DIN 7982 Countersunk Tapping Screws (ISO 7050)
Cross recessed countersunk head tapping screws, Form C, per ISO 7050 — the current designation DIN 7982 C folds into — ST2.2 to ST6.3 in case-hardening steel per ISO 2702 or A2 stainless, thread per ISO 1478. The flush-finish self-tapping screw for countersunk sheet-metal joints.
Last updated: 2026-11
Specifications
The countersunk tapping screw disappears into the joint: a 90° conical head seated flush in a prepared countersink, driven by a cross recess, cutting its own thread per ISO 1478 as it goes. The collected ISO 7050 table runs ST2.2 through ST6.3 in case-hardening steel per ISO 2702 or A2 stainless. At ST4.2 the head seats at 8.1 mm maximum diameter with an approximate head height of 2.5 mm and a No. 2 cross recess (Type H depth ≈4.7 mm). The DIN 7982 designation survives as DIN 7982 C; the collected table names DIN 7982 C as the equivalent norm of ISO 7050. The countersink is part of the joint design — the flush finish this screw exists for depends on the mating seat being cut to match, so confirm the countersink spec together with the screw. Where no seat is prepared and clearance rather than flushness is the goal, the raised countersunk form (DIN 7983) covers the same thread range.
| Standard | ISO 7050 — cross recessed countersunk head tapping screws, Form C; DIN 7982 C is the equivalent national designation |
|---|---|
| Size range | ST2.2 – ST6.3 |
| Dimensions at ST4.2 | dk (head diameter) nominal=max 8.1 mm (min 7.74 mm); k (head height) approx 2.5 mm; cross recess No. 2; Type H m ≈4.7 mm; P 1.4 mm |
| Materials | Case-hardening steel per ISO 2702; stainless A2 |
| Thread | Tapping thread per ISO 1478 |
Materials
- Steel
- Stainless steel
Ordering & documentation
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 (DIN 7982 Countersunk Tapping Screws (ISO 7050)) 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.
Frequently asked questions
Does a countersunk tapping screw need a prepared countersink?
For the flush finish it is chosen for, yes. The 90° conical head of the ISO 7050 / DIN 7982 C form seats in a mating countersink; without one the head sits proud or, worse, digs an uneven seat into thin sheet and loses bearing. Sheet-metal punches and dimpling dies for the common ST sizes make this a fast operation in production. If the material is too thin to hold a full countersink, switch to the pan head form (ISO 7049 / DIN 7981 C), whose bearing face is designed to sit on the surface.
What is the MOQ and lead time for these screws?
Minimum order quantity is 10,000 pieces per item. Stocked sizes ship in 3–7 days; non-stock diameters, 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 screws state?
State the standard designation (for example DIN 914, DIN 915, DIN 7981/7982/7983 — or the ISO designation your drawing prints), thread or tapping size, length or head dimension, strength class or material (such as 45H, 4.8, A2-70, A4-80 or brass), finish (black oxide, zinc plated, or plain), required certificates such as a mill test report per EN 10204 3.1, and quantity per size — plus destination country.
Related knowledge
- Thread-Forming vs Thread-Cutting vs Thread-Rolling Self-Tapping Screws: What the Evidence Settles on Base Material
- Screw Family Selection by Base Material: Wood, Machine and Self-Tapping Threads, Engagement and Coating
- Hex Bolts vs Socket Head Cap Screws: What the Evidence Settles on Strength, Clearance and Cost
Request a Quote
Get factory-direct pricing from the manufacturer.
What to include in your inquiry
- ✓ Standard and property class (e.g. DIN 912, ISO 4762, class 8.8) — or a drawing for custom parts.
- ✓ Sizes, lengths and thread type (metric or inch).
- ✓ Quantity per size and your target delivery date.
- ✓ Destination country, plus any coating or finish requirement.
- ✓ Any documents you need with the shipment (e.g. mill test certificate) so the quote includes them.
- ✓ Your inquiry goes straight to the factory team by email and gets a reply within 24 hours.
- ✓ Factory-direct pricing
- ✓ Standard and custom specifications
- ✓ Factory-direct export to buyers in Europe, Asia, the Americas and the Middle East
- ✓ Full fastener family support