In today’s logistics and supply chain management, wooden pallets are ubiquitous, the sturdy and reliable workhorses of physical goods distribution. For many of us, they are invisible. Supply chain operators have other things to think about.
Not surprisingly, few pause to consider the design and construction details that go into these essential platforms of modern commerce. In fact, wooden pallets are highly engineered marvels created to move your loads cost-effectively, safely, and with the lowest environmental impact possible.
This article delves into the anatomy of the wooden stringer pallet, focusing on the basic parts of the pallet: the wood deck boards, components, and the fasteners that hold them together. The parts of a wood pallet can be broken down into four main components: the top deck boards, the wooden stringers, the bottom deck boards, and the fasteners. Let’s take a closer look at the anatomy and parts of a wooden stringer pallet.
Top Deck Boards
The top deck boards are the flat pieces of wood that form the top of the pallet. Typically, they are ⅜”, ½”, ⅝” or thicker, and 3 ½” or 5 ½” in width, but all of these dimensions can vary, depending upon the use case and material availability. Thicker material or more dense wood species can help improve pallet performance where needed.
Don’t forget about deck board placement. The corners of the boxes are the strongest part of the box structure and are designed to carry the weight of the box and its contents. Aligning these corners with the deck boards means that the boxes can effectively utilize their structural strength to support the weight of the unit load. Another important deck board design component is the butting of lead or end boards. Pallet lead boards must stand the test of being impacted by forklifts. Butting two 6” lead boards can result in up to a 38% improvement in pallet durability, according to Virginia Tech.
Wood Stringers
Running perpendicular to the deck boards are the wood stringers. These vertical members provide the main support structure for the pallet. Stringers can be likened to the spine of the pallet, distributing the load evenly across the structure and ensuring the pallet’s stability and strength. The standard pallet design usually includes three stringers, but this can be adjusted based on the intended load capacity. Adding more stringers effectively shortens the span between them, thereby reducing top deck deflection under load. Likewise, by using a wing pallet –moving the stringers away from the edge of the load toward the center– you can reduce span and improve pallet strength without adding extra material.
Bottom Deck Boards
The bottom deck boards of a pallet play a crucial role in providing stability and functionality. For wooden pallets used on conveyors or stacked on top of other products, the design of the bottom deck boards is essential.
Wooden stringer pallets typically feature a base where all the deck boards run in the same direction. For example, the GMA pallet has five bottom boards aligned in one direction. For pallets that need to be conveyed smoothly, it’s important to orient the bottom deck boards perpendicular to the rollers. This configuration ensures a smoother ride compared to having the bottom boards run parallel to the rollers, which can lead to a bumpy movement if the rollers are spaced too widely. Additionally, when pallets are stacked, having more bottom deck board coverage helps distribute the weight more evenly, reducing the risk of product damage.
Now, let’s talk about the pallet fasteners, the unsung heroes that hold these components together.
Pallet Fasteners
Pallet fasteners are critical to the structural integrity of the pallet. The choice of nail type, size, stiffness, and application method can significantly influence the pallet’s strength and durability. They include driven nails, staples, bolts, wood screws, and lag screws. Most wooden pallets utilize one of two types of nails, including helically threaded or drive-screw nails and annularly threaded or ring-shanked nails.
Helically threaded nails feature continuous spiral threads along the shank. Annularly threaded nails come with numerous rings along the shank that help grip the wood and prevent nail withdrawal. Of the pair, helically-threaded or drive-screw nails are the most popular choice for automated pallet assembly. Both types, however, are widely used by pallet manufacturers.
Pallets designed for heavier loads may also use bolts or screws in addition to nails for added strength.
The Anatomy of a Wooden Stringer Pallet
So, there we have it. The parts of a wooden stringer pallet seem simple: top deck boards, wooden stringers, bottom deck boards, plus fasteners. But the magic lies in selecting and combining those ingredients to provide the most cost-effective and sustainable option for unit load and for your supply chain. Contact PalletOne to help you connect the dots.
