The Process of Manufacturing Concrete Blocks

Concrete block is a primary building material. Many different raw materials go into a block making machine like a mixture of cement, gravel, water and sand.

Concrete Blocks Manufacturing Process

Concrete block making machines manufacturing concrete blocks using the steps:

  • Mixing:
Sand and gravel are transferred into storage bins by making use of a conveyor belt. Portland cement storage usually involves large vertical silos; this protects it from moisture. Production start with the necessary amount of raw material (sand, gravel & cement) being transferred by gravity or using a mechanical structure into a weigh batcher (this ensures correct measure of each material).

A stationary mixer blends the mixture for several minutes. There are two types of mixers, a planetary mixer and a pan mixer. Once blending is over, water is added to a mixer. However, temperature of the water does matter, hence if extreme weather is a factor, they may be need to make use of a chiller or a heater. This is mixed for 6 to 8 minutes and can also include use of admixture chemicals or coloring pigments.
  • Moulding:
Once this is mixed it is dumped into an inclined concrete block conveyor and transported in an elevated hoper. Mixing cycle begins again after is transferred. There is a regulated flow of concrete into another hopper. Concrete is then forced into molds in block machine which consists of an outer mold box that contains several mold liners.
Outer shape of the block and inner shape of the block cavities is determined by the liners. Compact blocks are placed into a flat steel pallet and then onto a chain conveyor which pass under a rotating brush to remove loose material on it.
  • Curing:
Pallets of blocks are conveyed to an automated stacker and placed on a curing rack. Every rack has capacity to hold hundreds of blocks. Once rack is full a set of rails is formed for moving into a curing kiln. A kiln has capacity to hold several racks and is usually a low-pressure steam kiln. Blocks remain in kiln for up to three hours at room temperature till they harden.
Curing process takes up to 24 hours where steam is gradually introduced to increase the temperature. Once a set temperature is reached the steam is shut off and the blocks are then soak in the heat and moist air. Once done there is the process to dry them by raising the temperature of the kiln.
  • Cubing:
The racks of cured blocks are rolled out of the kiln and pallets of blocks are unstacked to be placed on a chain conveyor. These are later pushed off a steel pallet and the empty pallets are fed back to the block machine to receive a new set of molded blocks.
The blocks can split-face ones; if so, the process is to mold two blocks together and once cured the pass through a splitter to fracture them and form a rough stone like texture on one side. A cuber aligns every block and then stacks them into a cube three blocks across by six blocks deep by three to four blocks high. They are then carried outside with a forklift to place them in storage.

Types of concrete equipment

Concrete equipment includes concrete batching plant which are useful to make concrete, concrete bucket that is also used to make concrete mixture, concrete conveyor usually used to transfer gravel, concrete crusher used to crush big rocks pieces, concrete cutting machine which is an abrasive tool, concrete mixer to mix elements to create concrete, etc.