Video Transcript

The use of aluminum in the automotive industry has increased significantly in recent years. Poor hole quality, frequent tap breakages and chip evacuation issues are all problems when tapping blind holes.

In this film, we will demonstrate proven methods that when applied will help meet your customers' demand for efficiency and help reduce the total cost per hole when tapping. In aluminum cylinder head production, the most commonly used taps are the M6, M8 and M12 series. Many manufacturers use spiral flute taps with radial coolant for through holes and with axial coolant for blind holes. However, this strategy often results in long chips, poor hole quality and tap breakage. Selecting an appropriate tap with the right flute design is critical to a trouble-free tapping operation. Factors such as core thickness, rake and relief angles and land width should be carefully considered.

In order to maintain tap strength and rigidity, we recommend using a straight flute design with axial coolant for blind holes. This results in shorter chips that can be easily evacuated. Good thread quality and process security can be ensured by using a sharp geometry and maximizing the flute space of the tap. A combination of an optimal substrate and coating gives protection against abrasive and adhesive wear, resulting in longer tool life and better surface quality.

To maximize the performance of the tool in high-speed tapping, it is recommended to use a synchronized tapping chuck on CNC machines with synchronized tapping cycles. Oversized threading can be avoided by using a rigid tap holder with micro-float compensation. Thank you for watching. We hope you found this video useful. To learn more about tapping, visit the Sandvik Coromant website.