A concrete batching plant is a machine that manufactures or produces concrete from its various ingredients. They refer to the plant or equipment used to mix the constituent parts of concrete together. It is produced
A concrete batching plant is a machine that manufactures or produces concrete from its various
ingredients. They refer to the plant or equipment used to mix the constituent parts of concrete
together. It is produced based on various recipes which depend on the relative proportion of its raw
materials (aggregates, cement, water, and admixtures). If the ingredients are not properly proportioned,
the concrete will not achieve the desired strength and the overall durability of the structure also
decreases. Aggregates are stored in large steel or concrete bins having different compartments, while
cement is stored in silos. Admixtures refer to various chemicals that are added to concrete to change its
chemical properties. Water is fed to the mixing area depending on the type of the plant.
Concrete batching plants can be divided into two basic types:
Ready mix plants or dry type concrete batching plant:
All the ingredients except water are added in a transit mixer at the concrete plant. This mixture
is then discharged into a ready-mix truck. Measured water is then added to the mix in the truck
and mixed during transport to the job site, to form concrete for delivery to site.
Central Mix plants:
All the ingredients, including water, are transferred to a mixer and mixed together at a central
location. The final product is then transported to the job site. It is also known as wet type
batching plant. It offers the end user a more consistent product since all the ingredients are
mixed at a central location and is computer-assisted to ensure uniformity of product.
A concrete batching and mixing plant generally consists of the following components:
Material storage system, which is divided into raw material storage part and concrete flow part
Weighing system, which includes weighing parts for aggregates, cement, water and liquid
additives. It is a key component to control the proportion of raw materials and thus affects the
quality of finished products.
Conveying system to convey aggregates, powders and liquids.
Liquid supplying system that consists of parts for water supply and additive supply.
Mixing system. It is the heart of the plant and its main function is to mix the various components
into concrete. It is composed of gearing devices, lubricating devices, water distributing device,
mixing device and discharge systems. There are many types of mixers such as tilt drum, pan,
planetary, single shaft and twin shaft mixers.
Control Room and systems: This room is used for the operation and management of a concrete
batching plant. It is where decisions regarding movement of each part in the plant are made.
The working principle of concrete batching plant is dependent on five primary functions: aggregate
feeding, powder feeding, water, storage and conveyance, and control systems.
The process starts with the feeding of aggregates into individual bins, based on size. These
aggregates are weighed individually, as per the design set in the control panel, and then
transferred to the mixing unit.
Weigh hoppers are located above the mixing unit. They are responsible for weighing and then
transferring the remaining ingredients (cement, water and additives) into the mixing unit.
Cement is transferred to the weigh hopper by means of a screw conveyor. Water is also pumped
up into the weigh hopper (in case of central mix or wet-type plants).
After mixing for a pre-specified time, the contents are discharged into a transit mixer or a
All the above processes are carried out carefully and systematically for specified time frames.
The time frame starting from the weighing of aggregates to the discharge of the ready mix
material is known as a batch time.
The plant is usually run by an operator who uses computers to input all the required
measurements. Various measurements of inputs are transported into the mixer on pressing the
Nowadays, mobile, compact and stationary concrete batching plants are available for construction
purposes. They are selected depending upon the application, project, site condition and customer
preferences. Due to its high degree of mechanization and automation, the productivity of concrete
batching plants is quite high and they also guarantee good quality of produced concrete. They are also
equipped with good environmental protection functions like dust collectors to reduce the amount of
dust generated, and muffler devices to reduce noise pollution.