How do Concrete Pumps Work?

May 23, 2013

A concrete pump is a piece of apparatus designed to simplify the process of moving liquid concrete from one place to another. They have become a mainstay of any application requiring large volumes of concrete, and replace the old method of shifting concrete by manual labour alone.

Broadly speaking, there are two main types of concrete pump: boom-mounted concrete pumps, and line concrete pumps. Boom-mounted concrete pumps are attached to a large computer controlled boom which is often mounted on a truck or other large vehicle. Concrete can then be pumped to a site specified by the computer. This type of pump is popular in the construction of large buildings and in applications where a huge volume of concrete must be distributed in very little time. By contrast, line concrete pumps are often mounted onto a vehicle bed, and not attached by a mechanical boom. When using pumps of this type, concrete must be dissipated by connecting several lengths of large diameter hose to the pump, resulting in much lower output rates than their boom-mounted counterparts. For this reason, line pumps are often used for much smaller scale projects, such as small residential renovations.

Several common high-density solid pumps are in use today, each to a varying degree depending on the application due to the unique set of conditions under which each pump is effective. Some of the various high-density solid pumps available include centrifugal pumps, diaphragm pumps, eccentric screw pumps, peristaltic pumps and piston pumps. Concrete poses a number of unique problems to engineers as it is incredibly dense, highly abrasive, often contains a solid component, and will solidify rapidly if allowed to remain static. For this reason, piston pumps, which are capable of generating huge amounts of pressure, are the most commonly used high-density solid pumps for pumping concrete. There are four main types of piston pump available, and are described briefly in the list below:

Piston pump with transfer tube – a two cylinder pump which has an S-shaped transfer tube designed to move between the pump cylinders in a synchronised way.

Piston pump with seat valves – a two cylinder pump consisting of four seat valves arranged to coordinate the intake of fluid from the hopper with its expulsion via the output line.

Ball-valve pump – a two cylinder pump containing a number of ball valves which regulate the flow of material in response to pressure changes when each pump cylinder is activated.

Single cylinder pump – these pumps usually rely on a single valve to prevent backflow of the pumped materials during the operation of the pump.

The benefits of a computer controlled system to accurately dispense precise volumes of concrete to specific locations cannot be overstated. The development of the boom operated concrete pump has vastly reduced the need for labourers dispensing large amounts of concrete by hand with shovels and wheelbarrows, and has subsequently slashed the construction time required for most projects.

The perils of working with high volumes of liquid concrete on a high rise building are obvious, but boom operated concrete pumps provide a safe alternative to employing manual labourers to work in a dangerous way. With this significant increase in safety and reduction in labour costs, the overall costs of large building projects will also be reduced.

Concrete pumps have revolutionised the building trade, allowing projects involving copious volumes of concrete to be completed quickly and accurately, while the safety of the workers remains of paramount concern.