Standards
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175 / ISO 15156-2
- NORSOK M-650 Qualified
- API 6A Certified
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
Incoloy 925 Socket Head Cap Screws (UNS N09925)
Internal-hex-drive cylindrical-head cap screws ASME B18.3 / DIN 912 / ISO 4762
Incoloy 925 socket head cap screws (SHCS), also called Allen-head cap screws or Inbus screws, are precision cylindrical-head fasteners with an internal hex drive recess. The internal hex drive (vs the external hex of a hex cap screw) means the wrench fits inside the head profile rather than around it, allowing the screw to be installed in counterbored holes, in tight clearance against adjacent surfaces, or where an external-hex wrench cannot reach. The cylindrical head shape gives a compact form for tight-clearance applications. SHCS are the standard fastener for machine-tool assembly, instrument enclosure mounting, hydraulic manifold ports, and any precision joint requiring high-strength fastening with a clean / low-profile head appearance. TorqBolt manufactures Incoloy 925 SHCS in M3 to M30 (#4 to 1-1/4") sizes ASME B18.3 (inch) / DIN 912 / ISO 4762 (metric), in the solution-annealed and aged condition with hardness controlled within the 35 HRC NACE MR0175 sour-service cap.
Need Incoloy 925 SHCS? Email info@torqbolt.com with diameter × length, thread series, head style (standard / low-head / button head / shoulder), quantity. WhatsApp +91-22-66157017.
SHCS Variants Manufactured
| Variant | Description | Standard |
|---|---|---|
| Standard SHCS | Tall cylindrical head + hex socket | ASME B18.3 / DIN 912 / ISO 4762 |
| Low-head SHCS (LHSHCS) | Short head height for tight-clearance applications | ASME B18.3 low-head / DIN 7984 |
| Button-head SHCS | Domed head + smaller hex socket | ASME B18.3 button / DIN 7380 / ISO 7380 |
| Flat-head socket cap screw | 82° countersunk head + hex socket; flush installation | ASME B18.3 / DIN 7991 / ISO 10642 |
| Shoulder bolt (stripper bolt) | Precision unthreaded shoulder + threaded tip + SHCS head | ASME B18.3 shoulder / DIN 9841 / ISO 7379 |
Standard Size Range
| Diameter | UNC (inch) | Metric Coarse | Hex Socket Size | Length Range |
|---|---|---|---|---|
| #4 / M3 | UNC 40 | M3 × 0.5 | 3/32" / 2.5 mm | 5 to 50 mm |
| 1/4" / M6 | UNC 20 | M6 × 1.0 | 3/16" / 5 mm | 10 to 100 mm |
| 5/16" / M8 | UNC 18 | M8 × 1.25 | 1/4" / 6 mm | 12 to 120 mm |
| 3/8" / M10 | UNC 16 | M10 × 1.5 | 5/16" / 8 mm | 15 to 150 mm |
| 1/2" / M12 | UNC 13 | M12 × 1.75 | 3/8" / 10 mm | 20 to 200 mm |
| 5/8" / M16 | UNC 11 | M16 × 2.0 | 1/2" / 14 mm | 25 to 250 mm |
| 3/4" / M20 | UNC 10 | M20 × 2.5 | 5/8" / 17 mm | 30 to 300 mm |
| 1" / M24 | UNC 8 | M24 × 3.0 | 3/4" / 19 mm | 40 to 350 mm |
| 1-1/4" / M30 | UNC 7 | M30 × 3.5 | 7/8" / 22 mm | 50 to 400 mm |
Mechanical Properties (Aged)
Tensile 165 ksi min / Yield 110 ksi min / Elongation 18% min / Hardness 32–35 HRC (NACE cap) / Charpy at -46°C: 40 J min. See full mechanical properties page.
Applications
- Machine-tool assembly (sour-service production machinery)
- Hydraulic / pneumatic manifold port plugs + cap screws
- Instrument enclosure mounting (subsea + topside)
- Counterbored / flush-surface joints (low-head SHCS or flat-head SCS)
- Sliding-component shoulder bolts (precision shoulder bolt variant)
- Marine equipment internal fastening (where external-hex wrench cannot reach)
- Choke valve trim assembly (sour-service chokes per SSV page)
Standards
- ASTM B805, UNS N09925 forging stock
- ASME B18.3, Socket Cap, Shoulder, Set Screws (inch)
- DIN 912 / ISO 4762, Hexagon Socket Head Cap Screws (metric)
- DIN 7984, Low-Head SHCS
- DIN 7380 / ISO 7380, Button-Head SHCS
- DIN 7991 / ISO 10642, Flat-Head Socket Screw (countersunk)
- DIN 9841 / ISO 7379, Shoulder bolt
- ASME B1.1 / B1.13M, thread series; NACE MR0175 Table A.10; API 6A; EN 10204 3.1 / 3.2
Manufacturing Sequence
- Bar input per ASTM B805 in annealed condition
- Cold-upset cylindrical head with integral hex socket (header press with hex-broach die)
- Shank machining + thread rolling (annealed condition)
- Solution anneal + age cycle per heat-treatment specification
- Final inspection: hex socket Go / No-Go, head dimensions, thread Go / No-Go, 100% hardness, sample tensile
- Marking: heat number on head face + grade designation + NACE stamp (sour orders)
Frequently Asked Questions
What's the difference between SHCS and a hex cap screw? SHCS uses an INTERNAL hex drive (Allen wrench inside the head); hex cap screws use an EXTERNAL hex drive (wrench around the head). SHCS is preferred where the head sits in a counterbore or against an adjacent surface that blocks an external wrench.
What's a shoulder bolt? A shoulder bolt has a precision-ground unthreaded shank (the "shoulder") between the SHCS head and the threaded tip. The shoulder acts as a precision pivot or sliding bearing surface, common in stripper plates, jigs, fixtures, and rotating linkages.
Lead time? Standard sizes M5 to M16: 4–6 weeks. Larger / specialty (low-head, button-head, flat-head, shoulder bolt): 6–8 weeks.
Documentation Package & Related Products
EN 10204 3.1 MTC (3.2 with TPI on request); chemistry, tensile, 100% hardness, hex socket gauge, thread Go/No-Go, NACE MR0175 reference. Related: hex cap screws, hex bolts, washers, set screws, full datasheet.
Request a Quote
Email info@torqbolt.com · Phone +91-22-66157017 · WhatsApp +91-22-66157017. Specify variant, diameter × length, thread series, quantity, applicable standards (ASME B18.3 / DIN 912 / ISO 4762), MTC level, coating.
References: ASTM B805; ASME B18.3; DIN 912 / 7984 / 7380 / 7991 / 9841; ISO 4762 / 7380 / 10642 / 7379; ASME B1.1 / B1.13M; NACE MR0175 / ISO 15156-3 Table A.10; EN 10204. INCOLOY® is a registered trademark of Special Metals Corporation.
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