Pallet Exam 4

Pallet decks to support box corners

- 2/3 of box compression strength is in corners - unsupported corners compromise strength of box - interlock stress distributes stress to the middle of the panels which reduces in strength - unsupported perimeter reduces strength

Corrugated shipper style

- FEFCO corrugated box standard

Loading Conditions

- Uniformly distributed flexible and rigid loads - Rigid line load - Point load - Discrete load by the actual product

Rolling hoops

- act as reinforcement rings to permit easy handling of the filled drum - most 55 gallon drums have 3 rolling hoops

Plastic drums

- better for acids or corrosive materials than steel drums - lubricants, detergents that easily oxidize - lightweight - reusable - limited compression strength

Using Surface Coefficient of Friction (COF) to stabilize unit loads

- between pallet decks and unit load handling storage and shipping equipment - between layers of packaging - between pallet decks and packaging

Cover style

- bolt ring closure - lever lock ring closure

Packages: primary design criteria

- bulk shipments - containment - parcel shipments - shock and impact resistance - unitized shipments - compression strength

Intermediate bulk containers

- common size is 275 or 330 US gallon - used to store solids or liquid - rigid or flexible - rigid can be non-foldable or foldable construction - discharge could be using gravity or pressure

FIBC sizes

- common size is 35 x 35 x 40 in - common load capacity is 1,500-2,000 lbs - dimensions are highly customizable

Unit load material handling interactions

- compression on packaged product (boxes/pallets and pails/pallets) - vibration dynamic interactions - load bridging and storage racks - surface friction

How do you determine load capacity

- considering safety and functionality - uses deterministic design procedure using safety factors between 2-2.85

Type of Industrial Packages

- corrugated shippers - small handheld containers (returnable plastic container - RPC) - pails - drums - intermediate bulk containers (IBC) - flexible intermediate bulk containers (FIBC) - multiwall paper sacks - bulk containers - crates

Multiwall paper sacks type

- designed with 2-6 paper layer and a plastic layer - closure mechanism: open mouth or valve - closure: sawing or typing (open mount) or robotically (valve)

Drum sizes

- determined by their volume - range from 13 to 110 gallons - most common size is the 55 gallon drum

Pail sizes

- determined by volume - range from 1-12 gallons - most common size is 5 to 5/28 gallon

Metal drums

- extremely durable - handle extreme temperature - reusable

Drums material

- fiber - plastic - metal

Reusable plastic containers (RPCs) advantages

- increased stability due to interlocking design - optimized ventilation - easier cleaning - built in tracking technology - reduced stocking time (CHEP)

How to increase load bridging:

- interlock stacking pattern - tie sheets between layers - larger size packaging - increase friction between packaging - break-away adhesive between packaging - strapping is the best - stretch wrap or shrink wrap

Jerry can

- invented by the Germans in WW2 - common size: 20 liter -english troops lost about 30% of their fuel supplies due to leakage

Fiber drums

- lightweight - easily opened - tamper evident - limited compression strength

Corrugated shippers

- made of strong corrugated 32 ECT B-flute and up - needs to be designed for the intended use

Pails material

- metal pail - plastic pail - fiber pail

Things to Remember (lesson 10):

- not all pallet testing standards provide the same information - the load capacity of a pallet highly dependent on the type of payload - pallet design software has more reliable safety factors - stiffness of the pallet is crucial in automated materials handling

Block or stringer compression test

- only representative to rigid loads - does not bend the top deck - could be as much as 30,000 lbs

Pail types

- open head - tight head

Pallet bending test using fork tine support

- provides "dynamic capacity" - simulates pallet supported by 4 in fork tines - assumes that fork tines go all the way through

Pallet bending test using rack support

- provides "rack capacity" - simulates: load beam and drive-in/drive-through racks

Pallet top or bottom deck bending test

- provides "static capacity" - needs to test both top and bottom decks - clearance between the top and bottom deck is important

Stiff pallets

- reduce compression stress on packaged product during rack and stack storage - reduce amplification of vibration accelerations during shipping - stabilize unit loads - fit automated handling equipment - increase supply chain operational efficiency - reduce packaging spending - move faster in supply chain - important as pallet strength

Pallet bending test using conveyor support

- simulates pallet supported by two track chain conveyors - ISO 8611 - bottom deck bending test simulates this property

Multiwall paper sacks size

- size defined by the dimensions and the weight - weight capacity ranges from 15-150 lbs - dimension ranges: width: 7.5 to 27 in length: 10 to 50 in depth: 3 to 8 in - mostly custom sized

FIBC types

- square or circular bottom - emptying mechanism: skirt, spout, plain - lifting: 2 or 4-point

Drums types

- top style - cover style - drum liner - rolling hoops

Small handheld containers

- totes and reusable plastic containers (RPC) - developed to exchange corrugated containers in closed loop supply chains - made of HDPE or PP - commonly container RFID

