ASME B18.6.3 Square Recessed Pan Head Machine Screws

Documents

Shipments are backed by Mill Test Certificate (MTC), Dimensional Report, Salt Spray Test Report on request, with full batch traceability from raw material to finished product. Quality management follows the owner-confirmed compliance list: ISO 9001:2015, RoHS, REACH. Exact document sets are confirmed on the order.

Quotation

• The fastener family (ASME B18.6.3 Square Recessed Pan Head Machine Screws) plus the standard designation from your drawing — DIN / ISO / JIS / ASTM / ANSI, or a drawing for custom parts.
• Size (diameter and length), thread type (metric or inch), property class or grade, and coating or finish.
• Quantity per size and your target delivery date.
• Destination country, and any required documents (for example a mill test certificate) so the quote includes them.

Sample & supply

Minimum order quantity is 10,000 pieces. Stock items run 3–7 days. Quantities or variants outside the standard range are confirmed at quotation.

Storage & shipping

Parts are packed for export and shipped factory-direct to buyers in Europe, Asia, the Americas and the Middle East. Store fasteners dry and protected until installation, and keep coated parts in their packaging until use; specific packing and preservation requirements can be stated on the order and confirmed at quotation.

Square recess or Phillips — when does the drive choice matter?

Both recesses sit in comparable pan head envelopes — the collected table gives #10 as 0.373 in across by 0.137 in high, the same head the cross recessed pan head table carries — but they behave differently in the driver. The square recess locks the bit against cam-out through its tapered square walls, which suits one-handed driving, overhead work and torque-controlled stations; the Phillips is designed to cam out at high torque to protect the assembly. Choose by the tooling on the line and the installation position: where the driver must stay engaged without hand pressure, the square recess wins. State the drive explicitly on the RFQ — the two recesses are not interchangeable.

Why does the table quote sizes #4 through 5/16?

Every figure above is quoted verbatim from the collected ASME B18.6.3 cut sheet, which covers #4 through 5/16 with complete maximum and minimum columns. Larger machine screw sizes in the standard are available — the dimension figures for sizes outside the collected table are confirmed against the standard table at quotation rather than estimated here.

What is the MOQ and lead time for these square recess machine screws?

Minimum order quantity is 10,000 pieces per item. Stocked sizes ship in 3–7 days; non-stock sizes, lengths or finishes are quoted with a confirmed schedule. Common sizes in this designation are widely stocked — confirm the exact schedule against quantity and size mix at quotation.

What should an RFQ for these square recess machine screws state?

State the standard designation (ASME B18.6.3 — often still called ANSI B18.6.3) and drive type (square recessed; combination slotted + square recessed where both drives are wanted), nominal screw size and thread series with threads per inch, length and head style, material and grade (steel or stainless; state the stainless grade such as 18-8/A2 or 316/A4 if specified), finish (plain, zinc plated, or other), required certificates such as a mill test report per EN 10204 3.1, and quantity per size — plus destination country.