Small bugs can lift several times their own weight and they still look slender and delicate. Entering the testing area of Putzmeister gives you the same impression. Arms from concrete pumps are reaching for the stars, or at least up to 60 metres up in the sky. These are the machines making it possible to build high constructions, long tunnels and bridges very efficiently.

The functionality testing is the final step before delivering the new equipment to the customer, who could be found everywhere in the whole wide world. Putzmeister has a strong position on the market for concrete pumps – truck-mounted or stationary.

The more conspicuous a building is, the more likely that concrete pumps were used to realize the dreams of architects and designers.

When you see the concrete pumps working, their capacity seems unnaturally big. From one day to another you could literally experience that a building is growing in front of your eyes.

“And as a matter of fact, it is,” says Jürgen Kronenberg, manager of Public Relations at Putzmeister AG in Aichtal. “In theory the most efficient Putzmeister concrete pumps can distribute the haul from a concrete truck every third minute. Even if it in reality means that the handled volumes are smaller, it says something about the capacity.”

Putzmeister has been on this market since 1956 when Diplom engineer Karl Schlecht founded the company. The first product was a plastery machine that still is on the product program. In a few years Putzmeister will celebrate 50, even though the name is some years younger, the brand Putzmeister was introduced 1963.

The manufacturing of concrete pumps is situated on two plants, in Gründau and Aichtal.

All over the world

“In Aichtal we have R&D as well as final assembly and testing of the equipment,” explains D. –Ing Markus Wolfram, Technisher Leiter Betonverteilermaste. “The plant in Gründau does the major part of the mechanical work, like cutting, bending and weld ing the masts for the concrete pumps. They deliver the units to us and other Puzmeister companies all over the world, where we have final assembly depending on different requirements from the markets.”

Markus Wolfram agrees that there is a similarity between the bugs and the concrete pumps.

“But I would rather say that we use the principals from nature in general to build stronger and with higher quality,” he says, pointing at the bended structures on the boom. “The shape of the connection between a tree and its branch gives unsurpassed strength. Use the same design together with high strength steel and you will probably have a lightweight construction that can live up to all expectations.”

Long experience from high strength steel

Putzmeister has been using high strength steels since more than ten years, which is as long as   SSAB Swedish Steel has been delivering the advanced high strength steels to the company. Today the production is tailor made to get the most out of the Swedish steel. The steel sheets are cut with laser, water or plasma before bending and welding. Most of the welding is done with robots to maintain even and high quality. Tolerances are very low as any kind of failure when the unit is in use could cause severe problems on a construction site. The high strength steel used by Putzmeister is between 3 and 20 millimetre thick. The further out on the boom, the thinner the steel. Markus Wolfram explains the principals. “In general you could say that one kilo on the last part of the boom is as heavy as two kilos on the truck,” he says.

62 metres boom

Most of the concrete pumps that Putzmeister delivers come mounted on trucks. The biggest ones, with 62 metres boom, have six or seven axles and they often need special permits to be used on public roads. There are other concrete pumps made for stationary use, for example on top of extremely high buildings and other places that are out of reach for mobile equipment.

Even though vehicles with concrete pumps look very much alike, there are big differences as they all are specified from customer demands.

“And as each one is more or less unique, an increasing part of our business is to have training with drivers as a part of the delivery,” Jürgen Kronenberg explains. “This education covers driving and working with the concrete pump, but also questions about maintenance.”

This is very important as the life of a concrete pump very much depends on how careful it has been taken car of by its driver.

“I have seen vehicles that look like new, though they were several years old,” Markus Wolfram recalls. “This was during a visit at Putzmeister in the US and it was obvious that this well-conducted vehicle gave the owner good publicity and at the same time the profitability was better thanks to the good condition.

You could describe a mobile concrete pump as a construction with four different elements: the vehicle, the pump, the mast and the tube.

The tube has to be very wear resistant, but still it does not last more than 1 – 2 years. Putzmeister has a tube that is manufactured out of two different steel tubs, the inner tube with high hardness and the outer lining from softer steel. “It is almost impossible to predict how long thetubes will last,” says Jürgen Kronenberg. “You could hardly imagine how different concrete can appear depending on mixture, water, sand, cement etcetera.”

Concrete is heavy

Another important factor is the density of the concrete; it is 2.4 times heavier than water. It does not take a civil engineer to understand the effort on the equipment when the pumps are pushing 1,000 litres a minute through the reinforced tubes.

A visit to the Putzmeister website tells you that the company is involved with a huge amount of the most spectacular buildings in the world – monuments that will live for a very long time. And now you know that Putzmeister are closely connected to those creations in concrete.

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