasons for retaining existing tilt tray sorters. Beyond avoiding the disruption and
cost that a sorter replacement would cause to an outbound operation, leveraging the proper technology
can breathe new life into an otherwise less-than-optimal component of the order-fulfillment process.
Through the use of operations engineering, tilt tray sorters can be transformed from a choke point into an
asset, increasing ROI and operational agility without the added capital expenses of new or additional MHE.
Legacy Tilt Tray Sorters
In the early 1980s, U.S.-based retailers began to move away from labor-intensive operations involving split
case product flows. As volumes increased and service-level agreements tightened, businesses realized
that moving products manually, or even with mobile equipment, was not a sustainable practice. It became
necessary to find a new way to reduce handling costs—one that would increase the bottom line.
These retailers turned to an emerging breed of conveyor and sortation equipment capable of taking over
most of the human-executed movements and performing them with a speed and accuracy that would
have proven too costly with manual labor. Among the automated sorting technologies available, the tilt tray
sorter stood out as a premier option for retailers, providing an efficient and effective solution to address one
of their chief challenges: the shipping dock.
At the time, retailers’ primary focus was on keeping their network of stores stocked with current
inventories. Products were not shipped based on real-time needs, but rather on forecasted demand. This
model was generally known as store replenishment. Tilt tray sorters proved an efficient tool for this push
style of operation.
Over time, increasingly complicated demands brought about new solutions. By the late 90s, PC-based
controller software provided distributors the capability for faster order processing. In addition, shoe sorters
became the industry standard for most greenfield projects, due to their versatility.
Reddwerks Corporation
1122 S. Capital of Texas Highway, Suite 150 Office: 512.597.6810 Fax: 512.597.6820 www.reddwerks.com
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Tilt Tray Sorter Optimization:
How Operations Engineering Can Breathe New Life into Your Depreciating Equipment

5. The Use of Operations Engineering
Still, many retailers have retained their legacy tilt tray sorters in order to mitigate the disruption and cost of
replacing an expensive piece of MHE. For others, tilt tray sorters remain the sorter of choice for their
durability and capacity to handle specific types of merchandise, such as apparel and even poly-bags.
Regardless of the reasons, all these distributors face the same problem: having a sub-optimized piece of
MHE creating a choke point in their order-fulfillment process.
Operations engineering provides a solution for these distributors. By leveraging analysis, simulation and
event-driven software via an operations engineering study, warehouses can re-calibrate a sorter, changing it
from a choke point into an asset.
Order-fulfillment automation, for a tilt tray sorter or any other technology in a warehouse, can only be
effectively optimized when analyzed within the context of the larger chain of processes occurring inside a
facility. Operations engineering provides the insight and execution needed to achieve this form of
optimization.
Operations engineering is the systematic analysis of an existing or proposed warehouse to locate and cure
workflow inefficiencies as well as identify MHE utilization bottlenecks. While most distribution centers share
commonalities, an operations engineering study is premised on the idea that each facility has unique
physical and logical constraints. The purpose of the study is to find methods within these constraints to
meet a distributor’s quantifiable goals and then to configure and calibrate software to implement this
solution in real production.
A successful operations engineering effort provides distributors with an engine that can compile and crunch
data in real-time from the separate islands operating inside a warehouse. This gives distributors insight into
what is happening inside their warehouse. But, more importantly, it creates an automated decision maker
capable of determining the best action to take at the conclusion of each event occurring inside the
warehouse. The result is a self-automating warehouse that plans and adjusts throughout the day, providing
maximum throughput at the lowest possible cost.
Reddwerks Corporation
1122 S. Capital of Texas Highway, Suite 150 Office: 512.597.6810 Fax: 512.597.6820 www.reddwerks.com
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Tilt Tray Sorter Optimization:
How Operations Engineering Can Breathe New Life into Your Depreciating Equipment

6. Effectively Deploying Operations
Engineering for Tilt Tray Sorters
Developing these types of engines requires the operations engineering team to leverage advanced
computational methods, such as data modeling and time-based simulations. These techniques help the
team to identify every decision point inside the warehouse as well the constraints within the existing
infrastructure and systems. The resulting decision algorithms are refined and then incorporated directly into
a software module. Typically, this would be a fully integrated solution, such as warehouse execution
software (WES).
While the operations engineering method does take an investment on the part of the distributor, it provides
a clear business case and a precise ROI. In addition, it leads to successful solutions based on real data
modeling, minimizes the necessity for costly rework and unexpected problems down the line.
An effective operations engineering approach to sorter optimization begins with the premise that not all tilt
tray operations are the same. Even in warehouses with similar SKUs, order profiles, and material and labor
frameworks, there are differences in the way the facility leverages its MHE. This could be a facility-wide
goal, pain point, or any of a variety of factors. It is these differences that go into determining how the MHE
can most effectively be used in a specific warehouse.
An effective sorter optimization plan attempts to achieve two related outcomes:
• Maximize loads through MHE (without creating bottlenecks)
• Optimize labor usage throughout the warehouse
Both of these outcomes are ideal for any process or technology inside the four walls of your warehouse.
However, they are even more critical when talking about a sorter. The sorter, in most situations, sits at the
focal point where inefficiencies manifest. Waves that are too big for the sorter, or are too inconsistent across
the day, create bottlenecks. Similarly, inefficient distribution of orders among the chutes can quickly throttle
an operation.
Reddwerks Corporation
1122 S. Capital of Texas Highway, Suite 150 Office: 512.597.6810 Fax: 512.597.6820 www.reddwerks.com
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Tilt Tray Sorter Optimization:
How Operations Engineering Can Breathe New Life into Your Depreciating Equipment

