Glossary
Companion stringer
Also called: sister stringer, stringer repair, sistered stringer
Reviewed
A companion stringer is a repair component fastened alongside a damaged stringer to restore its strength, instead of replacing the stringer outright. The Uniform Standard lists companion stringers with plugs, C-blocks and metal connector plates as recognized pallet repair methods.
On this page
How it is used
A cracked or broken stringer is reinforced by fastening a second stringer-sized piece alongside it, spanning the damaged section. The deckboards are then renailed as needed. Other repair components in the Uniform Standard include:
- Plugs
- C-blocks
- Metal connector plates
Repair rules to know
- The Uniform Standard defines repair classes and recommends a repair mark on the pallet showing class of repair, repairer ID, date and owner
- In the PDS service-life simulation, stringers can be repaired twice and replaced once
- Repaired pallets used for export must be re-treated and re-marked to ISPM 15
Why it matters
Companion stringers let recyclers return a pallet to service quickly and cheaply, which is central to the remanufactured pallet market. Buyers who do not want repaired stringers should say so in the spec, for example by specifying new manufacture or a recycled grade that excludes them. See recycled pallet.
Questions
- Are pallets with companion stringers acceptable?
- They are a recognized repair under the Uniform Standard. Whether they are acceptable depends on the buyer's grade and repair requirements.
Sources
- Uniform Standard for Wood Pallets (NWPCA, now Woodpack Global), 2012 edition
- Guide to Understanding the PDS Specification and Analysis (stringer, inches)