BEST PRACTICES: Space utilization

Warehouse and distribution center managers constantly face the challenge to efficiently utilize space – and therefore reduce costs – while selecting material handling solutions that are specific to their applications and needs

12/15/2010


Warehouse and distribution center managers constantly face the challenge to efficiently utilize space – and therefore reduce costs – while selecting material handling solutions that are specific to their applications and needs. Considering the throughput of products at a facility can better help managers understand their warehousing needs, helping to uncover solutions that combine material handling products and storage solutions to enhance productivity and drive down costs.

Lift truck, rack choices impact storage density

Effective warehouse space design must accommodate increasing numbers of stock keeping units (SKUs) while increasing cube utilization. To achieve this task, there are many types of lift trucks in various configurations and racks to consider, as each provides a specific storage function. For example, rack options include selective, deep-reach, drive-in or push-back rack.

The type of lift truck also is critical to efficiently utilizing space. Sit-down counterbalanced trucks require a wide (10-foot) aisle to retrieve materials stored in rack. Reach trucks require a narrow (8-foot aisle), and turret trucks require a very narrow aisle (5½-feet wide). The trucks that work within narrower aisles allow for more pallet storage and less space devoted to the aisle. In addition to using the horizontal space more effectively, narrow aisle trucks can lift higher, better utilizing available vertical space.

Chart 1 shows the number of pallet levels accommodated and the square feet required for each pallet stored using different types of lift trucks.

As an example, when comparing four levels of pallet storage, the reach truck enables storage of more than 20% more pallets in the same space as the sit-down counterbalanced lift truck. The turret trucks increase storage by more than 30% compared with the counterbalanced truck. When the turret truck is used for nine levels of pallet storage, it increases storage density 70% more than the sit-down counterbalanced truck.

One size doesn’t fit all

Some warehouses employ multiple methods of storage, such as various types of racking or mezzanines. Combining different types of storage systems is important in maximizing warehouse space utilization. However, the storage mediums should be selected based on the movement of inventory.

The Pareto principle states that 80% of the activity in a warehouse comes from 20% of the items, and these items are the fast-movers within the warehouse. The next 15% of the activity comes from 30% of the items, which are the medium-movers. Finally, 5% of warehouse activity comes from 50% of the items, which are the slow-movers.

By separating the fast-, medium- and slow-moving products within a warehouse, throughput can be increased by optimizing access to the fastest-moving products. Easier access to the products that generate the most warehouse activity reduces time spent traveling within a warehouse, enabling more time to be spent handling products.

Fast-movers typically are stored in bulk storage and wide-aisle selective pallet rack. For companies using reach trucks, fast-moving products can be stored in narrow aisles. Medium-movers are often best stored in narrow aisles that are equipped with selective pallet rack, carton-flow rack or carousels. Slow-moving products generally are stored in very narrow aisles and utilize turret trucks, carousels and shelving.

Seek opportunities for storage

Consulting with a material handling expert can help companies identify additional ways to increase pallet storage capacity or enhance warehouse design efficiency. For example, there may be an area above cross aisles that can be converted to storage space. Or, it may be possible to add racking to the area above dock doors. By examining opportunities to expand vertically into available space, warehouse managers can utilize the existing area more efficiently within a facility.

Understanding the number of SKUs and the number of pallets of each SKU is essential to optimizing warehouse design for ideal space utilization. In addition, warehouse managers should evaluate the movement of each of the SKUs. This information will drive decisions regarding material handling and storage systems, including rack height and required aisle widths.

By properly configuring warehouse space and material handling products to meet material handling and storage needs, facility managers can take steps to meet their ultimate challenge to drive down overall warehousing costs and enhance productivity.

- Susan Comfort is product manager of narrow aisle products, The Raymond Corporation

Return to BEST PRACTICES: Finding the way forward



Top Plant
The Top Plant program honors outstanding manufacturing facilities in North America.
Product of the Year
The Product of the Year program recognizes products newly released in the manufacturing industries.
System Integrator of the Year
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
June 2018
2018 Lubrication Guide, Motor and maintenance management, Control system migration
May 2018
Electrical standards, robots and Lean manufacturing, and how an aluminum packaging plant is helping community growth.
April 2018
2017 Product of the Year winners, retrofitting a press, IMTS and Hannover Messe preview, natural refrigerants, testing steam traps
June 2018
Machine learning, produced water benefits, programming cavity pumps
April 2018
ROVs, rigs, and the real time; wellsite valve manifolds; AI on a chip; analytics use for pipelines
February 2018
Focus on power systems, process safety, electrical and power systems, edge computing in the oil & gas industry
Spring 2018
Burners for heat-treating furnaces, CHP, dryers, gas humidification, and more
April 2018
Implementing a DCS, stepper motors, intelligent motion control, remote monitoring of irrigation systems
February 2018
Setting internal automation standards

Annual Salary Survey

After two years of economic concerns, manufacturing leaders once again have homed in on the single biggest issue facing their operations:

It's the workers—or more specifically, the lack of workers.

The 2017 Plant Engineering Salary Survey looks at not just what plant managers make, but what they think. As they look across their plants today, plant managers say they don’t have the operational depth to take on the new technologies and new challenges of global manufacturing.

Read more: 2017 Salary Survey

The Maintenance and Reliability Coach's blog
Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
One Voice for Manufacturing
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Maintenance and Reliability Professionals Blog
The Society for Maintenance and Reliability Professionals an organization devoted...
Machine Safety
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
Research Analyst Blog
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Marshall on Maintenance
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
Lachance on CMMS
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.
Electrical Safety Update
This digital report explains how plant engineers need to take greater care when it comes to electrical safety incidents on the plant floor.
Maintenance & Safety
The maintenance journey has been a long, slow trek for most manufacturers and has gone from preventive maintenance to predictive maintenance.
IIoT: Machines, Equipment, & Asset Management
Articles in this digital report highlight technologies that enable Industrial Internet of Things, IIoT-related products and strategies.
Randy Steele
Maintenance Manager; California Oils Corp.
Matthew J. Woo, PE, RCDD, LEED AP BD+C
Associate, Electrical Engineering; Wood Harbinger
Randy Oliver
Control Systems Engineer; Robert Bosch Corp.
Data Centers: Impacts of Climate and Cooling Technology
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
Safety First: Arc Flash 101
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
Critical Power: Hospital Electrical Systems
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me