How does a company set about creating the perfect racking system? Some simple guidelines on the best approach will ensure that racking will fit the purpose.

Understand the pallet

Understanding the size, shape, strength and configuration of the pallet and load is the most critical component of the racking system. A number of issues need to be carefully analysed for each type of pallet to be stored.

Take into consideration the uniformity of the pallets; the height, width and length of the pallets; strength (load rating) of the pallets; direction of entry (which side of the pallet faces the aisle); type and position of pallet bearers; depth of pallet and fork entry criteria; the total mass of the load; stability of the load; load overhang; need for stock rotation (first in/first out?); and load identification.

Only once the unit load is understood, can the choice of rack configuration begin.

Height and configuration of storage system

If racking is to be installed in an existing building, the height of the storage system is usually dictated by the building height and the storage/picking technology to be used. If a new building is being developed then the picking/storage technology will dictate the storage height. For example, if a new facility is being developed and conventional reach truck networks (the most common warehousing strategy) are to be retained, the system limits may typically follow the parameters in Table 1.

What about the support beams?

It is important to ensure that, when storing pallets (especially four-way entry pallets) that the beams support the pallets under the bearers. If, for example, a pallet is stored 1 200 mm deep, the beams depth would typically be set at 1 100 mm to ensure the pallet is supported in the correct position. In a case where there is no pallet overhang allow 100 mm clearance between pallets and from the pallet to the frame, giving a beam length of 2 300 mm.
The beam pair capacity would be 2 x 800 kg (ie 800 kg per beam). Typically, add some safety factor and specify a capacity of 1 000 kg per beam.

What about fire protection?

Any racked system above 4 m high should have some form of in-rack fire protection (unless product and pallet stored is not flammable).

The configuration of the sprinkler system will depend on the flammability of the product; the manner in which the product will burn; the height of the pallet; the height of the rack system; and the aisle width.
For example, if the pallet and load are highly flammable, sprinklers may have to be installed in the back-to-back clearance at every level. It will also be necessary to leave a 250 mm gap between pallets to allow installation of sprinklers and spread of water if the sprinklers are activated.

Rack protection

Once the configuration of the system has been developed it will be necessary to examine rack protection.
For example, given a frame load of 11 200 kg, if a forklift were to collide with or even bump the rack, there is a real chance of collapse. It may be necessary to decide whether to install frame protection for each frame.
Standards

By now the mechanics of the system have been identified, including: unit load, beams, frames, fire protection, rack protection, clearances, aisles and run-outs. The system should also comply with all the necessary safety standards. These may include the Occupational and Safety Act, local municipal building legislation, and the appropriate rack manufacturing and erection standards.

Buying from a reputable supplier

Once a detailed knowledge of the type and configuration of the racking is established and an initial materials specification is established, rack suppliers (local and imported) can to be approached for a quotation, and ultimately supply and erection.

Certain supplier qualities need to be established. Does the supplier have a good reputation, extensive experience, produce good quality, assemble to specification, maintain a logical standard, deliver on time, and support the system after delivery?
Assembly

Finally the rack should be assembled and installed accurately and safely. Ensure the supplier has a properly structured programme; effectively fixes the rack to the floor; assembles the rack safely; and that the system is fully compliant before handover.

Configuring a rack system is no easy task. There are many variables, and the system will depend on variable issues such as throughput, number of lines handled, picking, packing, stock rotation, temperature zones, safety, access, and probably many more. The development of racking thus needs careful thought and lots of analysis – and all before buying.