The Wheelabrator Technology Centre in Metelen, Germany, has delivered its largest ever combined shot blast machine to Liebherr Container Cranes Ltd in Killarney, Ireland.
Challenges
Taken in operation in 2013, the new machine blast cleans individual crane components weighing up to 52t and with dimensions of up to 52m length, 3.5m width, and 4.2m height.
Before investing in this new machine, the huge workpieces were blasted manually by an operator in a phone-box-size cabin that moved along the longitudinal axis of the part. The work was physically demanding, and it took between 8 and 12 hours and several operators to manually airblast individual crane components.
Solution
The new equipment has been designed as a combined pass-through monorail shot blast machine, is 36m long, 8m wide and tall, and split in two along the axis of transport.
In Chamber 1, 24 powerful TITAN blast wheels are arranged along two intersecting circles. In Chamber 2, parts then pass through a touch-up area for manual airblasting and abrasive removal.
Lars Südfels, Product Manager at Wheelabrator in Metelen, explains: “Despite the size of the machine, the devil was very much in the detail. To allow the transport crane hook to pass through, there’s a slit in the roof along the full length of the machine, and due to their size, the workpieces are never fully enclosed within the blast chamber. Rubber lamellas and brushes as well as a clever door system were necessary to seal the chamber as tightly as possible.”
Result
The switch from manual airblast to automated wheelblast means processing times are now down to 5 hours per part – a reduction of between 35% and 60% compared to the previous process.
The working environment for operators on the line has also improved drastically, with a touch-up area built for ease of access and an automated wheelblast chamber looking after the heavy-duty element of the task.
Christian Boscher at Liebherr Container Cranes Ltd said: “We were convinced that our relatively simply-shaped and extraordinarily large components were ideally suited to wheelblasting. Together with Wheelabrator and over a period of 2 years, we developed a customised concept, which was then realised and put into operation in May 2013.
“The new shotblast machine has revolutionised our operations here in Killarney and is the ideal extension to our existing manual airblast hall. Due to the aggressive nature of the abrasive material, a quarterly service visit has been agreed with Wheelabrator in order to guarantee a long life time of the installed machinery.”