Adding storage capacity in a sheet metal warehouse usually means one of three things: lease more floor space, stack sheets higher on the floor with growing safety risk, or install fixed racking that locks you into a layout you may outgrow. Herochu’s modular forklift rack system takes the fourth path—bolt-together frames that expand bay by bay without structural rework.

A modular system starts with one standalone unit. The base frame carries six storage tiers with 300 mm clear spacing between levels, each rated for 3,000 kg on the narrower models and 5,000 kg on the HC-F4020-65 and HC-F6020-65 wide-format racks. The column profile uses a closed box section rather than open C-channel, which gives uniform buckling resistance around both axes and simplifies the bolted connection detail between adjacent bays. When a shop needs a second bay, the shared upright column between units receives extension brackets on both faces—no new columns, no extra floor anchors. Three bays become four the same way. Ten become twelve.

This additive architecture matters for shops with seasonal volume swings. A fabricator processing agricultural equipment panels might run three bays through harvest season and scale back to one during winter maintenance months. Because each bay functions as an independent structural module, removing one does not compromise the stability of the remaining units. Base plates bolt to the floor with M16 chemical anchors rated for 12 kN shear per point; columns brace to each other through horizontal tie bars at the top tier. The result is a frame that resists racking loads from forklift impact without relying on the mass of adjacent bays for stability.

The arm design is where modular thinking gets practical. Each arm bolts to the column web through a bracket with three M20 bolts on a 50 mm vertical pitch. An operator with a torque wrench can reposition eight arms across one bay in about twenty minutes. If next quarter’s production run switches from 1,500 mm wide stainless sheets to 2,000 mm aluminum, the arm spacing adjusts to match without cutting steel or welding on site. Herochu ships extra arm sets as bolt-on kits so a single rack frame can be reconfigured for multiple material formats across its service life.

On the material side, Q235B structural steel with a minimum yield strength of 235 MPa forms every load-bearing component. The dual-beam crossbar under each storage arm provides a secondary load path: even if one beam sustains localized damage from a fork strike, the parallel beam carries the rated load independently to the column. Cross-bracing between the two beams stiffens the assembly against torsion, keeping arm tips parallel within ±2 mm across the full 2,000 mm width of the largest model.

Surface treatment follows the same protocol across every modular component: shot blasting to remove mill scale, zinc-rich epoxy primer applied at 40–60 µm, and polyester powder topcoat cured at 200 °C. The finish holds up under the thermal cycling common in unheated warehouse bays, where winter condensation can accelerate corrosion on untreated edges. Bolt holes receive a secondary brush coat of cold-galvanizing compound during assembly to protect the exposed steel inside each connection.

Forklift compatibility spans the four most common lift truck classes. The removable arm channels provide a clear fork entry path 180 mm wide and 80 mm high, accommodating fork sections from 100 × 40 mm to 150 × 60 mm. Because the arms sit on both sides of each tier, the rack works equally well with counterbalance trucks approaching from the front aisle and reach trucks working from the rear. One rack design serves multiple forklift fleets—no adapter brackets, no modified tines.

Lead time for modular expansion bays is shorter than the initial system because the column and arm tooling stays set up after the first production run. Herochu maintains a buffer stock of standard-length arms and column sections, cutting custom lengths to order for non-standard sheet dimensions. Each shipment includes a bay-specific assembly drawing keyed to the original installation layout so expansion bays align with existing anchor patterns and aisle geometry.