Description
Overview
DIN 916 defines a hexagon socket set screw, commonly called a cup point grub screw. The headless design allows the screw to sit inside or flush with the component, while the cup point bites into the mating shaft or surface to resist movement.
This selected size is specified with diameter M20, length 50 mm, thread M20, pitch 2.5 mm.
Sold in multiples of '10 pieces. 1 Box = '10 pieces.
Material, Grade & Strength
Grade 12.9 is a very high strength alloy steel property class with a nominal ultimate tensile strength of about 1200 MPa and yield strength of about 1080 MPa. It is used where maximum clamp load is needed and should be installed with correctly rated mating components and controlled tightening practice.
Finish & Corrosion Protection
Plain finish fasteners have no protective plated coating and are best used indoors, in oiled assemblies, in painted structures or where corrosion exposure is controlled.
Typical Uses
DIN 916 cup point grub screws are used for collars, pulleys, gears, handles, knobs, hubs, shaft-mounted components and mechanical adjustments where a protruding head is not required.
Technical Tips
- The cup point can mark the shaft or mating surface, which is useful for grip but may not suit delicate components.
- Use the correct hex key size to prevent rounding the socket.
- Apply threadlocker where vibration is present.
- For repeated adjustments, consider whether the point style is suitable for the shaft material.
Frequently Asked Questions
What does the cup point do? The cup point digs slightly into the mating surface to improve grip and resist rotation or sliding.
Dimensions – DIN 916 / ISO 4029 M20 x 50
| Standard | DIN 916 / ISO 4029 |
|---|---|
| Product | Hexagon socket set (grub) screw, cup point |
| Thread | M20 x 2.5 |
| Length (l) | 50 mm |
| Hex key (s) | 10 mm |
| Point | cup point |
| Weight (calculated) | 98.89 kg per 1 000 pieces |
Material, Grade & Strength
| Material | High tensile alloy steel, property class 12.9 |
|---|---|
| Property class | 12.9 |
| Tensile strength Rm (min) | 1220 MPa |
| Yield / 0.2% proof Rp0.2 (min) | 1100 MPa |
| Proof load stress | 970 MPa |
| Hardness | 385-435 HV |
| Elongation after fracture (min) | 8 % |
| Matching nut | property class 12 (ISO 898-2) |
Finish & Corrosion Protection
Plain / self colour: No applied coating. Stainless, brass and nylon parts are supplied plain; plain steel parts need oil, paint or protected environments.
DIN 916 data sheet – all sizes
| Size | Thread | Hex key (s) | Point |
|---|---|---|---|
| M3 | M3 x 0.5 | 1.5 mm | cup point |
| M4 | M4 x 0.7 | 2 mm | cup point |
| M5 | M5 x 0.8 | 2.5 mm | cup point |
| M6 | M6 x 1 | 3 mm | cup point |
| M8 | M8 x 1.25 | 4 mm | cup point |
| M10 | M10 x 1.5 | 5 mm | cup point |
| M12 | M12 x 1.75 | 6 mm | cup point |
| M16 | M16 x 2 | 8 mm | cup point |
| M20 | M20 x 2.5 | 10 mm | cup point |
| M24 | M24 x 3 | 12 mm | cup point |
Nominal dimensions per DIN 916 / ISO 4029. Weights are calculated from nominal dimensions and are a guide only (±10%). Values for fit and strength should be confirmed against the standard for critical applications.
Specifications
| Measurement Type | Metric |
|---|---|
| Thread Size | M20 |
| Thread Pitch | 2.5 mm |
| Thread Style | Fully Thread |
| Drive Size | 10 mm |
| Drive Type | Hex |
| Point Type | Cup Point |
| Diameter | M20 |
| Length | 50 mm |
| Material | Hi - Tensile Steel |
| Finish | Plain |
| Grade | Grade 12.9 |
| Standards Met | ISO 4029, DIN 916 |
| Package Quantity | 10 |
| Package Type | Box |