When a damaged rack section is assessed by a qualified, professional rack engineer, it may be determined that a repair can be completed with a rack repair kit as opposed to field welding. That’s because, as outlined in Appendix 1 of RMI’s publication “Guideline for the Assessment and Repair or Replacement of Damaged Rack – Version 1,” there are several risks associated with field welding, including fire, potential for weld contamination and the work being performed in an improper ambient temperature, compromising the weld.
With those field welding risks in mind, the majority of RMI manufacturers offer “bolted” upright frame repair kits. These engineered kits may allow damaged sections of rack to be removed and replaced with a like-new product that has been properly designed and bolted in place, eliminating the complexities associated with a welded repair.
Before undertaking a kit-based rack repair, it’s important to understand that kits are not comprised of standard, off-the shelf components. Instead, they must be engineered to match the configuration and loading of the existing rack at the location of the damage. Their creation takes into account all the loads being imparted upon the damaged component—not solely upon the particular member being repaired. Further, each load configuration must be evaluated separately, and the repair kit must be engineered to meet applicable building codes.
In non-seismic areas, a properly-engineered repair kit might include:
- A thicker or reinforced column
- A splice at mid-height between the shelves and above the damage
- A splice design that is stronger and stiffer than the original column
- A frame bracing pattern that continues from the floor to just below the splice
- A baseplate that is stiffer and with more robust anchorage
During RMI’s recent ProMat 2019 on-floor educational seminar, “Storage Rack Safety 101,” rack repair kits were highlighted. One of the points noted was that a rack repair kit must maintain frame bracing continuity, meaning it must match the bracing of the original rack design and have a continuous load path from above the splice to below the splice. When determining the appropriate column splice for a given repair, engineers have a choice of two styles: a splice designed to bear the load when integrated into the racking system, or a splice that utilizes heavy-duty bolts to bear the load.
Moreover, when the new column base is placed on the floor, it should be anchored using different holes than the previous plate utilized to ensure it is properly affixed. If any open holes remain in the floor, the new anchors can be placed 3-bolt-diameters (center-to-center) away from an empty hole without reducing its pullout capacity. If the holes have been filled with dry-pack mortar, a new anchor may be installed 1.5-bolt-diameters (center-to-center) from the filled hole.
Although third-party aftermarket repair kits and services are available, it is critical to have an engineer familiar with rack or the original rack manufacturer review and approve a third-party’s proposed kit’s design to ensure its installation preserves the structural adequacy of the original system.
To ensure that the rack repair kit used to replace damaged racking components, best practice is to work with the original rack manufacturer and a qualified engineer. This enables a rack owner to be confident that the repair work will be fully compatible with the current system and continue to provide a safe working environment for their workers.
Upon the repair of any rack structure—whether by the original equipment manufacturer or a third-party—the Load Application and Rack Configuration (LARC) drawing must be updated to show the fabrication and installation details and all repair locations. The new LARC must be signed and sealed by the rack design professional engineer, indicating their approval of the whole rack system with the repair kit installed.
Want to learn more about rack repair? Download RMI’s Guideline for the Assessment and Repair or Replacement of Damaged Rack – Version 1.