The company Siberian Construction Technologies designs and completes automated factories for polystyrene concrete production. In the design of the lines it is possible to provide delivery of commercial polystyrene concrete mixtures followed by shipment to ready mix trucks. The main conception of these technological lines development is control of quality grade and parameters stability of the products at the stage of designing of processing methods and component analysis of polystyrene concrete mixture in view of their interaction extent, and also development of automation system and quality control at all stages of manufacturing.

Factory includes: 

• Sector of storage, preparation and feeding of raw materials;
• Sector of foaming;
• Mixing sector;
• Sector of moulding;
• Thermal treatment sector;
• Sector of polystyrene concrete mass sawing;
• Storage area for finished product. 
  
  

Automation of technological processes of polystyrene concrete products manufacturing allows not only reduce production costs but also significantly raise stability of its basic properties minimizing the human factor, especially in the process of raw components batching and polystyrene concrete mass sawing.

Sector of storage, preparation and feeding of raw materials

Primary components for the polystyrene concrete mixtures preparation should meet standards and specifications for such materials and provide manufacturing of products with desired properties.  
As binding material for polystyrene concrete production (in accordance with GOST 51263 (polystyrene concrete - TU), portland cement or iron-portland cement of marks no lower than М400,meeting requirements of GOST 10178 are used. If necessary to increase polystyrene concrete strength saving mark by strength it is recommended to use portland cement of mark no lower than М500. For foamed polystyrene production as basic raw material foam (bead) polystyrene of series F, marks F-MS, F-SA, F-SB, manufactured by the company Loyal Chemical Ind. Corp. (PRC) is used, or similar to it. For foamed polystyrene production followed by use in polystyrene concrete production it is better to use bead polystyrene of mark F-SA. When manufacturing polystyrene concrete of grade class В1,0 and less as long as requirements of environmental and fire protection are satisfied it is possible to use polystyrene aggregate which is obtained as a result of foamed polystyrene plates crushing.

1. Acceptance and storage of fine materials (cement, fly ash)

For acceptance and storage of fine materials special bunkers (silos) are used. Volume of such silos is calculated due to minifactory production. Materials are delivered by cement trucks. Cement and fly ash are fed to the silos through cement line with the help of pneumatic concrete placer. The silos are provided with aeration system, filters and vibroactivators.  

   

2. Acceptance and storage of polystyrene

Bags with raw materials are unloaded by electric car and kept on the pallets. Duration of storage of every batch should not exceed three months after its release (according to factory certificate). Storage temperature should be maintained in the range of 10 to 15 ^oС. As required bags with bead polystyrene are opened and it goes to the feed hopper of pre-expander. 

3. Preparation of tempering water

For preparation of tempering water through-type water treatment complex is used. The complex is designed to heat, maintain the desired temperature and pressure batching of water in an amount specified by the operator. Heating and transportation of water to the storage container is made with electric boiler and hydro-circulation system. The operator controls management and regulation of parameters. Batching is carried in a certain volume predetermined by the operator. 

    

Foaming sector

Foaming sector includes: pre-expander, steam generator, dryer for polystyrene granules, pneumatic system, ageing bunkers and control section. Bags with bead polystyrene are opened and raw material goes to the feed hopper of pre-expander. After that with the help of screw feeder polystyrene goes to the pre-expander chamber. Primary pre-foaming of bead polystyrene is effected by hot water steam in the pre-expander chamber. Temperature in the pre-expander chamber must be in the range of +95 to +100°С.

The pre-expander capacity and therefore density of foamed polystyrene depends on speed (intensity) of raw material supply from the feed hopper to the receiving cone of the screw feeder. Drying of primarily pre-expanded granules is carried with the help of warmed-up air in the drying machine. When manufacturing foamed polystyrene, conditioning of pre-expanded polystyrene granules is an obligatory stage. During this stage vacuum formed inside the granules (as a result of their foaming) contributes to diffusion of air into the foamed polystyrene cells. Conditioning takes place in the ageing bunkers at comfort temperature of +16 to +25°С. Secondary or multiply (if necessary) pre-foaming of polystyrene granules is performed in the same way as the primary one.

