Storage has an appetite. It's hungry for space. It gobbles up resources in the form of time and manpower. It feeds off ignorance and indecision. Most importantly, it devours your profits. Strange then that, although storage does all the eating, it's often you – the factory manager – who ends up with indigestion.
Well, the good news is that you can write the recipe for storage success. First course on the menu is an understanding of the principles of efficient storage. Broadly, its aim is to bring the right stock in the right quantity to the right place at the right time. So, effective handling and storage:
- Makes full use of available space.
- Maintains stock at an economic level.
- Speeds selection dispatch.
- Minimises damage and deterioration.
Static manual picking is relatively simple and offers storage flexibility. However, Edward Hutchison, managing director at Bito Storage Systems (http://uk.bito.com), has detected a shift in UK factories towards 'live' storage which is designed primarily for high volume order picking using 'first in, first out' stock rotation.
He says: "Companies are installing banks of flow shelves for new or additional pick zones in free areas of their warehouses or factories to gain faster picking, reduced manpower and improved space saving and organisation."
Constant availability of goods
Hutchison believes many manufacturers are replacing traditional static shelving in the lower bays of their pallet racking with flow shelves when they lack free areas on their shop floors or in their warehouses: "By concentrating cartons into flow lanes, 'carton live storage' provides a dense storage system that will also increase productivity. Cartons of goods fed into the system at the rear can flow unassisted down rollers in a lane designed around the carton or container to be presented at the front on the pick face. This means pickers have constant availability of goods."
Live storage is also suitable for pallets and companies often combine them with cartons to suit different types of SKUs and throughput speeds.
Hutchison estimates that the greater pick location density offered by live storage saves up to 20% of floor space for small parts storage compared with static shelving, while travel time for pickers can be improved by 66%.
Of course, the type of storage you specify will depend on the nature of your business and the products it manufactures so the message is invest time and money into researching and implementing the specific storage requirements you need.
As Lionel Drage, a rack inspector and MD of Storage Equipment Manufacturers Association (SEMA)-approved installer Birchmoor Associates (www.birchmoorassociates.co.uk), says: "Factory managers need to first look at the type of product that they are storing. If they are high volume bulk goods which are not date sensitive, then it's not necessary to have access to every box and a high density storage system is most applicable.
"If you have a vast array of SKUs, then you will need full access to every product so a high bay pallet racking system with a man riser order picker is likely to be the most efficient."
There are four major specification criteria when it comes to handling and storage. The first is space utilisation. An efficient store is one where the available space is used to the full and handling time is reduced to a minimum. Ease of access to stored materials and speed of retrieval are features that all efficient stores have in common so minimum travelling distances and logical order picking matter.
Drage says: "Many producers do not optimise the space at their disposal. For example, I made a recent visit to a 12m high facility housing one third of high bay very narrow aisle racking and the remaining two thirds was occupied by 2m and 3m high shelving. When measured up, their (wasted) airspace was 9m across two thirds of their facility."
He says that, had the company installed a two tier mezzanine or an automated storage and retrieval system, its resources would have been compacted into a quarter of the warehouse space and the remainder released for manufacturing or other uses.
Rapid Racking's Matt Danhieux (www.rapidracking.com) agrees it's critical to "utilise the cube". He says: "Are you making use of the height of the building? Could a shelving system be a two-tier, or would a mezzanine floor be more suitable? You may also be able to provide storage above a manufacturing area, or office space over a storage area."
The second criterion is health and safety. Risks here include manual handling/musculoskeletal disorders; work at height; vehicles in and around the warehouse; and especially slips and trips. Around a quarter of major injuries (broken bones and other injuries requiring hospitalisation for more than 24 hours) in the warehousing industry are caused by workers slipping or tripping. The Health & Safety Executive has published useful guidance to safe storage (http://bit.ly/1duwSfH and http://bit.ly/1Ar9EBr).
Check the racking specification
It's also important to make a judgment about whether the racking is safely specified for the correct loading conditions, says Danhieux: "Does it need upgrading for a change in use – eg, heavier pallets? Pallet racking systems may be fitted with safety features such as anti-spill mesh to prevent pallets falling through the back of pallet racking. But think about stability of hand loaded shelving systems: does it need to be floor fixed?"
Thirdly, consider damage control. Andy Timmins, managing director of ROS UK (www.ros-uk.com), warns: "Damaged racking uprights present a huge cause for concern within the warehouse environment, with the structural integrity of the racking being severely compromised with every forklift truck impact.
"Further problems arise when the affected pallet locations have to be closed down and unloaded, with cost and time implications."
However, he adds, the challenges don't stop there: "There are also expensive replacement material costs as well as installation, forklift truck hire and scissor lift hire to factor in. Suddenly, you are presented with an unexpected bill running into many thousands of pounds, in addition to the enormous operational disruption which comes with traditional racking upright replacement."
Finally, look at the accuracy of component/product retrieval. Products aren't bringing in cash while they're being stored; the quicker they can be sorted, selected, retrieved and sent out the better. So get the storage suppliers' advice on the best options.
Having ascertained what you need from your storage system you can decide which system is best suited to your requirements. There are a number of potential solutions, including:
- Pallet racking – basically an open framework consisting of upright beams and bracing. There are several kinds.
- The most common type is adjustable, which allows general-purpose forklift trucks to manoeuvre in the aisles between racks.
- Narrow aisle racking provides high-density storage while still permitting individual access to each pallet, but requires specially designed vehicles.
- Drive in and drive-through racking are continuous blocks of racking that are not divided by aisles. Drive-through racks can provide 'first in first out' storage. This is possible because there are no cross beams to interfere with entry; pallets are supported on cantilevers.
- Mobile racking is fitted with rollers and runs along floor rails. This allows aisles to be opened up or closed at the push of a button.
- Take the idea of racking a stage further and you get the rack supported building get a construction method in which the racking itself forms the supporting structure of the building.
- Shelving – includes long and short span, cantilever, high rise in mobile. Shelves provide a flat, continuous surface upon which a variety of items can be stored. Shelves are ideal for bulky items. Shelf dividers, drawers, beams and boxes can be used to compartmentalise smaller items.
- Carousels – essentially consist of beams linked together to form a loop, either vertically or horizontally. The appropriate bin is brought to the operator mechanically so that he or she does not have to move far.
Don't make the mistake of automatically going for the cheapest option. Danhieux warns: "Cheaper racking, particularly for industrial use, isn't guaranteed to last and may not fulfil your business requirements in the longer term; it could be quickly outgrown by the business, or end up battered and unsafe after just a few months. It's much better to get it right first time."
He also recommends using an accredited fitter: "Always insist on a Storage Equipment Installers Registration Scheme (www.seirs.org.uk) registered installation team who are required to follow the SEMA (www.sema.org.uk) installation guide and code of practice which guarantees that the latest health and safety guidelines will be followed throughout."
Remember, storage suppliers are there to help you so make use of them. But whatever your storage needs, don't rush into a decision. Once you've put a storage system in, you're committed to it for a long time so consider your priorities, assess the systems available and then choose the one that best fits the bill. An orderly approach can result in a neat solution and a tidy profit.
