Trimming dies are specialized tools used in the cold heading process to trim excess material from a formed metal part, typically a fastener such as a screw or bolt. After the initial forming process, the part may have excess material or flash that needs to be removed to achieve the desired shape and size. Trimming dies are designed to remove this excess material from the part by cutting it away with precision and accuracy.

Trimming dies are typically made from high-strength tool steel or tungsten carbide and are custom-designed to meet the specific requirements of the part being trimmed. They are often used in conjunction with other cold heading dies, such as heading punches and extrusion punches, to produce a finished product that meets the required specifications for size, shape, and thread profile.

The process of using trimming dies involves inserting the part into the cold heading machine and positioning it under the trimming die. The trimming die is then brought down onto the part, cutting away any excess material or flash. This process is repeated until the part is trimmed to the desired shape and size.

Trimming dies play a crucial role in the cold heading process, enabling the production of high-quality, precision-engineered metal parts. They are essential tools in the manufacturing of fasteners and other metal components for various industrial applications.