Issue link: http://palletcentral.uberflip.com/i/685770
palletcentral.com PalletCentral • May-June 2016 39 Common Design Elements: Pallet Specifications: • 48x40 in. • Stringer-class, partial 4-way, reusable, new manufacture • Required Load: 2000 lbs. Lumber: • Species: High Density Eastern Hardwoods (Species Class 1) • Top deck: Seven boards, lead boards 5 ½ in. wide, five internal boards 3 1/2 in. wide • Bottom Deck: Five boards, lead boards 5 1/2 in. wide, three 3 1/2 in. interior boards, • Stringers: Three stringers, 3 1/2 in. high Lifting and Handling: • Racked Across the Length: 44 in. span (2 in. supports) • Racked Across the Width: 36 in. span (2 in. supports) • Forklift: fork tines 36x4x1.5 in. dimensions Differences in Design • Design Aspect "Typical GMA" "Lean GMA" • Stringer Notch Depth 1 ¼ in. 1 in. • Outer Stringer Alignment Flush 1 in. wing • Top Deck Board Thickness 11/16 in. 5/8 in. • Bottom Deck Board Thickness 11/16 in. 5/8 in. • Stringer Thickness 1 ½" in. 1 ¼" in. Analysis • Support Condition "Typical GMA" "Lean GMA" • Racked Across Length 2059 lbs. 2010 lbs. • Racked Across Width 2266 lbs. 2114 lbs. • Forklift From End 2090 lbs. 2360 lbs. • Floor Stacked 1 High 7355 lbs. 7643 lbs. • Floor Stacked 4 High 2724 lbs. 2426 lbs. • Board Footage Used 14.8 bd. ft. 13.7 bd. ft. Discussion The two major design elements in the "Lean GMA" design provide significant strength increases which provide the opportunity to reduce the thickness of pallet components. Since the fork tines in use are slightly thinner (1.5 in.), the notch depth can be reduced as well. The inclusion of a stringer notch provides partial 4-way access to the pallet but introduces two severe defects that significantly reduces the strength of the stringers in the racked across the length condition. The reduction of ¼ in. helps to reduce this negative effect. Secondly, a 1 in. wing is included in the "Lean GMA" design. The wing design reduces the span between stringers, leaving the deckboards better supported by the stringers, which reduces the stress on them. This is particularly important in the racked across the width, forklift, and floor stacking conditions. With the reductions in pallet dimensions, the "Lean GMA" comes in at 1.1 board feet less than the "Typical GMA", which is about a 7% reduction in material usage. PC Game On! Beat this Design Win $100 when you design a better, more innovative pallet than the one highlighted in this feature. Here's the game: submit an alternative 48x40 in. pallet design that meets or exceeds the criteria shown in the specifications outlined (required load of 2000 lbs), using a reduced amount of material (less than 13.7 board feet). Species Class 1 (High Density Eastern Hardwoods) Standard and Better grade and the identical deckboard layout must be used. Use a Flexible Uniformly Distributed Load, Maximum Safe Load Capacity with Medium Load Weight Variability. The winning designer and the schematic will be featured in the July-August edition of PalletCentral – and the engineer will win $100. Submit your design, including your .pdf supporting documents and any additional explanatory language, to Annette Ferri, aferri@palletcentral.com, no later than June 21, 2016. Staff experts will review all submissions to determine the winning design.