Reduce Porosity with Shibaura Machine’s Advanced Die Casting Shot Control

ELK GROVE VILLAGE, IL, February 26, 2022 -

Porosity in die casting can not only affect the esthetic of castings, but also impact the structural integrity and functionality of the casting- something manufacturers want to prevent, especially when producing high-liability parts. While it is impossible to eliminate porosity in die casting, with best practices and superior equipment, it can be greatly reduced.

Gas porosity, which is air bubbles trapped inside of a casting as it solidifies, can be greatly reduced if the operator has precise control of the shot cycle. The TOSCAST control on Shibaura Machine Company, America’s die casting equipment allows operators the ability to select position, speed, and pressure of the shot to produce a capable process reducing porosity time after time. By focusing on the shot feedback the TOSCAST helps guarantee the appropriate velocity during the fill phase and adequate amount of force required throughout the casting cycle. 

Controlling the Shot to Reduce Porosity

When you are able to control the points in the program of the shot cycle as a whole it is much easier to achieve reduced porosity. This is done by not inducing additional gas or air into the molten metal throughout the process and at the critical slow shot speed, accelerating to the fast shot speed that correctly provides the proper flow pattern. Finally, at the end of the shot stroke the process reduces the size of porosity with the intensification phase.

Shibaura Machine’s TOSCAST controller allows for complete control and programmability throughout the entire die casting shot process. The advanced system is designed with two separate cylinders and a hydraulic servo meter out system. Based on the feedback the control receives it is able to determine and then make instantaneous adjustments to the speed and pressure. 

The TOSCAST allows the operator to precisely control the speed and program how the molten material flows. From the start, using a slow speed past the cold chamber pour hole, the ability to increase speed past the fill of biscuit and runners, and exponentially increase speed once past that point to fill the geometry. The intensification phase then squeezes the metal at a very high, controlled pressure.

With super high speed injection control it not only reduces porosity, but shortens fill time and improves the internal quality by compressing porosities. The state of pressurizing is controlled from the end of the cavity fill through solidification. These automatic adjustments of pressure, flow rate, or timing make for ideal porosity reduction. The intensification phase starting point can be controlled by position, back pressure increase, or shot speed reduction.

Compared with conventional position based start controllers, the TOSCAST control was developed to start intensification at the same timing, even with ladling volume variation. 

Learn More

The faster you are able to go in and control the casting process, the better porosity reduction. The TOSCAST control brings together the ability to program and control your shot in order to do just that. As a result, even the most complex part geometry is repeatable with reduced porosity.  

Contact the Shibaura Machine Company, America's Die Casting team to learn more about how the TOSCAST control can help improve conditions and repeatability.

• Phone: (888) 593-1616
• Email: dc-sales@shibaura-machine.com