What is wire decking and how does it differ from other types of rack shelves?
Wire decking is a decking system used on pallet rack shelves. Its purpose is to provide additional support for stored materials, as well as, becoming a safety net for unstable loads. Wire decking is fabricated from welded-wire mesh, and generally has reinforcements in the form of channels or support wires. Wire decks are supported by the rack beams at the front and rear and the strength and stiffness of the wire deck system provides support for the load between the beams. Decking designs vary greatly depending on the application. Wire thickness, grid pattern and number of channels all have an effect on performance.
Wire decking is unique to other types of shelving not only in appearance but also in performance. Because wire decks are made of steel, their integrity, capacity and performance remain constant. The advantages of wire mesh decks include safety, greater capacities, their ability to allow light, air, debris and water (very important in some states due to fire codes) to pass through the decks.
Should I buy used racks?
Racks that do not conform to the ANSI/RMI Specifications may not be as safe as racks that conform to the specification. The Rack Manufacturer’s Specification is the only recognized U.S. specification for the design, testing and utilization of industrial steel storage racks. If there should ever be an accident or other incident involving the storage racks, a responsible rack user may want to show that its racks have been designed to meet this recognized standard.
The RMI recommends purchasing racks that clearly meet the requirements of the ANSI/RMI Specification.
Do I need column protectors? If so, what kind?
Column protectors are often used to protect rack columns from possible collision damage in traffic aisles of rack storage systems. The nature of column protection may depend on the particular rack system and the vehicles which are used to service it. With inattentive operation, columns may be struck by man-operated forklift trucks directly or by over-hanging loads being carried by those vehicles.
It is not always feasible to build, install, and operate rack systems that are immune to such dynamic operational abuse. Column-protectors, fenders, bumpers, or deflectors are often installed in front of each exposed rack column to attempt to keep such misuse from damaging the rack columns; aisle guides may also be used to attempt to keep a man-operated forklift from going astray; or reinforcement may be added to the exposed aisle-side columns with additional column sections, other reinforcing steel or other materials to improve their impact resistance. Automated or wire-guided vehicle systems are normally constrained on their intended path and are thus less likely to damage traffic-aisle rack columns. Users should consult their rack supplier about the various available protections, considerations, and options. (See ANSI/RMI, Specification section 1.4.9 and Commentary section 1.4.9).
What are the most common types of wire decks?
(a) The most common type of wire deck is a waterfall style. The waterfall is the overlapping of the top deck wires running over and down the face of the support beams, resembling a waterfall. They usually have three to four support members or channels designed to fit within the step of the beam and support the load resting upon the deck. A waterfall deck for a box or structural beam is the same as above with the exception that the support members or channels are flattened or flared at the ends where they rest on the top of the rack beam.
(b) Another popular type of wire deck, similar to the above, is a flush or instep deck fitting step beams only. This deck sets on the step ledge between the beams, flush with the top of the beams. It can be flat or have formed instep waterfalls. The purpose of the design is to avoid any potential snag points and to leave the rack beam face unobstructed.*
(c) Also available is a non-waterfall deck that may span across the top of the front and rear load beams but does not waterfall down. This style of deck is not recommended for non-step beams due to the configuration being unstable.*