Steel-Tube-Reinforced Chuan-Character Grid Pallet Mold — Product Introduction (Motek Pallet Mold Series)
Steel-Tube-Reinforced Chuan-Character Grid Pallet Mold — Product Introduction (Motek Pallet Mold Series)
Product Positioning
Motek introduces dedicated injection molds for steel-tube-reinforced Chuan-character grid plastic pallets. Unlike standard Chuan pallets, these molds integrate internal steel tubes directly into the forming surface—the tubes serve a dual function: they shape the pallet’s internal channel geometry during injection, and their metal conductivity accelerates cooling in thick-section transition zones to suppress warpage caused by uneven shrinkage. The resulting pallets deliver upgraded rack load capacity without increasing plastic wall thickness, making them suitable for automated storage and retrieval systems (AS/RS), high-bay racking, and heavy-duty logistics where standard plastic pallets fall short. The core challenges in mold development lie in anti-eccentric core-pulling for steel tube positioning, synchronized cooling of steel-to-plastic interfaces, and rack-load-grade structural reinforcement at tube channel regions.
Core Specifications
| Item | Specification |
|---|---|
| Applicable Plastics | HDPE / PP (high-rigidity grades; HDPE commonly used for tube-reinforced pallets) |
| Mold Material | P20 / 718H for cavity and core; 2738 for steel-tube core-pulling components; 2316 / H718 for sliders and interlocks |
| Number of Cavities | 1×1 (single cavity for large pallets) |
| Mold Life | 500,000–1,000,000 shots (depending on steel selection) |
| Cycle Time | Dependent on pallet size and cooling design; steel tubes act as internal cooling conductors to shorten cycles |
| Injection Machine | 1,600T–2,700T (depending on pallet dimensions) |
| Runner System | Hot runner (typically 20–24 points for 1200×1000mm class; balanced filling of grid and Chuan runner zones) |
| Steel Tube Configuration | Top deck: typically 4–6 tubes; Legs: typically 4–6 tubes (configurable per load grade) |
| Demolding Method | Straight ejector pins + trapezoidal angled lifter (for central groove) + steel-tube core-pulling synchronized with ejection |
Product Features
Dual-Function Steel Tube Integration: Forming and Cooling.
Motek positions internal steel tubes within placement slots that pass through the forming surface. During injection, the tubes shape the pallet’s internal channel surfaces; simultaneously, the metal tubes conduct heat away from the mid-section of the wide, thin pallet body—precisely where cooling lag causes warpage in standard molds. The result is flatter pallets with reduced post-demolding deformation, without extending cycle time.
Anti-Eccentric Core-Pulling for Steel Tube Positioning.
Steel tubes must retract cleanly before ejection without shifting laterally. Motek adopts a horizontal displacement drive mechanism with guided slide blocks: tubes are seated in placement slots, connected to lateral displacement blocks driven by cylinders, with the slide block cross-section matching an I-shaped guide slot to prevent eccentric movement during core-pulling. This ensures tube channels remain straight and aligned, and the steel tubes release without scoring the plastic channel walls.
Rack-Load Structural Reinforcement at Tube Channel Regions.
The steel tubes transform the Chuan runner from a purely plastic beam into a composite steel-plastic load path. Motek reinforces the plastic surrounding tube channels with localized wall thickness and rib transitions, ensuring the steel-plastic interface does not become a stress concentration point under rack loading. Mold flow analysis verifies filling completeness around tube seating features, preventing weld lines or gas traps at the steel-plastic boundary.
Load Grade Flexibility Through Tube Count Configuration.
The same mold platform can accommodate different steel tube counts to produce pallets of varying rack load grades. Reference industry data: a Chuan grid pallet with 8 steel tubes typically achieves approximately 1.0T rack load; with 12 steel tubes, rack load can reach approximately 1.5T. Motek configures tube channel positions and quantities during mold design based on the customer’s target load grade, avoiding the need for separate molds for each grade.
Four-Side Slider Core-Pulling with Angled Lifter Demolding.
The Chuan grid structure creates undercuts on all four sides requiring core-pulling. Motek references industry-proven configurations: large sliders with hydraulic cylinders for top and operator-side undercuts, angled guide pin + large slider for bottom-side undercuts, and a cross-auxiliary-rod angled lifter for internal undercuts. The central longitudinal groove between Chuan runners is released via trapezoidal angled lifters that apply lateral separation force before straight ejection, preventing scoring at the straight parting line.
Cooling System Coordinated with Steel Tube Thermal Path.
Beyond the tubes’ inherent cooling effect, Motek designs zoned water circuits covering the deck grid area and Chuan runner undersides separately. The steel tubes act as internal heat sinks, while mold-side cooling manages the plastic skin. This dual cooling approach is particularly effective for the thick Chuan runner sections, where standard cooling alone would leave hot cores that cause sink marks or warpage.
Mold Outer Dimensions Reference
| Pallet Specification / Configuration | Mold Outer Dimensions (mm) | Hot Runner | Source Type |
|---|---|---|---|
| 1210 Chuan steel-tube pallet (1200×1000×150mm; 6 tubes top / 4 tubes bottom) | 1640×1640×1170 | 24-point | Mold maker |
| 1140 grid Chuan pallet (1140×800×155mm) | 1520×1450×1033 | 20-point | Mold maker |
Applications
Motek steel-tube-reinforced Chuan-character grid pallet molds are suitable for:
- AS/RS high-bay racking pallets requiring rack load ≥1.0T
- Cold-chain and freezer warehouse pallets (steel tubes add rigidity at low temperatures)
- Export and container transport pallets requiring dimensional stability
- Heavy-duty warehousing pallets with steel tube reinforcement for rack storage
- Standard Chuan grid pallets (1200×1000mm, 1200×800mm, 1100×1100mm class) upgraded to rack-load grades
Service Process
After the customer provides 3D product drawings, target rack load grade, steel tube configuration (quantity and placement: deck/legs), and injection machine specifications, Motek completes mold flow analysis (including tube channel filling, steel-plastic interface cooling, and rack load-oriented structural verification) and mold structure confirmation; cavity steel, tube core-pulling components (2738), and hot runner systems are procured according to agreed specifications; progress and key milestones are regularly reported during processing. During trial molding, emphasis is placed on verifying steel tube insertion and retraction smoothness, tube channel dimensional accuracy, pallet flatness, and rack load performance, with samples and inspection reports provided. Before shipment, molds undergo anti-rust treatment and action testing, with water circuit diagrams, hot runner wiring diagrams, steel tube core-pulling sequence documentation, consumable parts lists, and maintenance instructions provided. Technical support is available during the warranty period, with lifetime maintenance consultation.
Motek — From standard Chuan pallets to steel-tube-reinforced rack-grade pallets, providing reliable mold solutions for high-bay warehousing and heavy-duty logistics.
