Control Porosity in Die Casting Easier with Shibaura Machine

ELK GROVE VILLAGE, IL, November 18, 2021 - 

The tiny ​​pockets of air and small voids found in parts that we call porosity can quickly turn into a manufacturer's worst nightmare. Porosity in parts can not only harm a component's structural integrity, but also make it downright dangerous. When producing high quality parts it is imperative to ensure your die casting machine offers capabilities to help reduce porosity during production.

Shibaura Machine die casting equipment’s TOSCAST control system allows manufacturers to easily control the entire process, improving conditions, and therefore reducing porosity. 

How exactly does the machine and TOSCAST control system operate together to reduce porosity in part production? 

Think of turning on a faucet- you have a water tower in your town holding the water, storing energy, and then flowing the water through pipes when you turn the faucet ON. Adjusting the faucet, you can control how quick or slow that water flows out to fill the sink- you are metering out the flow. The meter out function on the TOSCAST control works in a similar manner, controlling the flow of hydraulic fluid with a spool type valve. This allows you to precisely control the speed at which you fill up the die casting cavity, just like how you control streaming water out of your faucet.

Then, similar to you using an air pump filling up a bicycle tire, the TOSCAST gives control of the force and pressure throughout the shot process - squeezing down bubbles without opening up the die itself, due to the machine’s mechanical toggle clamping rigidity. The TOSCAST meter-out servo valve precisely controls the speed.

What does this mean for injection unit performance?

Performance of the injection stop, start, and speed is important in die casting production for complete fill and low porosity. Shibaura Machine’s TOSCAST control system affords manufacturers fast deceleration / acceleration, and high velocity.

• With larger size valves, it means 10 m/sec or 400 in/sec speeds are possible in most models and sizes.
• Since only a small movement of the spool valve is needed you quickly achieve 100G acceleration (that is 0 to 10 m/sec in 10 one thousand of a second)

The TOSCAST control is also straightforward and intuitive. With touch screen capability to easily input and modify the shot settings of the speed and position from the point the ladle pours the molten metal into the cold chamber until the end of shot.

The precision the TOSCAST control offers plays a powerful role in improving injection unit performance and porosity. TOSCAST offers precision control of:

• Slow speed past the cold chamber pour hole
• Maintaining the critical shot speed of the metal to the gate point
• Acceleration with up to 100G to fill the part geometry
• An intensification cylinder to squeeze the metal at a very high pressure

Furthermore, the operator can go in and use additional supporting functions to reduce porosity. 

Paired alongside additional TOSCAST functions, the operator can check and decide what certain areas of the part need porosity reduction. Before the shot ever begins, the TOSCAST can monitor and check the metal temperature, die temperature, and vacuum function. 

What does this all mean for die casting production?

Bottom line, with the TOSCAST control system you don’t need to get a running start at pushing the metal into the die cavity. Slow shot can be used up to the point of metal in the runner and at the inlet gate. The acceleration to the proper and controlled filling speed can be reached quickly, which is important to reduce air entrapment porosity.

Small diameter cold chambers can be used, which have high levels of metal fill and less air. This greatly reduces the volume of air within the cold chamber and die cavity. The ability to use a smaller cold chamber also increases the possible metal pressure within the cavity further reducing the size of remaining voids. As the final fill nears, the acceleration can be reversed by a small movement of the main valve allowing effective braking and preventing flash.

The use of large diameter spool valves allow Shibaura Machine injection units to have very high speeds and very fast acceleration / deceleration rates.

Start Reducing Porosity in Parts Today

Porosity hinders parts ability to properly perform. Whether it is withstanding high temperatures, corrosion resistance, part leakage, or the overall strength- all these are impacted poorly with porosity.

Contact the die casting team at Shibaura Machine to learn more about how the TOSCAST control can help improve porosity control and overall part quality.