ZUFEK
Record the limiting section and the inspection access
Worked review only. Inputs and acceptance criteria belong to the actual drawing; no customer test result or universal performance rating is claimed.
- Section result
- 1.30 mm is the calculated remaining wall for the stated teaching inputs, not a safe-wall recommendation or pressure rating.
- Separate internal-edge decision
- Identify the intersecting hole and burr requirement, the deburring stage and a suitable check before later assembly limits access.
Describe the entire passage
Identify whether the hole is through, blind, stepped or connected to a side passage. Dimension each section and its axial position. A single opening diameter does not define an internal path, and a photograph cannot establish hidden counterbores or restrictions.
Review wall thickness with the thread
The bore and external thread share the same material section. Show their relationship through the thinnest region and identify any concentricity or position requirement. Manufacturing review needs the actual geometry; an outside diameter alone is not sufficient to evaluate a hollow threaded feature.
State edge and cleanliness requirements
Drilling can leave burrs at hole exits and intersections. Specify which edges must be broken and how internal burrs will be accepted. If the part carries fluid, adhesive or a wire, explain the relevant contamination, surface-damage or blockage concern rather than relying on a generic clean note.
Define functional tests separately
A continuous bore does not itself prove pressure capability, leak tightness or unrestricted flow in an assembly. State any test medium, fixture arrangement and acceptance method that the application requires. These conditions should be agreed before sampling so manufacturing and inspection can be quoted together.
Worked review: include bore offset in the wall calculation
For an illustrative circular section, take a lower-limit thread-root envelope diameter of 6.00 mm, an upper-limit bore diameter of 3.00 mm and a maximum radial bore-centre offset of 0.20 mm. The minimum remaining wall in that section is (6.00 − 3.00) ÷ 2 − 0.20 = 1.30 mm. The offset is a radial distance here, not a diametral position-tolerance callout. This calculation does not cover cross-hole intersections, other local sections or load capacity. Derive the actual inputs from the controlled geometry and its tolerance limits.
Specification example
For a screw used as a cable passage, show the cable envelope and the edges it contacts. For a fluid passage, describe the intended sealing interface separately from the through hole.
RFQ checklist
- Complete bore section
- Minimum wall and feature relationship
- Hole exit and intersection burr limits
- Internal cleanliness requirements
- Required functional test method
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.