FAQs

Wet clay and gypsum possess high surface tension and cohesive properties. Stored in mild steel silos, moisture induces rusting, creating a rough surface that anchors cohesive materials. Over time, materials build up, causing bridging (Arching) or rat-holing, which interrupts material feeding into the raw mill.

Mild steels like SS400 or Q355B have low nominal surface hardness (typically ~120 – 170 HBW). When hard Laotian iron ore lump (with a hardness of ~6 Mohs, equivalent to ~400 HBW) falls from conveyor discharge heights, the mechanical kinetic energy gouges the soft metal, leading to plastic deformation, structural tearing, and rapid wear-through within 3 to 4 months.

Yes, GAC backs its turnkey supply-and-installation projects with a formal technical and performance warranty. We provide a 12-month warranty for high-impact and heavy mechanical applications (such as sinter-crusher chutes, coke screens, and skip cars) and a 24-to-36-month warranty for monolithic, erosion-resistant systems (such as Kalcret-lined slag pipes and weld-on Kalocer ceramic chutes).

The steel backing plate must be grit-blasted or mechanically ground to achieve a white-metal finish conforming to the SA 2.5 standard. Following blasting, the surface must be thoroughly degreased using professional-grade solvents (such as Acetone or Lacquer thinner) to remove all traces of grease and dust. Ceramics must be bonded within a few hours of cleaning to prevent surface oxidation.

Dynamic fan impellers rotating at high speeds are highly sensitive to weight distribution. Conventional hardfacing overlays leave a rough, uneven surface that increases aerodynamic drag and causes dynamic imbalance. GAC shields impeller blades with ultra-thin (10mm), lightweight Kalocer high-alumina ceramic tiles bonded with heat-resistant Kalfix epoxy, extending blade service life by 3 to 4 times while keeping the fan perfectly balanced.

Sintered coke is highly abrasive and sharp. Falling from a height of 5m onto vibrating screens, it exerts severe combined sliding wear and dynamic impact, quickly deforming mild steel decks. GAC solves this with a combined lining layout: the sliding screen deck is lined with Kalmetall W100 clad plates (10+10mm, HV 700) to resist abrasive wear, while the fastening bolts are protected with heavy-duty caps fabricated from tough Hardox 500 TUF (15-20mm) to absorb dynamic impacts.

Immediately after troweling, GAC technicians apply Kalcure specialized spray-on curing compound to seal surface moisture and prevent rapid evaporation. Thanks to its fast-curing polymer-silica formulation, Kalcret achieves over 70% of its full compressive strength within 24 to 48 hours, allowing the plant to resume operations quickly.

Per Kalenborn engineering standards, the expanded steel mesh must be welded with a precise 5mm clearance from the steel backing plate. This creates a robust mechanical anchor within the mortar layer to absorb shrinkage stresses. The mesh-anchoring pins must be plug-welded at intervals of 250mm to 300mm to distribute mechanical shear stresses evenly across the 25-30mm lining thickness.

Kalmetall bimetallic cladding contains a high concentration of carbon (5%) and chromium (30%), forming a dense network of chromium carbides that are highly resistant to thermal oxidation. Standard oxy-fuel cutting cannot reach the temperature required to melt these carbides. Cutting must be executed using high-capacity Plasma Arc systems (minimum 150A) or Ultra-High-Pressure Water-Jet systems.

No, GAC utilizes a recessed stud-welding fastening system. Threaded studs are welded to the silo’s steel wall. The Tivar sheets are pre-bored with countersunk holes, secured with recessed locknuts, and sealed with matching Tivar plugs flush with the lining surface. This creates a completely flat, seamless sliding surface with no exposed bolt heads to obstruct material flow or wear out.

GAC lines the silo hopper cones with Tivar 88-2 UHMW-PE sheets (12.7mm thickness). Thanks to its low dynamic friction coefficient (0.08) and near-zero water absorption (<0.1%), Tivar 88-2 prevents wet cohesive materials from bonding to the silo walls, shifting the discharge profile from core flow/funnel flow to smooth, continuous Mass Flow.