Truly efficient lean manufacturing should include practices beyond the ­production line, including stock, components and WIP. Keith Couzens of Couzens Storage Solutions takes a close look at this vital part of modern assembly and manufacturing that is still often neglected, but which has the potential to provide big savings and improvements in productivity

Toyota’s established concept of Lean Manufacturing focused a telling light on the importance of storage and handling. ‘Each time a product is moved it stands the risk of being damaged, lost, or delayed, as well as being a cost for no added value.  Inventory – whether raw material, work-in-progress (WIP) or finished goods, represents a capital outlay that has not yet produced an income either by the producer or for the consumer.’

The message must be that by taking a more radical view on how components and materials are stored and handled – and making the right level of investment – companies have the opportunity to both streamline their warehousing and improve production and assembly performance.

Modern storage systems have been developed to take advantage of the latest IT and software developments, able to interface and integrate with other processes in manufacturing and assembly. At the same time they are able to make far better use of cube space than was the case with conventional racking and shelving systems, and can handle a variety of different materials and products in one unit, as well as improving picking efficiency, accuracy and speed.

Vertical lifts provide the most advanced form of storage and retrieval systems, designed to support assembly and manufacturing operations, as well as storage and distribution facilities. They provide outstanding use of space, freeing up to 90 per cent or more of the floor area required by conventional storage systems. But that’s only part of the story. 

A typical design such as the Modula Vertical Lift incorporates a series of trays stacked vertically in a range of sizes up to 4.1m x 85.7cm, which can be used for an almost limitless variety of storage media and items. Different sized totes, boxes and adjustable tray dividers enable the user to stock a vast quantity of various items and materials, all in their place and instantly ­visible to the picker.

The operator simply selects the required items using a touch screen PLC linked to the client’s stock management system and the right tray is automatically presented at a comfortable picking height in seconds.  Once picked and scanned if required, the system automatically updates stock records so an accurate, real time picture of stock held is always available. Picking lists to support an assembly process can be prepared in advance so the operator can pick all the items required from a single location and have each completed batch ready as and when required, to avoid any ­production hold-ups.

While ideal for small items such as electronic components, chips and the like, each tray in the machine can carry up to 750kg, so the same unit can easily accommodate heavier and bulkier components and materials.

Stocks are far more secure and protected from loss, damage and shrinkage. Each Modula unit is enclosed within a steel panel frame and can have badge and password entry systems to ensure strict access control to approved staff.

Two Modula units being used by aluminium profile building systems company SAPA vividly illustrates the flexibility and cost-saving potential of investing in advanced storage technologies. The units hold around 153,000 items and 1,258 lines including fixings, seals, handles, brackets and other components to support ­production and customer installations. As well as improving staff ­efficiency and production quality, SAPA now has now consolidated three facilities into one, making savings far beyond the capital invested.

At the other end of the scale, many companies hold raw material stock in the form of heavy metal sheet, bar, ­profiles and other awkward components. Our TowerMat Vertical Storage systems provide the same space saving efficiencies, security and fast picking as the Modula range, but with up to five tonnes capacity for each cassette, and close to a million kg per machine has been achieved.

A powered cart helps to present items selected so that they can be ­handled safely using an overhead crane or fork truck, minimising the risk to staff and of damage to what can be costly raw materials.

Not every business can achieve the success and productivity that leading companies such as Toyota can. But the lessons are universal. Successful companies constantly review every aspect of their operations and are ­prepared to invest in big decisions to yield big returns.

Couzens Storage Solutions

T: 01442 250010