ZUFEK
Specify the two ends independently
Provide diameter, pitch, handedness, fit and usable length for each threaded end. Do not assume a repeated note applies to both ends if the interfaces differ. Show any thread runout or relief that affects seating against the center section.
Explain the center section
A plain shank, shoulder or wrench flat can serve a locating or assembly function. Dimension its axial relationship to both threads. Clarify whether a face should seat against a mating part or whether the stud is installed to a separate depth requirement.
Plan identification before packing
If the ends look similar, discuss permitted marks, packaging orientation or another agreed distinction. Avoid an unapproved color or permanent mark on a functional surface. Identification requirements should appear in the order documentation so repeat batches use the same method.
Gauge and review both interfaces
Each end needs the appropriate acceptance method for its own specification. Inspection records should identify the end being checked, especially when the same nominal diameter uses different pitches. A successful trial in one mating part does not establish the other end conforms.
Specification example
For a stud joining two different thread sizes, label the ends A and B on the drawing and use the same labels in the inspection plan. Keep that convention on sample reports and packaging instructions.
RFQ checklist
- Complete specification for both threads
- Center-section dimensions
- Installation sequence and seating
- Approved end identification
- Separate thread acceptance checks
Use the RFQ preparation checklist, then submit your drawing for review. For acceptance requirements, see quality planning.
General guidance only. Material properties, tolerances, standards and manufacturing feasibility must be verified for the actual specification. This article does not establish a product performance guarantee.