InfraStructures - February 2006 - Schwing S39SX: the Machine for All Construction Site Conditions

Schwing S39SX: the Machine for All Construction Site Conditions

Schwing GmbH

At Bauma 2004, the Schwing S 39 SX truck-mounted concrete pump was presented to the public for the first time. This machine has the longest distribution boom on a 3-axle chassis under 26 t gross weight in the world and the completely new "SX-H" outrigger system which requires smaller floor spaces.

But any machine can look good at an exhibition. Until a concrete pump has been used under the different construction site conditions, it is not possible to get a complete picture of how a machine really performs. One of the first uses to which the Schwing S 39 SX truck-mounted concrete pump was put in Germany was the concreting of a new rain overflow basin at the Kupferzell sewage plant. This involved pumping 400 m3 F3 consistency C35/45 concrete with 0/32 mm aggregate within six hours. The concrete was transported and placed by Kocher-Jagst Transportbeton GmbH & Co. KG, Niedernhall, Germany. This company was the first customer in Germany to use a concrete pump of this type. After several months in practical use, the production shop manager, Franz Holz assessed the situation and gave a positive report. What impressed him in particular was the stability, capacity and cost effectiveness of the S 39 SX. And these features must have impressed other customers because more than 150 units have been dispatched worldwide since the machine was presented 15 months ago.

Because of the SX H system, the machine's multifunctionality can be exploited both outside the city and on city center construction sites which have little space. Setting up possibilities are available to the operator which were previously undreamed of due to the room between the front, space-saving SX bowed outriggers and the rear right-angled telescopic H outriggers. This not only means shorter set-up times but also a floor space which is 80% smaller than that of machines with folding outriggers. The manoeuvrability of the concrete pump unit mounted on an MB Actros 2641 suits practical conditions. Or, as Kocher-Jagst machine operator Gerhard Wirth pointed out: "Wherever a four-axle agitator truck can come in, there is also room for my thirty-niner." Apart from that, special permission from the authorities is not needed since the total length is less than twelve metres.

"Electronic brain" makes work easier for the machine operator
The vector control system is another reason why work on the construction site is simplified for the pump driver. This modular "electronic brain" enables the machine operator to communicate with his Schwing concrete pump. He can call up operating data and record machine status data at any time. A plain text menu driven graphics display is provided to make things even easier. Since the vector control system can be extended, the control platform can take additional systems with new functions.

End hose stop valve prevents concrete overrun
Kocher-Jagst is one of the first customers who has retrofitted their existing Schwing KVM 34 X and KVM 24-4 H concrete pumps with concrete stop valves. Thus, it has been taken for granted that the new machine would also be fitted with this pneumatic valve. The valve acts on the end hose from the outside and holds back the concrete in the pipeline. For the machine operator, this is a great advantage when slewing over previously concreted and floated surfaces since the construction site, machine and surroundings are kept clean and free of mess. The valve, which is synchronized with the concrete pump, responds directly to the respective commands from the remote control system. "Stop pump" results in immediate closure of the valve and prevents concrete after-run or idling of the delivery pipe, which normally takes place when the pump is interrupted in the area of the front jib. Thus, the boom and end hose movements which would otherwise occur on restarting the pump are avoided. Instead, the working height above the surface of the concrete is maintained. This saves the machine operator from having to make tiresome corrections by counter control and makes concreting stress free.

Source: Schwing GmbH