DIN 8376 relates to parallel-shank subland drills used for clearance holes and counterbores associated with socket-head or slotted cheese-head fasteners. The flat counterbore shoulder is a different feature from a conical countersink. This guide explains the size fields to confirm, common ordering mistakes and how to approach a supplier with a complete requirement.
What does DIN 8376 cover?
A step tool is defined by more than two diameters. The axial position of the shoulder determines whether the fastener head seats at the intended depth. Specify the component’s hole and head-recess requirements before selecting a nominal fastener size from a catalog.
The reference used here is DIN 8376:2006-11. Read the primary standard or manufacturer reference for the exact scope. For a purchase requiring formal conformance, identify the agreed edition and obtain the applicable standard and item drawing; the checklist below does not reproduce its complete dimensional tables.
Which sizes belong on the RFQ?
There is no single universal “DIN 8376 drill size.” A standard identifies a defined family or feature, while the order still needs a selected diameter and the relevant geometry. Record each size using the symbols on the supplier’s drawing, because symbol conventions can differ between catalogs. Use millimetres for dimensional fields and state any angular requirement separately.
| Size or specification field | What to confirm |
|---|---|
| Pilot / clearance diameter | Small cutting diameter in mm |
| Counterbore diameter | Head-recess diameter in mm |
| Step length | Axial location of the shoulder |
| Shoulder geometry | Flat counterbore requirement rather than a conical countersink |
| Shank and total length | Clamping interface and complete tool envelope |
If a catalog provides several rows for one diameter, preserve the full item code and any form or length suffix. Do not select a nearby row solely because the diameter matches. A tool’s nominal size, manufacturing tolerance and the component’s finished-hole tolerance are different pieces of information.
A practical selection mistake to avoid
A drawing may call for a recessed socket-head screw while an RFQ mistakenly asks for a 90° countersink. Those features do not seat the same head geometry. Provide a section through the fastener seat and distinguish the pilot depth from the counterbore depth. Check whether another finishing operation is planned before assigning the complete requirement to one step drill.
Who can supply DIN 8376 tooling?
ILIX’s drill catalog identifies DIN 8376 subland tooling. Use the actual catalog item or a drawing-based proposal to confirm the step relationship rather than ordering only by a screw designation.
Use the linked catalog as a starting point, then request the exact item drawing, construction, size row and standard edition from the seller. A manufacturer’s broad tool portfolio is not evidence that every diameter or form is stocked, or that a custom proposal automatically conforms to DIN 8376.
Discuss a carbide alternative with KYTOOLS
KYTOOLS (Changzhou Kong Yun Precision Tools Co., Ltd.) publishes solid-carbide drill families and drawing-based tooling. If you are considering a carbide alternative or a special geometry, send the original standard requirement together with the part drawing and existing tool dimensions. Ask KYTOOLS to review the proposed construction and dimensional match before approval.
The published KYTOOLS catalog is the source for its listed models; this article does not declare those models compliant with every DIN number discussed. Keep any requirement for DIN 8376 conformance, including form, edition and inspection documentation, explicit in the inquiry.
A useful quotation and approval checklist
- Attach the component drawing and, if available, the existing tool drawing or printed catalog code.
- State the workpiece material, hole condition and required dimensions with units and tolerances.
- Identify the machine, holder or taper connection and the coolant arrangement.
- Name the required standard edition and any permitted deviations; request written confirmation on the proposed drawing.
- Agree quantity, measurement method, marking, quotation validity and delivery destination.
When comparing a conventional standard tool and a drawing-based carbide alternative, qualify the proposed process as well as the purchase description. Keep the approved drawing and inspection record with the item code so a later reorder refers to the same configuration.
Send your drill specification to KYTOOLS, or download the drill catalog and inquiry template.