Reusable plastic containers (RPCs) disadvantages

- upfront cost - higher weight than corrugated

Bulk containers

- use for mass handling, transport and storage of liquids - most common dimensions: 32 x 30 48 x 40 (grocery) 48 x 45 (automotive)

Minimum COF between pallet and forklift/material handling (ANSI MH1)

0.15

Minimum COF between product and pallet

0.30

Pallet Tests

1. block or stringer compression testing 2. pallet top or bottom deck bending test 3. pallet bending test using RACK support 4. pallet bending test using FORK TINE support 5. pallet bending test using CONVEYOR support

Handheld container types

1. stackable but not nestable - mainly used to store goods in warehouses 2. stackable and nestable 3. collapsible

AIAG RC9

Container performance test guidelines

Support Conditions

Floor Fork tine Rack Sling Conveyor

How do we reduce pallet cost?

Increase load bridging

ISO 8611

Pallets for materials handling - flat pallets (used internationally) - differentiates nominal and maximum working load - uses rigid beams for nominal load testing

Phases that determine load capacity

Phase 1 (safety): 1. conduct a strength test 2. determine the ultimate load 3. divide the ultimate load with the safety factor 4. maximum of the safe load value Phase 2 (functionality): 1. conduct a stiffness test 2. measure the deflection of the pallet under the test load at the end of the creep time 3. compare the deflection to the performance limit 4. adjust the test load to achieve deflection close to the performance limit 5. compare the test load to the maximum safe load 6. the smallest will be your safe load or load capacity

ASTM D 1185

Standard test method for pallets and related structures employed in materials handling and shipping (only used in US) - does not differentiate nominal and maximum working load - uses flexible airbag for comparative testing

Flexible Intermediate bulk container (IBC)

application: - food grade bags - UN bags - multi-trip - chemical bags

Bearing area

area of the top or bottom deck that touches the packages

Effective bearing area

area that effectively supports the product - less than the pallets footprint or the deck coverage - every pallet has an "effective bearing area"

Load bridging

can be used to shift bending stresses away from the center of a unit load in a warehouse rack toward the supports - reduces the bending stress on the pallet and can reduce pallet spending - reduced unit load deformation; reduces pallet and packaging costs when warehouse rack storage is used

Corrugated Box sizes

common footprint was developed to create standard footprint in the retail sector - most popular: 600 mm x 400 mm - fit 5 boxes on a 1,200 mm x 1,000 mm pallet

Compression stress

force divided by area

Corrugated shipper material

liner grades: 26, 33, 42, 69, 90 medium grades: 26, 30, 33, 36, 40 - common corrugated board flutes: A, B, C, E, F - board grade identifies liner medium combination

Load bridging is a function of:

load rigidity - load height - number of layers - number of packages across the pallet - friction between the packages and the packages - package types - package stabilizers support mode pallet stiffness

Handheld container sizes

most common = 600 mm x 400 mm other common sizes: 15 x 12, 24 x 15, 24 x 26 commonly designed to fit 48 x 40 in or 48 x 45 in pallets

Kegs

most commonly used for beer or soda - made of aluminum or steel - size is less than 30 gallon - common size: 15.5 gal, 7.75 gal taping methods: - party pumps - introduces outside air - gas taps - uses 25% CO2 and 75% N - only 10% of beer market

Top style

open - open head is better for solids and thicker liquids - use when frequent extraction of the content occurs tight headed - has secured, non-removable top - used for lower viscosity liquids - 2" and 3/4" bung pole opening on the top

Overview of Pallet/Box Interactions

overhang = 30-42% reduction interlock stacking = 42-50% reduction overhang + interlock = 50-60% reduction unsupported box corners = 30-42% reduction pallet gaps = 8-13% reduction pallet stiffness = ??

Overview of Pallet and Plastic Pail interactions

overhang = 30-44% reduction uneven top load = up to 50% reduction pallet gaps = 13-31% reduction pallet stiffness = up to 40% reduction

Effective bearing area is a function of:

pallet deck stiffness pallet deck coverage package product stiffness support mode

Pails

shipping container with a capacity of 1 to 12 gallons

Vibrations: interactions during shipping

stiffer pallets result in more stable unit loads and better protect certain vibration sensitive products

Drums

straight-sided cylinders that has various capacity ranging from 13 to 110 gallons

Cost breakdown of packaging within a typical unit load

stretch wrap = $1.80 pallet = $8-9 corrugated cases = $45 HDPE 32 oz bottles = $324 3.5 gallon pails = $210

Drum liner

unlined - designed to prevent rusting before filling - 0.1-0.2 mil thin film expoxy-phenolic lining - excellent chemical resistance in pH range 7-9 - used for fatty acids, detergents, foods, organic chemicals, surfactants, water based resins