CE Certified Drive In Warehouse Racking Factory & Supplier

In standard selective pallet racking, transverse horizontal beams create rigid portal frames in both axes. Because Drive-In racking requires forklifts to drive inside the bays, intermediate beams cannot be installed along pallet positions. Structural stability is maintained through three critical components:

1. Top Horizontal Portal Beams: Heavy-duty tubular or box beams bridge upright frames across the top of every lane, resisting lateral sway.

2. Overhead Horizontal Bracing: Diagonal cross-bracing along the roof plane of the rack ties all parallel lanes into an interconnected structural box.

3. Rear Vertical X-Bracing: A full-height structural steel diagonal X-bracing truss installed at the back of every dead-end lane prevents longitudinal racking collapse.

Drive-In installations impose combined point-load stresses on the concrete slab from the upright footplates alongside dynamic loads from forklift wheel paths inside the aisles. We recommend a reinforced concrete slab rating of not less than 30 MPa (4,350 PSI) compressive strength, with an absolute minimum slab depth of 180mm to 220mm.

Floor flatness should conform to DIN 18202 Table 3 Group 3 or ASTM E1155 FF 45 / FL 35. Because forklifts operate inside narrow clearance aisles, floor levelness is essential to prevent mast tilt, which could strike pallet support rails at higher elevations.

Under European Standard EN 15620 (Steel Static Storage Systems - Tolerances, Deformations and Clearances), Drive-In configurations require strict operational margins:

• Pallet-to-Upright Frame Clearance: Minimum 75mm on each side between the edge of the load and the upright column face.

• Pallet Rail Overhang: The bottom board of the pallet must bear continuously on the support rail by a minimum of 50mm on each side. A standard 1200mm Euro/ISO pallet typically spans an inside rail opening of 1060mm to 1100mm.

• Vertical Lift Clearance: A minimum of 100mm to 150mm vertical clearance from the top of the pallet load to the bottom of the support rail above it to ensure safe insertion and retrieval.

Drive-In racking is one of the most common high-density choices for cold rooms and blast freezers due to high refrigerated energy costs per cubic meter. However, steel behavior changes under sub-zero temperatures. Low temperatures can cause standard structural steel to transition from ductile to brittle behavior.

Guangzhou Heda Shelves manufactures cold-chain components with high-toughness steel chemistry (such as Q355D or Q355E) tested to maintain Charpy V-notch impact energy at -20°C and -30°C. For surface treatment, we provide hot-dip galvanized finishes (HDG to ISO 1461) or specialized low-temperature electrostatic powder coatings that resist condensation and thermal-shock flaking.

Floor guide rails are continuous structural steel profiles (typically heavy L-angles like L100x75x8mm or C-channels) bolted directly to the slab along both internal base faces of the lane. They provide two major operational advantages:

1. Physical Impact Isolation: They prevent the forklift wheels or chassis from impacting upright posts, reducing collision damage—the primary source of structural failure in Drive-In racks.

2. Increased Operator Throughput: The forklift's external guide rollers engage the rails, keeping the vehicle centered automatically. This eliminates manual steering adjustments and allows operators to drive down deep bays faster and more safely.

While both systems use identical internal cantilever support rails, their access architecture and operational flow differ:

• Drive-In (LIFO): Features a single entry/exit aisle per storage bay. The opposite end is closed off by permanent diagonal vertical X-bracing. Pallets are deposited and retrieved from the same side, requiring a Last-In, First-Out sequence.

• Drive-Through (FIFO): Access aisles are provided at both ends of the lane. Pallets are loaded from the rear aisle and unloaded from the front aisle, creating a true First-In, First-Out inventory flow. Because rear cross-bracing cannot be used in a drive-through lane, the structure requires reinforced overhead bridge towers to maintain frame stability.

To produce an engineered CAD drawing, 3D render, and structural bill of materials, our engineering office requires:

1. Building Dimensions: Usable length, width, and clear ceiling height below overhead trusses, lighting, or fire sprinkler pipes.

2. Architectural Obstructions: Column grid coordinates, expansion joint locations, overhead door dimensions, and emergency exit routes.

3. Pallet Specifications: Width, depth, total overall height including load, and maximum gross weight per pallet position.

4. Material Handling Equipment: Forklift model, overall chassis width, outer turning radius, mast lowered height, and maximum fork lift elevation.