[News] Automated Shot Blast Solutions for High Value Castings

[tornado]

Increasing process safety, decreasing costs. While today's foundry operations are mostly automated, surface treatment frequently still involves a lot of manual labor resulting in one of the most labour-intensive and costly operations within a foundry.Automated systems tailor-made to the unique requirements of desanding and deburring, as well as overall surface finishing, of raw castings not only significantly reduce costs but also increase process safety.Regardless of how a component is cast, tasks such as desanding, deburring, and surface cleaning are often still carried out manually. Not only are they extremely time consuming and highly labor intensive, but the quality of manual blasting strongly depends on the skills of the person who is blasting resulting in a process that not consistent or documentable. High qual-ity shot blast results are, however, a crucial quality aspect for any foundry product and an important competitive factor.Staying Competitive by Automating the Blast Cleaning ProcessIn the field of post treatment of small to medium-size castings in particular, Rösler Oberflächentechnik GmbH is able to offer solutions that will significantly increase the degree of automation in the fettling operation of a foundry. The benefits are not only limited to the field of large area external shot blasting as targeted desanding and/or deburring of bore holes, channels, vents and undercuts are also possible.The automatic control and monitoring of various parameters of the shot blasting process ensures that all components are treated according to their individual needs at a consistently high quality level. For example the processing intensity can be adjusted by varying the throwing speed of the blast media.The required processing time to achieve consistent shot blasting results is determined by defining the amount of blast media thrown per unit of time and the cycle time can be shortened and throughput rates can be increased by increasing the blast media quantity.An automatic component positioning device guarantees that geometrically complex components in particular are positioned accurately in the blasting chamber. By monitoring the quality and grain size of the blast media, spent abrasive can be continuously separated from the process and replaced with fresh abrasive via a media replenishing system.By registering every single component in the equipment control panel program, the conditions under which the component has been shot blasted can be traced back reliably. The advantages of automated processing of iron, steel and non-ferrous raw castings are such that the cost-savings and quality improvements below can be realized:Improved process safetyUp to 80% less manual workLower labor costHigher throughput ratesLower manufacturing costsRepeatable and documentable shot blasting processesSemi-automatic shot blasting machine for internal desanding: The internal desanding of cylinder heads is a delicate task as channels and side walls can be extremely thin. Special care must be taken to make sure that the shot blasting process does not abrade too much material as well insuring that all residual sand is completely removed.In order to achieve optimum process safety and reduce the amount of costly scrap, MAN, a world-class manufacturer of trucks, replaced their manual shot blasting processes with a Rösler semi-automatic air blast system. The STD 1400-2 x 8 is equipped with high-pressure blast nozzles with the pressure of each blast nozzle being monitored individually. The nozzles are moving via a 3-axis traversing unit which ensures that all channels and vents are reached and cleaned within pre-set cycle times. In addition, a tumbling movement ensures that trapped blast media is removed from the parts. The effective processing time for an 8-cylinder block is two minutes in the Rösler machine compared with 5 minutes for the manual process. After the blast process a 100% inspection takes place. In addition to the achieved consistency of the blast process, the tailor-made Rösler system provided MAN with an 8 times higher productivity resulting in considerably lower cost.Fully automatic shot blasting of the outside and inside areas of components: In order to automatically blast clean both the outside surface, as well as the channels, of small to medium size raw cylinder head castings automatically the Rösler engineering team developed the Complete Desander (RCD) concept.The Complete Desander is a 6-axis robot that takes the component off a transport system and places it into a carousel type shot blasting machine (RWK 6/12-2) consisting of two chambers. While a component surface is blast cleaned by two high-performance blast wheels of the Hurricane type in one chamber, the other chamber is utilized for the unloading and reloading of parts.Throughout the entire processing time the casting in the blast chamber is rotated by a separately driven satellite so that flash and/or sand can be removed thoroughly.Once the shot blast cycle is finished, the handling robot will remove the component and place it into an adjacent air blast cabinet. Connected to this cabinet is a second robot unit which is equipped with a one nozzle pressure blast system.The blasting head of this robot, which is specially sealed to prevent leakage of abrasive, travels along the pattern of the channels in the component to remove burrs and residuals in the bore holes. When the blasting process is finished, the handling robot removes the component from the cabinet, rotates it to remove the blasting media and places it onto the transport system.Compared with “traditional” processing methods where the external areas of components are commonly treated manually using overhead monorail blasting machines and high-pressure wet blasting, this fully automatic solution not only significantly lowers costs but offers high process safety as well. This kind of machine concept can also be designed to process larger castings.Roboblaster - fully-automatic blast cleaning and high flexibility for production lines: The Roboblaster, a combination of a shot blasting unit and a 6-axis robot specially engineered to suit the respective application, can be deployed for different blast cleaning tasks - from deburring and desanding all the way to shotpeening.A Southern German automobile manufacturer utilizes this highly efficient, compact and sound protected blast system to deburr and surface finish bell/gearbox housings made of magnesium in a cycle time of just 26 seconds. In order to handle the components from two parallel pressure die casting lines and place them into the shot blasting unit, the robot is equipped with a double gripper. In the blast housing the bell/gearbox housings are shot blasted by six Hurricane type high-performance blast wheels, two of which are mounted to the rear wall of the cabinet which ensures that the internal areas are blast cleaned efficiently.The Roboblaster operating at an aircraft engine manufacturer is a lot smaller. Its main body is the size of a hand blasting cabinet and very small turbine blades are shot blasted. The shotpeening process, applied here in accordance with the very strict aerospace regulations, significantly increases the fatigue life of the parts.The wire-mesh belt machine: A highly productive and versatile all-round blast cleaning machine. Rösler's wire mesh belt machine, the RDGE, guarantees comprehensive, fully automatic processing of different components with complex geometries in continuous flow operation.By varying the number, power and position of the individual blast wheels, this unit can be adjusted to multiple shot blasting tasks providing high process safety

More... (http://www.aerospace-technology.com/contractors/manufacturing/rosler/press3.html)