Short answer: Extruded holes in akụkụ e kụrụ akara increase thread engagement by forming a collar from the mpempe ígwè. They can support thread forming, tapping, or fastener assembly when the sheet is too thin for a plain tapped hole. The RFQ should define thread size, material, thickness, load direction, torque, plating, and inspection method.
Threaded features in akụkụ e kụrụ akara are easy to underestimate. A drawing may show a thread callout, but the onye na-ebubata still needs to know whether the feature should be tapped, thread formed, extruded and tapped, fitted with a clinch nut, or welded with a projection nut. Each route changes tooling, secondary operations, plating sequence, inspection, and risk.
This page connects with the punched holes and slots guide, clinching and insertion guide, projection weld nut inspection guide, and secondary operations guide.
Threaded feature options
| Option | Where it fits | RFQ risk to define |
|---|---|---|
| Plain tapped hole | Thicker sheet or light-duty thread engagement. | Thread depth, burr, tap breakage, and plating buildup. |
| Extruded and tapped hole | Thin sheet that needs more thread length. | Collar height, crack risk, form direction, and thread strength. |
| Thread forming | Materials that can displace cleanly without cutting chips. | Torque, material ductility, pilot size, and gage method. |
| Clinch nut or insert | Higher pull-out or repeat assembly needs. | Insertion force, sheet hardness, plating sequence, and push-out test. |
| Projection weld nut | Higher load or standard nut thread with welded hardware. | Weld position, torque, pull test, spatter, and coating sequence. |
Why extruded holes need early DFM review
An extruded hole is formed by pushing material around a pierced hole into a collar. The collar gives more thread engagement than sheet thickness alone. But the form can split if the material is too hard, the pilot hole is wrong, the flange height is too aggressive, or the feature is too close to an edge or bend.
The direction of extrusion matters. A collar that points toward an assembly surface may interfere with mating parts. A collar that points away may reduce accessible thread depth or change how the fastener starts. If the part will be plated after forming, the thread and collar must allow coating without creating fit problems. For finish planning, see the plating and passivation RFQ guide and plating thickness inspection guide.
Design checks before quoting
Start with sheet thickness and thread size. A large thread in thin material may need an insert or weld nut instead of an extruded hole. Also review hole-to-edge distance, distance to bends, material grain, hardness, and whether the collar will be formed before or after other operations.
For production, the quote should include how threads will be checked. Options include go/no-go thread gages, torque tests, push-out or pull-out tests for inserted hardware, and visual checks for cracks around the extrusion. If the threaded feature is a CTQ, connect it to the critical dimensions inspection plan, control plan checklist, and quality agreement checklist.
RFQ checklist for extruded holes and threads
- Thread size, thread class, fastener type, and mating part requirement.
- Sheet material, thickness, temper, hardness, and coating or plating route.
- Extrusion direction, collar height, and whether collar marks are allowed.
- Load direction, torque target, pull-out or push-out requirement if known.
- Distance to edge, bend, slot, embossed feature, or other formed area.
- Inspection method: thread gage, torque test, functional assembly, or fixture check.
- Annual volume, assembly environment, and whether thread chips are unacceptable.
When to choose hardware instead
If torque or pull-out strength is high, if the sheet is very thin, or if the thread will be used many times, a clinch nut or weld nut may be safer than formed threads. Hardware adds cost and process steps, but it can reduce field failures when the joint is loaded. The best route depends on drawing function, assembly method, qualification requirements, and acceptable secondary operations.
Zipụ the drawing, thread requirement, and assembly load through the kọntaktị page. If you have failed samples, stripped threads, or cracked extrusions, attach photos through the RFQ form so the quote can include the right process route and inspection evidence.
FAQ: extruded holes and thread forming
Why use an extruded hole instead of a plain tapped hole?
An extruded hole can provide more thread engagement in thin mpempe ígwè by forming a collar before tapping or thread forming.
Can every stamped material use thread forming?
No. Thread forming depends on material ductility, hardness, thickness, pilot hole size, coating, and the required thread strength.
When is a clinch nut better than an extruded thread?
A clinch nut may be better when higher thread strength, repeat assembly, or defined push-out and torque performance is required.
What inspection is needed for extruded threaded holes?
Inspection may include thread gage checks, collar height, crack inspection, torque tests, pull-out or push-out tests, and functional assembly checks.