Carbide Cold Extrusion Dies: Review the Entry and Sizing Land
For a tungsten carbide cold extrusion die, send the incoming preform and the part immediately after the extrusion station. A finished bolt drawing can identify the final shank diameter, but the two station drawings show what the insert must actually reduce, where the shoulder forms and which features still change downstream.
Identify the entry and the sizing land
In forward cold extrusion, the punch drives material through a smaller opening. The entry transition guides material into the reduction, and the land is the short working section at the outlet size. Specify both on the die drawing, together with the relief and axial reference. Two inserts can share a nominal outlet diameter while having different working profiles.
In an instrumented study of AA1100 aluminium, Tiernan and colleagues examined the effects of reduction ratio, entry angle and land on extrusion force. The study identifies variables worth reviewing. Choose geometry for the actual steel, lubrication, press and station, using application-specific engineering evidence.
Put the station information in the quote
| Information | What to send |
|---|---|
| Incoming preform | Drawing revision, measured incoming section, material condition and preparation. |
| Outgoing shape | Required reduced diameter and length, shoulder geometry and measurement locations immediately after extrusion. |
| Insert geometry | Entry profile, land, relief and the faces used as axial references. Identify dimensions copied from a worn sample separately. |
| Assembly scope | Holder and support drawings, mating punch, and the components that will be reused. |
| Trial evidence | Traceable preforms and extruded samples, dimensional results and, where available, machine load records tied to the same setup. |
Jungu's custom carbide die cores and matched core and punch sets illustrate two different quote scopes. Use the forming sequence guide when the station boundaries still need to be defined.
Measure the output before the next operation
In a replacement trial, measure the reduced section at the agreed points and note where surface marks start relative to the shoulder. Keep the sample ID linked to the insert revision, preform lot and lubricant condition. If the same setup is used for comparison, record any unavoidable differences. Diameter drift, marks and increased load are separate observations. Review them alongside the working profile and assembly before assigning a cause.
Can a worn insert be used as the master?
Use it to identify the assembly and map wear. Agree the working dimensions from a controlled drawing or accepted part and review any gaps with the toolmaker before manufacture.
Send the two station drawings and the insert section to Jungu for a cold extrusion tooling review.