Unit 3 Storage This unit is designed to give you an introduction to the concept of storage as it relates to the logistical handling of materials. Well-planned and calculated storage requirements are time, motion, and money savers.

Warehousing Warehouses organize and protect materials until they are needed elsewhere Most products arrive at the warehouse as a pallet load Occasionally, less than full pallet or container loads – Cases, cartons, individual items

Definitions Size – Size matters when dealing with individual items – Pallets, containers, and cartons have fairly standard dimensions Standard pallet is 40” x 48” Volume – How much of any one item is being stored – How much of is retrieved for shipment This is throughput or velocity

Definitions cont’d Density – Storing large quantities as pallet loads or in similar large containers – High density storage = smaller warehouses and less aisle space – The greater the volume the greater the desired density – Density can work against you if frequent access to loads is important due to throughput

Pallets vs. Cases – The items being moved at one time dictates the kind of case storage equipment that is most suitable – Large demand calls for pallet load retrieval and shipping

Key Issues in Palletizing Items typically arrive as pallet loads Based on demand, some items may need to be shipped as cases or single items. – A certain number of pallets may be broken apart to provide access to cases or individual items. Pallets that are broken apart are moved from the “full” pallet and placed in case storage equipment Some pallets arrive as a mixed pallet load – Not all the same items on a pallet

Key Issues in Palletizing cont’d Remember – Volume or quantity dictates whether you deal with pallets, cases/cartons, or individual items – Quantity of any one load influences density, but volume per unit of time (throughput) can remove the importance of density. Pallet Carton Case Individual Item

Three key issues in dealing with storage are  Mass, measurement, and space  Volume, density, and size  Depth, containment, and process  Weight, configuration, and delivery method

3.1 Warehouse Design The first step in planning the storage function is to calculate size – Size matters, in regards to individual items – Area = length x width 1 ft 2 = 144 in 2 – Volume = length x width x height 1 ft 3 = 1728 in 3 – Standard pallet is 40” x 48”

Cont’d The second step in planning the storage function is to calculate weight – Calculating weight includes the weight of the materials and the weight of the pallet Remember: – Materials being stored must be measured and weighed before any further planning for warehouse storage space is completed

Determining Volume of Materials Estimate as closely as possible the number or quantity of materials for storage This should address peak volume that is predicted to be handled This will determine the amount of floor space and ceiling height needed for the warehouse

SKU Stock Keeping Unit Each unique type of item in the warehouse is issued a unique SKU number or designation code – DVD players get one SKU – VCR players get another SKU The SKU is NOT the actual amount of any one item in the warehouse, but instead is a designation of the item(s) that is to be inventoried and stored

Space Usage Space usage is crucial to the profitability of any warehouse – The space usage must be efficient Aisle placement plays a crucial role in space usage

Aisle Placement Position them in a manner that is friendly to the equipment used Must provide safe travel paths for movement of material and personnel Efficiency is tied directly to worker time – Time is Money Movement and storage of materials must be as least time consuming as possible Must be wide enough to accommodate equipment maneuvering and turning

Helpful Hints Area = length x width Volume = length x width x height 1 ft 2 = 144 inches 2 1 ft 3 = 1728 inches 3

3.2 Block (Floor) Stacking

3.3 Storage Rack Block stacking is not the choice for all materials – Some materials cannot be stored on the floor The logical alternative is the storage rack – You can see the storage rack in use at places like Lowe’s Home Depot Sam’s Club

Storage Rack Construction Fabricated from – Formed steel – Structural steel Size and gauge of steel is determined by capacity needed

Types of Rack Selective Pallet Rack Drive Through Storage Rack Drive In Rack Flow Through Rack Push Back Rack Cantilever Rack Mobile Sliding Rack

Selective Pallet Rack Upright Beam (Post) Load Supporting Beam

Selective Pallet Rack Most popular type Material is placed in opening in rack and supported by – Load-supporting beams Back to Back Arrangement – Flue between the two rack sections Pallet overhang Fire protection means Single Row Arrangement – Placed against walls to utilize floor space efficiently

Selective Pallet Rack cont’d Back to Back Selective Pallet Rack Single Row Selective Pallet Rack

Selective Pallet Rack cont’d Configuration – Single row is the most flexible Pallets can be stored, retrieved, or picked without handling other pallets Can be used for the following types of storage – Standard: single deep using counterbalanced truck – Narrow-Aisle: storage using a narrow aisle truck – Deep- Reach: greater than single deep

Selective Pallet Rack cont’d Sizing – Sized when ordered – Based on dimensions and weight of materials to be stored – Loads rest on the front and rear beams – Accommodations must be made for type of lift truck servicing the rack Outriggers on straddle truck

Selective Pallet Rack cont’d Capacity Rating – Do not place too heavy or too large a load on a section of pallet rack – The rack may fail and fall – Damage to rack, other materials, personnel – Capacity is based on strength of components

Selective Pallet Rack cont’d Advantages – Used where there is limited floor space – Provides more effective use of vertical space than block stacking – Allows personnel to see all pallet loads in storage They are hidden behind other pallet loads

Selective Pallet Rack cont’d Pallet rack is safe, but other safeguards can be installed: – Rack Decking – Rack Guarding

Selective Pallet Rack cont’d Rack Decking – Welded wire mesh, perforated steel, or wood – Attached to and overlays beams – Prevents items from falling through – Adds strength to the equipment – Serves as a shelf for cartons/cases and individual items

Selective Pallet Rack Rack Guarding – Protects the bases of rack from collision by lift trucks, pallet jacks, and other equipment – Absorbs the brunt of the collision – Can result in injury to personnel and structural failure of rack – Types Guard rails Corner guards Bollards Post guards

Drive Through Rack

Serves a unique purpose Placed strategically in warehouse where there is a need to move high volumes of palletized materials into and out of storage racks via lift truck and where block stacking is not suitable Lift trucks are driven between the upright beams (posts) Loads must be of similar width Open at both ends, FIFO Form of high density storage

Drive In Rack

Similar to drive through rack except: – Only enter from one side; therefore, – Materials are subject to LIFO – Used for high volume storage just like drive through rack except: Can be placed with one side against wall – Used for storing large number of pallets of same SKU – Can store 5-10 pallets deep

Flow Through Rack Gravity Rollers High End Low End

Flow Through Rack Allows boxes, totes, or pallets to move forward on gravity rollers or skatewheels Materials are loaded on the high end and unloaded on the low end Materials are subject to FIFO Supports highest level of throughput for high density storage

Push Back Rack

Inclined from front to back Pallets are placed on carts in rack Pallets are pushed up the incline by other pallets being loaded on rack Only used for pallet loads, not cartons Materials is subject to LIFO many times the high side is against wall

Remember All these types of rack offer a higher density of storage than selective pallet rack. This resulting density of storage requires fewer access aisles and less floor space

Cantilever Rack Cantilever Arms

Cantilever Rack Used in home improvement warehouses where they store lumber, steel, or other large items Designed to handle materials that are too long or narrow to fit on pallets, in cartons, or on normal racks Loads are supported by cantilever arms extending out from a base section in one or two directions

Mobile Sliding Rack Back and forth movement along rails in floor

Mobile Sliding Rack Rows of storage rack that are affixed to a set of rails embedded in the floor Only one aisle is needed because the racks move side to side, which in turn moves the aisle Often used for carton storage Often used for document archival warehouses Eliminates the need for multiple aisles Used when access and turnover is low

What is it?

What is it? Is it FIFO or LIFO?

What is it?

What is it? Is it FIFO or LIFO?

What is it?

What is it? Is it FIFO or LIFO?