See you at the drive-in
January 1st 2012

SEMA approved rack inspector and structural engineer at Storage Equipment Safety Service,Richard Taylor, shares his advice on the ins and outs of drive-in racking

Drive-in racking can provide high density and space-efficient storage of large numbers of similar types of loaded pallets, using only about two-thirds of the floor space needed by equivalent adjustable pallet racking.

These benefits come with some demands, however, in the form of careful design and installation, the flatness of the floor, the correct size and strength of pallets, and the right fork lift truck for the job. The various components must be maintained straight and undamaged, to carry their loads safely and to allow safe unhindered access for loaded pallets.

Hold true Pallets are supported along their edges on the silver coloured beam rails fixed to full height blue upright frames. It is essential that the framing is held truly vertical and square by the orange coloured spine and plan bracing, together with the orange coloured top portal beams, to ensure stiffness and stability.

Proper location The pallets must be in good condition, and properly located on the beam rails, because friction then holds the upright frames vertical under load. Incorrect placing can tend to cause sway, lateral forces which are only released when adjacent pallets are removed.

Insufficient support If pallets are incorrectly placed without sufficient support on one edge, or if they break under load, they can then drop easily and force the upright frames to bow sideways, allowing further pallets to fall, becoming very hazardous for a driver in the adjacent bay.

Beam rails Damaged or distorted components will either fail or collapse under load, or as in this case of a bent beam rail, will not provide sufficient safe support for the pallet edges. Slight disturbance may be enough to allow a pallet to drop, and cause impact and overloading damage below.

Friction hold Because the pallets are held in place by friction on the beam rail, disturbance caused by any local collapse has the possibility of initiating a more serious and widespread collapse, limited only by the size of the block of racking.

Front uprights Usually, impact damage is to the lower parts of front uprights, but can actually occur anywhere in the depth of the racking. If the racking is fully loaded, seeing and identifying damage to any components within the depth can be difficult.

Conclusion The continued safe use of drive-in racking depends on good and appropriate training of fork lift truck drivers, and correct procedures for placing and retrieving pallets. Guidelines and Codes of Practice are published by SEMA.

There should be regular damage inspections carried out by trained warehouse staff, together with an annual or bi-annual inspection by a SEMA Approved Rack Inspector, when broader safety issues would also be investigated such as pallet loading methods and continuing correct alignment of the racking.

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