With the explosion of e-commerce, the flexibility mezzanines provide is becoming the warehouse’s Holy Grail. Alexandra Leonards reports…
The nature of the warehouse is shifting, and with that change comes the elevation of mezzanines. They handle growth for companies that need more space for distribution or production – and this is a quality that is highly sought after in today’s logistics industry. Warehouses are getting taller and taller every year, as businesses reap the benefits of mezzanines.
“From recent projects that Nerak has delivered, it is clear that e-commerce growth is a key driver behind firms wanting to exploit their existing footprint fully,” says Simon Musgrave, sales director, Nerak Wiese. “A recent example is the two lifts we supplied to XPO Logistics at Missguided’s new DC in Manchester – which features four mezzanine floors – to transport cartons from goods-in to the order picking areas and back.”
Mezzanines provide an unmatched level of flexibility in an environment that is seeing a great expansion in the number and types of products stored and sorted in a single warehouse.
Mezzanines provide the flexibility needed for operations that are ever expanding due to the explosion of e-commerce and the wide variety of items that can be stored in a warehouse these days. “In today’s changing marketplace, the need for extra space that is flexible – so that its use can be modified as operational needs evolve – is critical,” says Derek Scott, projects sales manager for mezzanine floor manufacturer, Davicon. “If you consider that today you may be picking cartons or totes and tomorrow you could be picking garments on hangers, then the flexibility of a near-open space is a key driver in selecting a mezzanine floor.”
Scott says that almost all existing warehouses have unused space – normally above existing operations, over loading docks or where shelving has been installed on the ground floor. “Making use of these areas allows new, value-added operations to be accommodated, while keeping ground floor areas clear for marshalling and compressing storage footprint,” he adds. “If you are considering a new warehouse, then introducing a mezzanine with multiple levels can either reduce the size of the warehouse you need – thereby reducing costs – or allow for future development in the same space.”
There are some really important considerations a business needs to make before installing a mezzanine into its warehouse. As well as both designing and specifying the right type of mezzanine floor, companies also need to consider how the floor will be used. “In most warehouses, this will mean deciding how goods will travel between the floors,” says Simon Musgrave, Nerak Wiese. “If throughput is at a reasonable level, relying on the availability of a forklift and driver to move goods up or down is likely to cause a bottleneck in operations.
“A dedicated vertical conveyor is a much more efficient solution. Depending on the application the client might opt for a pallet lift, a continuous platform elevator, a dolly lift, a paternoster, a reciprocating hoist or a spiral conveyor.”
Nathan Miller, technical sales, major accounts at Mezzanine International says that for a new build, the mezzanine is the first structure to go in. “So the whole technological warehouse solution is build around it,” he says. “If the design and installation are out then it impacts the entire build programme.”
For an existing warehouse, the condition of the ground slab can dictate the mezzanine scheme and design. “So careful consideration needs to be given to the slab when redeveloping an existing space,” adds Miller.
Musgrave says that another fact to consider is the on-going cost of serving the mezzanines. “This is where an automated solution – avoiding the cost of a truck driver and time-consuming battery charging – can pay dividends,” says Musgrave. “Mezzanine lifts usually require only an annual service to keep them running smoothly – and Nerak lifts feature our unique rubber chain technology, making them resistant to wear and corrosion and avoiding the need for lubrication.”
Derek Scott from Davicon says that there are a myriad of factors driving the need for mezzanine floors in today’s marketplace. “Number one is normally the need for additional space, be it for storage or operational challenges,” he says. “However, the important questions are: whether you have the space, particularly the height; what the warehouse floor will take load-wise; and what you want to put on the new floor space.”
Flooring solution for tea processing plant
Sikafloor supplied its flooring solution for the owners of a tea processing plant who required a new surface installed without interruption to warehouse staff or production.
The company’s warehouse floor had become dilapidated over time due to constant use of heavy machinery and foot traffic. The plant’s owners selected contractors Thelwell Flooring to install a new surface which was not only durable enough to withstand the long-term rigours of warehouse activity, it had to be easy to install and fast-curing to ensure production work could continue unencumbered at the plant. Sikafloor-31 PurCem possessed all the properties to meet these precise requirements.
A 1,200 sq m area of new flooring needed to be installed after the original concrete surface became cracked and broken in places. The first 1mm layer was installed following repairs to the original substrate which also required decontamination.
