Modern Russian Machinery and Plant for Production of Autoclaved Aerated Concrete

Worldwide production of cellular concrete has shifted to the production of high-precision cut Autoclaved Aerated Concrete. TMP specialists designed and constructed cutting and molding machinery that is competitive and unique in the engineering development. This machinery can be used for manufacturing of autoclave aerated concrete (AAC) at lime brick plants that have undergone reconstruction, or it can replace outdated cutting machines on AFC producing plants. The current infrastructure can be used effectively including: heat and energy systems, mills, blending machines, batchers, autoclaves, receivers, storage, etc. In a situation when resulting from the rising construction volumes we see a large demand for the equipment for construction industry, this seems to be the most reasonable way for the development of Autoclaved Aerated Concrete production in Russia.

The first project was the reconstruction of CSJC VKSM lime brick production plant in Voronezh, Russia. The second one involved the upgrade from outdated cutting equipment to Autoclaved Aerated Concrete production technology. Recently, the third cutting and molding complex was placed in operation at the JSC Orshastroymaterialy, Republic of Belarus.

Due to it design features, the cutting and molding equipment for production of aerated concrete blocks (Univeral—60) that is used currently by the plants does not allow for geometric precision to comply with modern demands. The complex designed by TMP can replace these outdated cutting machines.

Production Process (Fig. 1):

After the slurry is poured in molds s (1) and cured the green cakes are moved to the mold assembling/disassembling manipulator position (4). The mold (1) is welded into precise geometrical form; it consists of a body frame and a removable side guard, which functions as a hardening tray (2).The manipulator (4) lifts the mold (1) with clamps, moves it to the cutting complex bridge. Then it rotates the mold 90 є and puts it on the cutting cart (6). Special devices open the mold while the tray with cake remains on the cutting cart. The manipulator moves the mold body frame on the return conveyor (14), where it assembles the mold and sets in on the rails to be moved to slurry pouring position.

The tray with block on the cutting cart moves through the side-cutting machine (7) where length of block is formed, and if necessary, finished with the «grove» and «tongue.» After, the block passes through a horizontal cutting machine (8) and a vertical cutting machine (9) where indentations for hand-holds in blocks are made if needed. Then the block is placed on a transport cart (11) fed to the vacuum system (10) for flange removing, and finally moved to the transfer unit operating area.

The transfer unit (12) moves the tray with the block onto the autoclave trolly (13). The autoclave trolly with the block is moved to the autoclave with a transfer bridge (15) where the block is hydrothermally treated. After the treatment, the autoclave cart and the block are moved to the transfer unit operating area (16) where the tray re-stacked and blocks are separated (17). Next, the reclaimer places the blocks on wooden trays, and the blocks are transported to the storage by the take-away conveyor system.

1 — mold; 2 — tray; 3 — mold transfer unit; 4 — molds assembling/disassembling manipulator; 5 — automatic complex for aerated concrete cutting; 6 — cutting cart; 7 — side-cutting machine; 8 — horizontal-cutting machine; 9 — vertical-cutting machine; 10 — vacuum device; 11 — transport cart; 12 — tray stacker on autoclave cart; 13 — autoclave carts; 14 — hardening tray return conveyor system; 15 — carts transfer bridge; 16 — tray stacker on autoclave cart; 17 — block separator; 18 — conveyor for returning hardening trays.

Due to the short length of the cutting strings, the accuracy of the moving tray and flexibility in adjustment of cut speed, this equipment allows to make precise geometric forms of blocks. The side surfaces can be flat or could be made with grove and tongue, which allow for the blocks to lock together without the use of adhesive or vertical joints. Accurate height dimensions (±1mm) enables the adhesive thickness on which the blocks are placed to be 2mm. Installation of precisely dimensioned blocks with grove and tongue does not only speed up the construction process, but lessens the cost. Furthermore, the use of adhesive provides better insulation properties. The cutting complex enables pocket grinding, intended for the comfort of block moving and installation.

Thus, establishing autoclaved aerated concrete manufacturing process could be done by replacing the outdated equipment at the existing facilities, or as an upgrade of lime bricks plants using part of original equipment: mills, blending machines, transport units, batching units, autoclaves, etc., which is less costly and does not require as much time. The price of cutting and molding equipment totals 30—35% from net cost of technological lines.

The aerated concrete blocks equipment includes:

· molds with removable hardening trays

· manipulator for mold assembly and disassembly

· automatic complex for aerated concrete cutting

· track for cart moving

· cutting carriage

· transport cart

· side-cutting machine

· horizontal-cutting machine

· vertical-cutting machine

· vacuum device

· tray stacker and autoclave industrial carts

· autoclave carts

· disassembly device for aerated concrete products

· conveyor for returning hardening trays

· conveyor for finished products

All parts of TMP’s cutting and molding equipment are automatically operated. There is an adjustment mode for the adjustment of mechanisms. Monitors indicating all diagnostic information related to the current complex state are installed on the control panels.

All equipment intended for production of aerated concrete blocks is first assembled and tested on TMP property. It is then disassembled into large components. TMP specialists monitor the assembling process. Equipment for manufacturing aerated concrete blocks is known for its reliability in operation and ease of maintenance. The warranty period is one year. Equipment for autoclaved aerated concrete blocks is very reliable and easily maintained.