In the IGU fabrication workflow, the bottleneck isn't usually the tempering furnace or the robotic sealing line—it's the chaos in between. Sorting and pairing glass lites manually leads to fingerprints on Low-E coatings, edge chips, and production delays. You need a dedicated WIP buffer that moves as fast as your CNC lines. Our Insulated Glass Production Carts optimize the flow from cutting to assembly, ensuring every lite arrives at the washer scratch-free and ready for pairing.
For high-volume Insulated Glass Unit (IGU) manufacturers, the critical pain point is "pairing." You have the outer lite (perhaps 6mm tempered) and the inner lite (perhaps laminated or Low-E) coming off the CNC cutting table or tempering furnace at different times. If you are piling these onto standard A-frames or L-bucks, you are wasting valuable floor space and risking breakage every time a worker shuffles through the stack to find the matching piece.
The Harp Glass Rack (often called a Harp Cart or H-Rack) is engineered specifically for this phase. Unlike static storage, this is a dynamic sorting tool. With numbered slots and high-density dividers, your team can sequence glass output immediately. Slot #1 gets the outer lite, Slot #2 gets the inner lite. When the cart rolls to the washer or assembly line, the components are already paired, eliminating confusion and "search time."
High-visibility numbering on the roller track ensures zero errors during the pairing process.
Architectural glass fabricators often face a specific geometry challenge: long, narrow sidelites or transom windows. On a traditional roller-bottom cart, these pieces are unstable. They lack sufficient base width to stand straight, often leaning precariously or twisting, which puts stress on the glass center.
Our solution is the Full Base Harp Rack design. Instead of relying solely on rollers that might have gaps, we utilize a full steel base with precision-cut slots (lined with HDPE or PVB). This provides a continuous support line along the entire bottom edge of the glass. Whether you are processing a 12-inch wide sidelite or a standard door panel, the glass sits square and secure.
The slightest contact between a metal rack and a Soft-Coat Low-E surface can result in scratches that are invisible until the unit is installed and viewed in direct sunlight—leading to expensive field replacements.
Our racks are built with PVC-cased steel rods (Harp strings). The core is rigid Q235A carbon steel to prevent bending under the weight of heavy laminated sheets, but the contact surface is strictly industrial-grade PVC. Combined with the bottom nylon rollers or HDPE slots, the glass "floats" in a non-abrasive environment. This ensures that the glass leaving the Glass Harp Rack at the washer is in the exact same condition as when it left the cutter.
Moving 2,000+ lbs of glass across a factory floor requires more than just good casters; it requires control. Standard wheel brakes often fail on smooth epoxy floors once momentum builds up, or they are difficult to engage when the rack is fully loaded.
We integrate a Foot-Actuated Lifting Mechanism. This system doesn't just lock the wheel; it lifts the rack slightly onto rigid rubber pads. This effectively anchors the cart to the floor during loading and unloading. When the operator is placing a heavy laminated sheet into the slot, the cart will not "scoot" away—a common cause of back injuries and dropped glass in fabrication plants.
| Feature | Specification | Benefit |
|---|---|---|
| Material | Q235A Carbon Steel (Square Tube) | Handles heavy static and dynamic loads without warping. |
| Divider System | Steel Core with PVC Casing | Rigidity for sorting + Protection for Low-E coatings. |
| Base Options | Nylon Rollers or HDPE/PVB Slots | Rollers for easy sliding; Slots for stability of thin/narrow glass. |
| Casters | Heavy-duty Polyurethane (2 Swivel w/ Brake, 2 Fixed) | Smooth movement over concrete joints; minimal rolling resistance. |
| Assembly | Knock-Down Bolted Structure | Reduces shipping volume by 60%+; easy part replacement. |
Many glass fabricators hesitate to order specialized racks internationally due to high freight costs for bulky items. We solved this with a fully Knock-Down (KD) design. The base, uprights, and harp grids are bolted, not welded into a single massive unit.
This allows us to flat-pack the units. We can fit significantly more racks into a standard shipping container compared to fully welded alternatives. Upon arrival, your maintenance team can assemble them using standard tools. This also means if a forklift driver accidentally damages an upright, you can unbolt and replace just that part, rather than scrapping the entire rack.
1. Can these racks handle heavy laminated glass for security applications?
Yes. Our standard Harp Racks are rated for dynamic loads up to 3,300 lbs (1500 kg). The Q235A steel frame and reinforced base are specifically designed for the weight density of laminated and multi-layer security glass.
2. What is the gap between the harp strings? Can it be customized?
Standard spacing is typically around 1/2" to 3/4" to accommodate standard IG components. However, for IGU manufacturing involving thicker spacers or laminated units, we can customize the slot width to your specific production requirements.
3. We produce Jumbo size glass. Do you have a rack for that?
Yes. While standard carts handle sizes up to 84" x 96", we manufacture custom "Jumbo" Harp Racks designed to handle sheets up to 130" or larger, often used in conjunction with overhead crane loading systems.
4. How do the numbered slots help with IGU production?
The numbering allows the cutting table operator to sequence the glass. Slot 1 = Unit 1 Outer, Slot 2 = Unit 1 Inner. This creates a "First-In-First-Out" (FIFO) logic that prevents the assembly line from stopping to look for missing matching lites.
5. Are the nylon rollers safe for glass edges?
Absolutely. We use high-density industrial nylon. It is hard enough to bear the weight without deforming, but softer than glass to prevent shelling or edge damage during the loading and unloading process.
