1.AAC Raw Materials Mixing and Mould Casting

Put the sand or fly-ash with water into a ball mill to produce sand slurry. Other dry materials (lime, cement, gypsum & additives) are transported to the silos located in the mixing tower. After mixing 3~4mins, using automatic scale system to do with the aluminum powder for maximum safety and dosing precision and then continue mixing 40s. Once weighed and dosed, the mixer ensures perfectly homogeneous distribution of raw materials in the mix. Once using the pouring mixer to cast the slurry into the freshly mould cleaned and oiled, the mixer is vibrated to eliminate air pockets to ensure the quality of end products.The whole cycle is 5~7min.

2. Reinforcement for panel( this step only for panel)

For the panel production line, a reinforcement station is installed. Before introducing the steel reinforcement in the mix, an assembled steel mesh (for partition panels) or ready cage (for reinforced panels and elements) is dipped into anti-corrosion treatment. After a mix is poured into a mould the reinforcement is immediately inserted into a mould. Precise AAC formula design and control over the cake rising process are especially important in panel production.
 
 The greatest advantage of AAC panel production in the Keda system is that it realize the automatic welding system for wire-mesh cages of panels without  manual operations for welding work, the special circulatory system of saddle base and automatic packing system can reduce handling, cake cracks and other damages (mainly sticking) the element can suffer during the production process and also can save the plant area and labor costs . 

3.Cake Cutting System and Autoclaved Curing

After  that, put the mould box into the curing room with 40～70℃. After 2-3 hours curing,the blocks become solid, using our special de-moulding crane to separates the cake from the mould and put the cake onto ferry car after 90 degree overturning to transport cutting zone. The cutting frame is made with oscillating and pneumatically spanned steel wires resulting in a precise cut.  A recent innovation is design of sloping cross cutting machinery with strength steel wire fixed on the sloping main beams  which can avoid the gravity cracking and realize the minimum cutting size of 50mm. After vertical cutting & cross cutting the cake turns into blocks (L ± 2mm ~ W ± 1mm ~ H ±1mm) 100% of the rest material is mixed with water and used in the next cycle.

The curing car transports the cakes into autoclave with temperature 200℃ and steam pressure 1.2MPa, autoclaving cycle is 11H. The tail steam of the autoclave will be recycled into other autoclaves and/or to pre-curing zone by pipe for completely utilization. 

4. Automatic Packing System
 

In the unloading area an automatic system takes the complete white cake and one-by-one transfers it from the frame onto the pallet table. Elements are then automatically placed on the pallets and transported by a conveyor system to the quality inspection and sorting place. After this station the pallets are ready for final packaging e.g. stretch hood and eventually strapping.
 
In a similar manner, reinforced wall, floor, roof panels and lintels can be packed and strapped automatically or manually. Keda plants can have different packing line designs depending on the sales market.