Anatomy of a Warehouse Part 1 - Racking

Welcome to the first in a series of blogs aimed to get into the heart of a warehouse. We recently published a piece on pallets – this series will cover racking, forklifts and ancillaries. After pallets, the place to start the dissection is racking, the backbone of a warehouse. There are a number of formats of pallet racking for warehouses, all with the aim of increasing the pallet storage density of the warehouse space.

Pallet racking is essentially made of uprights and horizontals. There are two main standards of construction: roll formed racking allows the horizontal beams to be attached to the uprights by clips, effectively dropping the horizontals into position. This enables quicker re-positioning of the beams to accommodate taller or shorter pallets with optimum warehouse space utilisation. With structural pallet racking pallet rack systems have the beams attached to the uprights by bolts – less quick to change but capable of higher load bearing.

The most common pallet racking format is back to back rows of a single pallet depth each accessible with a standard forklift, thus requiring 2-3 metres access between the rows. However, there are variations, the choice of which is usually governed by a combination of the warehouse dimensions, product complexity, pick type (singles or full pallets) and the uniformity or stack-ability of the pallets.

Very Narrow Aisle (VNA) racking has much narrower aisles and requires specialist forklifts, often running on rails or wires between the two racks and able to access both sides of racking without lateral movement. These forklifts, which may be automated, then leave their picks at the end of the aisle for further movement around the warehouse. Clearly VNA increases warehouse space utilisation, at a cost of higher capital investment, possibly slower pick speeds and additional movements. They can be particularly efficient for picking slow moving pallets.

Drive-In/ Drive-Through pallet racking allows greater depth of pallets by aligning them in rows, thus using space better but at the cost of not being able to pick each single pallet (unless pallets in-front of it are removed first). This format suits multiple pallet stock of the same product. Drive in racking allows access to one end of the stack first, thus meaning the last pallet in will be the first pallet out (LIFO). Rotation can be achieved by having two or more rows for a single SKU and emptying one first before moving on to the next pallet row for outbound pallets, and back-filling the former with new inbound pallets; though this starts to reduce the space efficiency of the drive-in racking. Drive-through racking has access at the front and back of the row, thus allowing first in, first out stock rotation (FIFO). Each additional pallet added at the back pushes all the pallets forward (usually on rollers) so the oldest one presents itself for the next pick.

Push-back pallet racking systems are a variant of drive-in whereby a new inbound pallet pushes back the row of pallets. Once the front pallet is picked, a combination of incline and rails slides the next pallet to the front picking space. This system can be made FIFO like drive-through, by inputting pallets at the back.

Mobilized pallet racks are another way of optimising warehouse space, particularly for slow selling stock. A number of racks (but probably not more than 3 or 4) are aligned against each other such that only the first one (or maybe the middle two) are accessible, this saving the need for several aisle widths. These racks can be moved by motors on rails to allow the required rack to be accessible for the pallet pick.

A Google search for ‘Warehouse racking suppliers UK’ delivers the following top 5 organic results:

  • Rapid Racking – founded in 1986 in Gloucestershire, Rapid Racking claims to have been the first supplier in the UK of boltless pallet racking by mail order. As well as lightweight pallet racking, the company supplies shelving, boxes and containers, file/document/small parts storage systems and workshop, workplace and warehouse accessories.
  • Dexion - after starting as a printing business, the founder of Dexion needed more space and, in 1947, invented an easy to assemble and dissemble small parts racking system. Dexion now supplies a wide range of warehouse racking solutions - pallet racking, shelving systems, cantilever racking, mezzanine floors and vertical/automated small parts storage.
  • SEC – based in Stevenage, SEC has been in the racking business since 2000 and supplies the full range of heavy duty warehouse racking: standard pallets racking, VNA, double deep, drive in, cantilever and push back.
  • Stow – part of the Averys Group, Stow has warehouse racking solutions for pallets, small goods and long items as well as mezzanine floors. It has production plants in Belgium, Shanghai and the Czech Republic.
  • Avanta – established 20 years ago and based in Leeds, Avanta supplies pallet racking, shelving storage, office and steel partition and mezzanine floors.

Other suppliers of warehouse racking include Redirack, Warehouse Storage Solutions and Pallet Racking Systems. The latter is an example of the large market in second hand and re-conditioned racking. Because pallet racking essentially a huge Meccano set, and rarely customised to be warehouse specific or integral to the warehouse infrastructure, second hand racking can be a cost effective way of fitting out a warehouse.

Warehouse racking is usually protected to ensure forklifts do not cause material damage. Pallet racking protection is supplied by most of the above. Rackamour is a notable specialist in this field too.

Zupplychain’s database offers racked warehouses for pallet storage across the UK - to search for pallet storage and warehouse space, visit us today !