RACKING & SHELVING – Reviewing racking and shelving can cut costs – The comment from Warehouse & Logistics News

At a time when business is slack the need for squeezing maximum use from a warehouse is all the more urgent. So perhaps it’s time to take a fresh look at the racking and shelving inside it, and whether it’s right for your current usage of the building. New businesses looking for storage may be tempted to choose second hand racking/shelving in the current, strained business climate, which is fine provided certain procedures are followed. Buyers need to be very cautious because the racking may have hidden damage and so a thorough examination is essential. Damaged racking should be repaired according to the rack maker’s guidelines and racking audits are best left to experienced engineers. Buyers should also enquire if the rack producer who is installing the racking is using only its own, dedicated staff or whether that function has been subcontracted out. The latter course has led to some disastrous racking collapses in the past.

The Storage Equipment Manufactures’ Association (SEMA) has improved safety here by introducing its SEIRS (Storage Equipment Installers Registration Scheme) earlier this decade. To qualify for a SEIRS ID card installers much successfully complete a SEIRS category A  safety training course.

The problem for storers of many different types of goods is that the racking/shelving choice becomes much more complex than when goods are homogenous in size, categories and have the same throughput rates. Cold stores operators, for example, will invariably be driven towards mobile, drive-in and live racking, all of which are high density storage methods, a crucial consideration given the high energy costs involved.

Mobile racking offers at least 50% more storage density than narrow aisle APR racking as well as instant 100% selectivity. Product access times, however, are slower because aisles must first be opened before loads can be accessed. Hand-cranked mobiles are usually limited to shelving where maximum load movements are about 30 tonnes. Powered mobiles can move loads of several hundred tonnes and be activated by drivers on their forklifts.

Mobile racking’s initial cost is around three times higher than APR racking, which encourages users to seek drive-in or drive-through racking, which offers similar storage density. However, instant selectivity is a poor average of 30% and based on first-in last-out. This racking type is also notorious for high damage levels.

The third cold storage racking method, flow storage, initially may cost twice as much as drive-in but buyers should consider the long-term cost of ownership. Studies show, for example, that live racking could emerge one third cheaper than drive-in. This is because the average utilisation of drive-in is only 60% compared with 90% for live storage. The latter could also save 12.5% of ground area, which has important implications for building and running costs.

A more recent innovation is push-back racking, which combines the major benefits of drive-in and live storage. The racking’s rear can butt up against walls because pallet replenishment and picking is done from the same face. This form of racking, however, is limited to six pallets deep.

As with forklifts, racking and shelving can harness information technology. Most popular of the devices are the pick-to-light systems incorporated into shelving edges. It can cut out much wasted time spent walking, is for more accurate than paper-based picking and instantly updates stock levels in real time.

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