Various methods could be used for cleaning of the castings. Some to name are shot-blast in abrasive cleaning, grinding wheels, electric-arc cutoff torches and so on. It is vital that all these must be reviewed for energy management and consumption based on various factors like maintenance of equipment used, process used.
Such review and careful selection allow choosing the right one from the review results. This is essential for achieving system efficiency.
The electro hydraulic cleaning process removes the two major drawbacks associated with cleaning operation carried out by shakeout manual process. In shakeout manual process labor task involved is more and the dust produce from the process is high. These drawbacks are removed completely in the electrohydraulic cleaning process.
In the electrohydraulic cleaning process high-voltage discharge is passed between the castings, which are kept immersed in a tank with water. These immersed electrodes results in producing a shock wave. This shock wave helps in removing the sand from casting.Advantages of Electrohydraulic Cleaning :
The major advantage associated with electrohydraulic cleaning is since dust is removed by the result of shock wave in water the process of dust collection is not required. Also the timing for carrying out the process of electrohydraulic cleaning is less and the whole process gets finished in seconds. The process also has the greatest advantage of using energy efficiently and there by contributes a lot towards energy management.
The process of electrohydraulic cleaning also has an additional advantage apart from efficient utilization of energy. It is that it contributes a lot towards reuse of heat and there by heat management.
This is because the shock wave is produced inside water and as a result the water gets warmed. After the process gets finished heat gets produced in this water and this can be re used efficiently for other process in the foundry.
Thus the process contributes a lot towards energy management and heat management.
Grit blasting uses compressed air for the process of cast cleaning. In the process it is possible to clean the castings to the lowest surface possible.
Though this stand as an advantage the major drawback associated with the process is does not use energy efficiently because compressed air acceleration involves high energy and adds a lot towards cost because of the compressed air cost being on higher side.
For further improvements in efficiency in the cleaning and finishing process in a foundry proper measures for maintenance of casting cleaning equipment and tools must be taken at regular consistent intervals. Some of the process improvement at lower cost would also add a lot in this aspect. Some to name are usage of trimming dies in large usage of non-ferrous castings, usage of hydraulic wedges and so on. Some of the process improvements which would involve higher cost for installation but proves its worth in this area are usage of dry ice pellets of solid carbon dioxide replacing sand or grit blasting to carry out cleaning of permanent moulds.