    

Mixing sector (preparation of polystyrene concrete mixture)

Mixing sector consists of platform, remote control, weigh and volumetric batcher, mixing machine with embedded gerotor pump. Cement and polystyrene granules batchers are installed on the platform. The mixing machine is installed under the batchers. A consumable material feeding is performed by remote control which is served by one person.

With the help of the pump water goes to the mixer. Water is batched with electronic batcher of water which is part of the water treatment complex. Necessary agents are loaded to the tank for chemical admixture solutions preparation. Liquid components are mixed and dispensed according to the program.

Fine materials (cement, fly ash) enter to the weigh hopper with the help of screw feeder, in accordance with the consumption rate for the corresponding average density of polystyrene concrete. Then materials go to the mixer. When all components are loaded the solution is mixed for 3-5 min till it is smooth.

Polystyrene granules from the ageing bunkers with the help of the pneumatic system go to the volumetric measuring hopper where necessary volume is batched. After that granules are fed into the mixing machine.
When the solution is ready, operator switches on the gerotor pump which unloads the mixture from the machine.

 

Moulding sector

Ready polystyrene concrete mixture with the help of the gerotor pump goes through rubber mud channel and proportionally pours into moulds. The mould consists of two parts – pallet and removable and interchangeable edges. The pallet is a four-wheeled cart with a metal frame and underframe from water-resistant plywood. Before pouring the polystyrene concrete mixture the removable edges are lubricated and installed on the pallet.

 

Thermal treatment section

After the moulds are filled with the polystyrene concrete mixture, they are moved to thermal treatment chamber. When the chamber is full, it is tightly closed. Thermal treatment process is performed according to the technical regulations. Using the chamber allows to speed-up the process of stripping strength, as well as to get polystyrene concrete with higher strength properties.  

   

Sector of polystyrene concrete mass sawing 

After thermal treatment the mould with polystyrene concrete mass moves by the rail tracks to the sawing sector. The edges of the mould are removed, and the underframe with mass moves to the cutting set and is fixed with gripper on the railway track. Moving the cutting set saws off blocks of given sizes in vertical and horizontal plane. Set capacity is 4-6 m³ per hour and during one shift (10 hours) it can be 40-60 m³.

The cutting set makes two cuts per one pass аs in vertical both in horizontal plane. Using the mobile moulds with removable edges eliminates use of hoisting mechanisms, which means decrease of materials consumption and material costs reduction.  

   
    

Storage area for finished product

After cutting the ready blocks are put on the pallet and wrapped with wrap tape. The pallets with polystyrene concrete blocks are kept in the storage area for finished product until they pick up 70% strength and moisture max 25%. Storage temperature must be min +15⁰С. The pallets with blocks are put in 2-3 layers. The storage area is calculated due to daily production. 

    

Advantages

Automation of working operations control processes. Electronic control systems of raw materials feed and batching in the mixing sector are used in these production lines. One operator controls the mixing sector functioning. Also only one operator controls functioning of the cutting set in the mass sawing sector.

Permanence of batching. Consumable materials are put to the weigh hopper with strain sensors and balance controller, which allows getting precision weighing. Constant volume of polystyrene granules is provided with the sensor of the volumetric batcher.  

High quality of mixture stirring. Stirring gear consists of two oppositely directed screws. This provides full and high-quality stirring of polystyrene mixture.

High productivity. Provided by the automated system of feeding and batching of raw materials, as well as speed of loading the mixer with water and raw components. The high-capacity cutting set provides high speed of sawing of mass into blocks of given sizes is provided.

Quality of products. The products manufactured by our numerous clients are certified. We invite you to get to know our products and confirm its advantages.