Very Narrow Aisle (VNA) systems can significantly improve efficiencies and productivity within any warehouse or distribution centre operation. However, when designing a VNA system, it is not unusual for insufficient attention to be paid to the specification of the warehouse floor and this can have a dramatic impact on the overall performance of the equipment, says Steve Richmond, general manager of Jungheinrich UK Ltd’s Systems & Projects Division.
If a VNA storage system is failing to reach optimum levels of efficiency the user’s first reaction is, generally, to assume that the trucks are underperforming. In most instances, however, this is not the case: more often than not the fault does not lie with the equipment but the surface it is operating on.
“The floor is the point at which the warehouse building and the truck interact and quite simply, a poor floor will result in poor VNA performance,” says Steve Richmond.
Steve believes that the design, specification and final finish of the warehouse floor is absolutely critical to the optimised operation of VNA trucks. And, he contends, with truck manufacturers pushing the physical design of the equipment close to maximum efficiency, the performance of the floor will come under ever greater scrutiny.
“You can invest in the best forklift trucks and materials handling equipment on the market, but if your warehouse floor resembles a ploughed field, the trucks will never be able to operate at their top speeds or optimum efficiency – think of it as driving a Ferrari down a cobbled street,” he says.
Whether faced with a new building where the floor has been laid to a particular specification or an existing site that is to be modified to accommodate a VNA application, a warehouse’s floor will present different challenges.
When installing VNA systems, the responsibility for specifying the level of the floor finish required lies with the truck manufacturer and there are accepted industry standards that lay down the specification which the flooring should meet. The responsibility for achieving this specification lies with the flooring contractor. The relationship between the flooring contractor and the materials handling supplier is therefore critical and so, to ensure that everyone is working towards the same goal, a floor survey is always highly recommended. The survey will highlight any remedial works that might be required – as well as the extent of the works and should be used as a basis for all parties to assess the condition of the surface and its likely impact on the operation of VNA equipment.
From the outset, it is important to realise that floor flatness and floor level are two different things and their respective effects on the operation of a truck are totally different. According to TR34, the Technical report from the Concrete Society, flatness relates to the “bumpiness” of the floor and general stability in operation of the truck. Floor level relates to the building as a whole and has to be right to ensure that both static and mobile equipment can perform satisfactorily together.
“Effects from the floor, can cause trucks to move from side to side or in a front to back ‘nodding’ motion as they travel along the length of the aisle. In some scenarios the movement of the trucks may be so significant that there is a potential for them to come into contact with the rack structure ” comments Steve Richmond.
“Meanwhile,” he adds, “even relatively small differences in the floor level within a racking aisle can have a significant impact when the truck is operating at heights often in excess of 15 metres. The higher the mast height, the more pronounced the ‘lean’ from uneven floors and the greater the potential problem.”
Jungheinrich UK Ltd