ISO40 is a standard for the design of a tool interface with steep-angle taper and holding bolts for tool machines, such as CNC machining centers.

Features

The steep-angle taper shank has no self-locking and thus, provides the most important requirement for an automatic tool change. Furthermore, this is allowed because of the bolt located on its top.

ISO40 has a larger contact area and thus, there are higher clamping forces than for ISO30. Therefore, this system is primarily used in machines for heavy milling processes. Due to the larger mass, ISO40 is rather unsuitable for machining at high speeds.

Since the mid-2000s, the steep-angle taper is hardly used for new machines, because it was replaced by the hollow shaft taper (HSK-F63).

Alternative terms

• ISO 40
• Steep-angle taper
• Steep-angle taper holder
• SK 40
• SK40