Where this design fits

Heavy frames, brackets and captured-head fixture assemblies.

What to include in the RFQ

Show the wrench access or retaining pocket and required mechanical properties.

Material and acceptance

Carbon steel, 10B21, SUS304/316, aluminum, copper/brass and titanium alloy requirements can be discussed. Suitability is specific to the part, grade and process.

Define material condition, coating, critical dimensions and required inspection records. A named product family does not imply a tested load, pressure or performance rating.

RELEVANT PROCESS OPTIONS

Make the features work together.

These routes are options for technical review. The approved drawing, quantity and material determine the actual sequence.

Related product designs

Application discussions

Useful technical reading

Drawing and sample checks

Dimension head width, corner clearance and pocket depth
Verify seating and anti-rotation in the actual pocket.

Tool access or captured-head location

Decide whether the square is driven by a wrench or restrained in a pocket. The first needs tool clearance; the second needs pocket fit, insertion access and controlled anti-rotation contact. State the corner form and under-head transition so an apparently correct across-flat dimension does not hide an interference.

Review the route before fixing the quotation

For custom square head bolts, review Multi-Station Cold Heading, Hot Heading & Forging, Secondary & Precision Operations against the drawing and quantity. Identify which features can be produced in the initial shape and which require a separate setup. A change to a functional shoulder, bore, drive or thread can change the proposed route as well as the inspection effort.

The drawing review should resolve head size; captured fit; shank configuration. Keep material condition and finishing allowance attached to those requirements. Define the acceptance condition for critical features and approve any proposed dimensional change before comparing samples with the original assembly.

From drawing to approved samples

Show the wrench access or retaining pocket and required mechanical properties. Identify the drawing revision, prototype quantity and expected repeat demand. Where the first part is based on an existing sample, separately confirm material and hidden features rather than inferring them from appearance.

The typical sampling lead time, including tooling, is approximately 10–15 days. The schedule is confirmed after drawing review and agreement on the sample specification; material availability, special treatment and inspection requirements can affect the confirmed date. Confirm when the agreed schedule starts in the quotation. Sample approval and repeat-production delivery are separate milestones.

Custom Square Head Bolts