7. These are only a few examples of how the sorter can choke work across the facility. The reality is that an
order fulfillment system works as an interconnected system, with the sorter acting as the brake. Effectively
optimizing your tilt tray sorter through operations engineering can limit, if not remove, the effect that brake
has on an entire warehouse.
Most operating tilt tray sorters have a fixed number of orders allocated to each chute. Orders are then
sorted and filled based on the current capacity of that chute. In most cases, the legacy software systems
controlling these sorters work in static waves. Wave orders are hard allocated to chutes before the wave
starts sorting. A wave cannot start until the previous wave is completed. In a sense, the mechanical
limitations of the sorter dictates the flow of orders through the entire warehouse based on the number of
chutes and the speed of labor at the chutes. Upstream, pickers can only select as quickly as their
counterparts at the sorter can empty chutes. Conversely, non-optimized chute feeding causes sorter labor
to scramble, trying to empty out their chute downstream, while upstream labor is idle, waiting for the next
wave to be released.
In these systems, sortation rates can be very high mid-wave, with productivity drastically dropping during
wave transitions. Lingering items at the end of waves have a profound negative impact on facility
operations, to the point that sometimes the whole facility is stopped waiting for a few stragglers to
complete the wave.
A skilled operations engineer will look both upstream and downstream of the tilt tray sorter when
determining how to best optimize the equipment so this doesn’t happen. This means looking at all aspects,
from balancing and maximizing order waves across the facility, to producing a throughput that eliminates
idle labor, lengthy footpaths, and poor chute utilization.
Reddwerks Corporation
1122 S. Capital of Texas Highway, Suite 150 Office: 512.597.6810 Fax: 512.597.6820 www.reddwerks.com
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Tilt Tray Sorter Optimization:
How Operations Engineering Can Breathe New Life into Your Depreciating Equipment

8. 1 Work Allocation
2 Chute Balancing
3 Chute Cubing
When developed and implemented correctly, operations engineering creates calibrated algorithms that can
dramatically increase the effectiveness of your tilt tray sorting operations. This can improve the overall
agility of a DC’s operation, prepping a facility to meet the challenges of omni-channel now and in the future.
Whether you believe in a wave-based approach that favors reconciliation, or a waveless approach that
favors dynamic continuous processing, the first step is to create balance throughout the day. This will
prevent backups or bottlenecks at important areas such as the sorter, and ensure that work is maintained
steadily for MHE and for labor.
Traditional usage of tilt tray sorters relies on filling the chutes with the least amount of orders, which can
often lead to chute imbalances across a wave. The result is that much of the labor may be idle as they wait
for one chute to be completed before the next wave can be released. Chute balancing looks at the
number of chutes and packers, and disseminates workloads across each chute accordingly.
Tilt tray sorters often do not see the size of the unit being sorted into chutes. Chute cubing looks at the
volume of orders and number of chutes, and fills chutes based on overall volume, not on number of units.
This allows for larger waves, greater sorting capacity, and increased throughput.
An example of an effective three-step path towards leveraging operations engineering in your tilt tray sorter
might look something like the following:
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1122 S. Capital of Texas Highway, Suite 150 Office: 512.597.6810 Fax: 512.597.6820 www.reddwerks.com
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Tilt Tray Sorter Optimization:
How Operations Engineering Can Breathe New Life into Your Depreciating Equipment

9. Reddwerks Warehouse Execution Software, powered by Distribution Science®, combines intelligent,
decision-making engines developed by our in-house operations engineering team with the modularity of our
state-of-the-art software.
Our solution features a robust and stable architecture that allows a seamless deployment of operations
engineering algorithms for tilt tray optimization as well as all other conveyable and non-conveyable needs
inside the four walls of a warehouse.
Our system integrates easily with any WMS/ERP, and can be deployed in any existing or proposed
warehouse to give distributors the operational agility they need to operate an omni-channel strategy.
Whether you are looking to optimize your tilt tray sorter, improve labor efficiency, increase other material
handling equipment utilization, or extend the capabilities of your existing WMS or ERP, Reddwerks
Warehouse Execution Software can help take your distribution facility to the next level.
The Reddwerks Solution
At Reddwerks, we view distribution as a single, interconnected system. Our Warehouse Execution
Software, powered by Distribution Science®
, combines execution with analysis by synchronizing the
discrete processes inside the four walls of a warehouse to create a real-time decision engine, automating
labor and work. Our software provides customers the operational agility they need to handle the demands
of an omni-channel environment.
About Reddwerks
Reddwerks Corporation
1122 S. Capital of Texas Highway, Suite 150 Office: 512.597.6810 Fax: 512.597.6820 www.reddwerks.com
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Tilt Tray Sorter Optimization:
How Operations Engineering Can Breathe New Life into Your Depreciating Equipment