Sikafloor-31 PurCem is a multi-component, cement and aggregate coating with chemical, abrasion and mechanical resistance. It is also solvent-free, making it ideal for use in an environment where food is stored or prepared and susceptible to odour contamination. Following the first coat’s application, a second one was installed to the same 1mm thickness.
The floor’s refurbishment was carried out in stages over a period of four months to minimise disruption to the plant’s daily operations. For the contractors, this meant weekend and out-of-hours working to ensure newly-laid areas of flooring could meet the demands of forklift and other machine activity when warehouse work resumed at the beginning of the week.
“Sikafloor-31 PurCem was the only system for this project where speed was of the essence to ensure the refurbishment didn’t interfere with the plant’s production process,” said Mike Thelwell, director of Thelwell Flooring. “It’s extremely easy to install and because it has very low VOC emissions and is solvent-free, it eliminated the risk of tainting food and other edible substances stored within the plant.
“It’s a quality system, and will withstand the long-term use of the sort of heavy traffic you would expect to find in a warehouse environment.”
The Sikafloor-31 PurCem was installed in two colours throughout the warehouse – grey to denote pedestrian-only areas; blue for forklift traffic.
The robot effect
One of the biggest developments for mezzanines, as is the case across the logistics industry, is automation.
“The once humble mezzanine stuffed at the back of a grubby store area is now generally an integral part of a much bigger automated system,” says Derek Scott of Davicon. “The mezzanine now supports an integrated solution with larger imposed loads, dynamic force requirements and ever-decreasing deflection limits.
“This trend towards logistics automation has challenged mezzanine suppliers to understand the automated systems and provide the technical support and understanding that system integrators require.”
According to him, mezzanines are now being used more and more to support automated systems and processes.
“ For example, Davicon has delivered floors to support shuttle systems, provide multi-level picking areas, accommodate miniload cranes or A-frame automatic picking solutions and provide pick and deposit platforms for ASRS and the associated pallet handling required,” he says. “Our floors have supported pallet conveyor, monorail systems, garment-handling automation, tote conveyor systems and tilt-tray or cross-belt sorters.”
Its latest systems are now even looking at supporting robots – either articulated-arm models or AGVs. “Whereas mezzanine loadings range from 2.5kN/sqm to 10kN/sqm as standard when you start looking at putting a shuttle system on a mezzanine, you are increasing these loads greatly with deflection limits of less than 4mm – and the possibility of resisting a shuttle lift crash making things just a bit more challenging,” he says. “The movement towards automation in the world logistics market has seen a upsurge since 2015, and we don’t see it decreasing any time soon.”
With this in mind, the biggest challenges for mezzanine suppliers it to keep pace with the requirements of automation.
Missguided gets a lift
Nerak Wiese has supplied two vertical lifts to XPO Logistics, operators of the warehouse for multi-channel fast fashion retailer, Missguided, in Manchester. Missguided opened the new distribution centre in Trafford Park in 2016 as a joint investment with supply chain partner, XPO Logistics. The 250,000 sq ft DC – which was designed to handle Missguided’s logistics needs for the next ten years – operates 24 hours a day, seven days a week.
With the DC featuring four mezzanine levels above the ground floor – providing a total floor area in excess of one million sq ft – the operation required a vertical elevation solution. XPO Logistics commissioned Nerak Wiese to design and manufacture two lifts featuring a unique design. Each lift comprises two independent hoists, each of which has two conveyors – mounted one above the other – and so can handle two loads. The lifts transport cardboard cartons of goods received from manufacturers up to the picking areas on the mezzanines. Here, staff pick orders into totes, which are then transported down to the ground floor by the lifts. In addition, the lifts are used to transport empty totes up to the pick areas, with three totes nested together during elevation. The throughput from the top floor is 250 inbound and 250 outbound loads per hour, per lift.
As the lifts are based around rubber chain technology, they do not require frequent lubrication or recalibration. From a service and maintenance perspective, the result is very little downtime, minimising the associated costs.
“This has proven to be a cost-effective and high-quality solution,” said Phil Shepherd, director of technical services for XPO Logistics. “The system works well and, in tests, the equipment exceeded the specification, so we are delighted and plan to buy a further two lifts from Nerak.”
This article first appeared in Logistics Manager, May 2018