With nearly 100,000 employees worldwide, Caterpillar achieved a total sales and revenue of 41,7 billion USD in 2020.
In 1981, Caterpillar purchased the first igm welding robot for the welding of hydraulic excavators, followed by 22 igm systems for Caterpillar in France, USA and Belgium in the 1980ies.
Since 40 years, igm and Caterpillar connects a fruitful and close co-operation, with over 250 igm welding robots successfully delivered to 18 Caterpillar facilities on three continents.
The world largest Caterpillar factory for excavators is located in the city of Xuzhou, P.R. China, where around 100 igm welding robot arms are welding CAT excavator series 312 up to 390.
As per Caterpillar Xuzhou Ltd. statement, the efficiency of a FMS line is about 30% higher compared to stand-alone welding robot systems with manual loading and unloading of the workpiece.
OUTLINE PARAMETERS OF THE EXCAVATOR BOOM FMS LINE
- All igm robots are equipped with TWIN tandem welding process
- Two welding robot arms are mounted on rotating vertical tracks with are moving on a floor track.
- To ensure the gravity welding positon at the boom butt joints, the boom workpieces are tilted so that the butt joint can reach horizontal welding position.
TWIN TANDEM HIGH PERFORMANCE WELDING TECHNOLOGY APPLIED
To ensure constant high welding quality at maximum deposit rate, a TPSi 500 / TPS 5000 TWIN digital inverter welding power source from the Austrian based Fronius International GmbH is used at the igm robots (www.fronius.com)
This means, four arcs are simultaneously welding one excavator boom workpiece.
As a general procedure at Caterpillar construction machinery factories, all cut steel plates must undergo a shot-blasting process, before the tack-welding process begins.
igm always highly recommend that, since a clean workpiece surface will ensure a stable arc so that the welding robots can run without any process-related interruption.
The complete robotic welding workshop is equipped with a central fume extraction piping system and a centrally located dust filter system with automatic self-cleaning filter cartridges.
HIGH-END ROBOT SENSOR TECHNOLOGY
To ensure proper detection and measurement of the gap at the joints, especially the butt joints, each igm welding robot system is equipped an igm laser scanner, type iLS-C, to detect perfectly the precise location of the joint and then adapt the welding parameters accordingly.
AUTOMATIC LOGISITCS ENSURE SHORTEST TACT TIME
A rail-guided vehicle (RGV) will automatically pick up the excavator boom workpieces from a neighbouring tack-welding workshop and deliver the workpieces to the FMS workshop and load it automatically to the igm welding robot systems.
At the end of the FMS line, the finished the excavator boom workpieces will be delivered by the RGV to the unloading stations.
As a "preferred supplier of welding robot systems" to Caterpillar igm is proud, to support Caterpillar in their pursuit, to deliver premium machines of highest quality.