Mobile Pallet Racking Systems

Mobile pallet racking is conventional pallet rack that has been set on motorized mobile bases instead of straight onto the floor. The bases run on rails embedded in or fixed to the slab. Because the rack rows can close up against each other, the building no longer has to give up floor area to an aisle between every pair of rows — the block travels sideways and opens an aisle only at the position the operator asks for.

That is the whole idea, and it is a geometry trade, not a magic trick. Take a block of ten double-sided rack rows. Served conventionally, that block needs an aisle between each pair of rows. On mobile bases, the same ten rows need one aisle. The floor those other aisles used to occupy becomes either more pallet positions in the same building or a smaller building for the same pallet count. How much you actually recover depends on your aisle width, which is set by your lift trucks, and on how many aisles you choose to keep open.

What you do not give up is selectivity. Every pallet still sits on a normal selective rack face, so once the aisle is open, any pallet in the block is directly reachable. That is the practical difference between mobile racking and deep-lane systems such as drive-in, push-back and pallet flow, which buy density by putting pallets behind one another and accepting last-in/first-out or fixed-sequence handling.

What the rails are asking of the floor

• Continuous support. A rail is only as good as what is under it along its whole length. Voids, soft fill and cracked slab edges show up as movement later.
• Level and flat. The rows have to travel without racking or binding, and the carriage has to stop at a repeatable aisle position. Levelling tolerance is set during install and is one of the reasons the tracks are levelled and fastened together before they are set.
• Combined load. The slab carries the rack, the pallets, the bases, and the lift truck driving across the rails into the aisle. That last one is easy to forget.
• A flush crossing. The rail surface has to sit where truck wheels can cross it cleanly, which is exactly what the four installation methods below are designed to achieve.

Everything about operating a mobile block comes back to one rule: the rows must not move while anyone is between them. The control package is designed around that rule, and the devices are layered so that no single failure removes the protection.

• Exterior safety barrier. With the working aisle open, a person on foot or a truck entering the aisle cuts power to the bases so the units cannot move. The barrier is reset deliberately — by the reset button or by remote control.
• Interior safety barriers. Longitudinal optic barriers run the full front of the mobile unit on both sides of the base and stop the bases automatically if the beam is broken by an obstruction in the aisle.
• Proximity photocell. Gives a smooth, controlled stop at the pre-programmed aisle spacing so rows land in the same place every time.
• Reset and emergency stops. Reset buttons sit at the end of each aisle; emergency stop buttons in the remote power box stop the moving rows.
• Synchronised drives. Power converters coordinate the motors on a base so the row accelerates and stops smoothly, which also protects motors, wheels and guides over time.

Aisles are opened either automatically by remote control or manually from a switch or control pad. Remote operation matters more than it sounds: an operator who can open the aisle from the forklift seat does not dismount, walk to a panel, walk back and remount for every aisle change, and that is where the throughput cost of a mobile block is either contained or multiplied.

Blocks can also be specified with a parking arrangement that spreads the gaps between rows when the room is not being worked. In refrigerated rooms this is used to improve air circulation during downtime, and where space allows, the resulting gaps can be used for picking individual items from lower levels.

Whatever mode you choose, commissioning, operator training, a written safe-operating procedure and a documented inspection schedule are part of the system — not extras. We include them in the scope we quote.

Refrigerated and freezer storerooms are one of the applications the Movirack literature calls out specifically, and there is a straightforward reason: refrigerated envelope is the most expensive warehouse floor a company owns, so removing standing aisles from inside it is worth more there than almost anywhere else. The brochure also notes that spreading stored pallets through the same conditioned volume changes how the cost of generating cold air is carried per pallet, and that the parking arrangement improves circulation during downtime.

But cold changes the engineering, not just the economics. Component selection and finishes, condensation and frost at the rail line, cabling and control enclosures, floor construction under a freezer slab, and the way operators work in insulated PPE all differ from an ambient room. That is its own subject, so it has its own page.

Cold storage mobile pallet racking

1. Number and length of mobile bases. The base is the machine. Block layout — how many rows travel and how long each one is — sets most of the mechanical scope.
2. Drive and control package. Motors, PLC, power converters, panels, remote control and any optional aisle lighting.
3. Track and installation method. The four methods above are not equivalent in cost. New subfloor, poured topping, channels, and channels with spreader beams each carry different material, labour and schedule.
4. Floor preparation and repair. Levelling, joint treatment, patching and the occasional slab replacement. On retrofits this is the line item that moves most.
5. Rack structure. Upright and beam sizing for your pallet weight and levels, the additional bracing mobile units require, plus decking, guarding and rack protection.
6. Electrical scope. Feeding the block, disconnects, conduit routing, and coordination with existing panels.
7. Environment. Ambient, cooler and freezer specifications are not the same system.
8. Building coordination. Sprinkler layout, lighting, ductwork and clear height all interact with a block that changes where aisles sit.
9. Installation conditions. Working in an occupied building, phased installs, off-hours work and product relocation.
10. Commissioning, training and service. Startup, operator training, spares philosophy and the inspection interval you want to hold.

A mobile block has everything a static rack has to be inspected for, plus a drive system. Rack damage inspection continues exactly as it would on static rack — impact damage to uprights and beams, missing safety locks, loose anchors, out-of-plumb frames. On top of that, the drive motors, gearboxes, carrier rollers and guide wheels, cabling and cable channels, and every safety device need a scheduled functional check.

Rails need something simpler and easier to neglect: they need to stay clean. Debris, damaged pallets, shrink wrap and spilled product in the track are the ordinary cause of rough travel and premature wheel wear. Housekeeping around the block is part of the maintenance plan, not separate from it.

We can quote inspection and service intervals with the system so that adjustment, safety-device testing and wear-part replacement are planned rather than discovered during a peak week.