Motor block blast machine replaces overhead conveyor system in foundry

A new blasting system has increased the capacity for sand removal and cleaning of engine blocks in a foundry. The new engine block blasting system replaces an overhead conveyor system and offers a high degree of automation.

One of Turkey's largest foundries has expanded its capacity for the desanding and cleaning of engine blocks with an innovative engine block blast cleaning system. The decisive factors in the decision for the RMBS 1-6-400-30 shot blast solution developed by Rösler were the high degree of automation of the parts handling and process, the significantly shorter processing time compared to overhead conveyor systems and the lower personnel costs. The new blasting system also impressed with its significantly smaller footprint, as it replaced two existing systems and thus freed up additional production space.

The engine blocks produced by the renowned Turkish foundry in gray and nodular cast iron are used in commercial vehicles as well as in ships. To desand and clean the parts, which measure up to 900 x 330 x 140 mm and weigh a maximum of 237 kilograms, the company, like many foundries, worked with overhead conveyor blasting systems, which required a lot of manpower. In this case, there were two - sand was removed in one and cleaned in the second. However, due to increased production figures, there were repeated blasting bottlenecks, so the decision was made to invest in an additional or alternative blasting system. The company's project managers discussed this task with a total of four system manufacturers, including Rösler Oberflächentechnik GmbH.

In contrast to the other manufacturers, Rösler entered the race right from the start with the innovative and efficient system concept of the RMBS 1-6-400-30 engine block blast machine. Adapted to the requirements of the foundry, the system enables the fully automated processing of one large or several smaller engine blocks in short blasting times. The system has a specially developed manipulator gripper for this purpose. The tongs grip the engine block, which is precisely positioned in the blast chamber by a robot, and clamp it firmly in place. After closing the blasting chamber, the part-specific blasting program starts. The tongs rotate the part under the blasting medium jet. The rotation can be slowed down or interrupted for a defined period of time in order to blast certain areas of the engine blocks more intensively. In order to process several smaller engine blocks in one blasting process, these are placed in a so-called workpiece holding frame, which is then clamped by the tongs and rotated directly under the blast media jet.

Compared to the previous overhead conveyor blast machine, where the parts had to be manually suspended from a hanger for the blasting process, the required blasting result is achieved much faster thanks to the targeted movement of the parts in the blasting area. The time savings are so great that sand removal and cleaning blasting are now carried out in a single process in the engine block blasting system and a noticeable increase in capacity has also been achieved. The previous systems could therefore be completely replaced. It also eliminates the risk of areas to be blasted being shielded by other parts. In addition to the higher productivity and process reliability, the lower personnel costs required were among the deciding factors for the purchase. After all, it is becoming increasingly difficult for foundries to find personnel for labor-intensive work.

The six Gamma 400G-8 HD blast turbines, each with a drive power of 30 kW, contribute to the fast and optimum blasting results. In contrast to classic Gamma turbines, the turbines specially developed for abrasive blasting work in foundries have eight "Y-design" throwing blades instead of six and a tool steel lining. Thanks to this special design, the throwing blades achieve a service life up to three times longer than their classic counterparts. This reduces maintenance requirements and enables correspondingly higher productivity and efficiency. The up to 20 percent higher blasting performance with lower energy consumption ensures maximum effectiveness thanks to the special throwing blade design. In addition, the throwing blades can be used from both sides and can be easily changed using the quick-change system with the turbine installed.

The blasting chamber is also designed for high wear resistance. It is made of robust manganese steel. In addition, it is lined with replaceable plates made of this resistant material and with cast plates in areas subject to particularly high loads. (OM-4/25)