ASTM A194 GRADE 4
ASTM A194 Grade 4 Nuts Sample MTC Certificate
Access a comprehensive, professionally formatted Material Test Certificate according to EN 10204-2004: 3.1 for High-Strength Carbon-Molybdenum Fasteners (ASTM A194 Grade 4). Verify chemical layouts, strict mechanical testing, and heat treatment certifications carried out for elevated temperature and high-pressure system operations.
What's Inside This A194 Grade 4 MTC Certificate
This sample mill test certificate mirrors the rigorous QA documentation package standard for highly durable Carbon-Molybdenum alloy heavy hex nuts shipped for critical services globally.
- Full Traceability: Certified with TC No.: S62/26-XX and corresponding standard structural heat lot tracking criteria.
- Carbon-Molybdenum Chemistry: Detailed analysis showing the accurate integration of Carbon (0.40-0.50%) and Molybdenum (0.15-0.25%), optimizing long-term creep resistance and localized thermal strength.
- Strict Impurity Limits: Documented check data verifying strict minimum boundaries on Phosphorus (0.040% max) and Sulfur (0.040% max) variables to limit internal hydrogen or thermal fracturing.
- Mechanical & Hardness Limits: Comprehensive breakdown including Brinell hardness testing properties ranging between 248 to 352 HBW to preserve threads under extreme preload conditions.
- Quality Compliance: 100% visual inspection carried out and verified free from defects and radioactive contamination.
Live Preview: ASTM A194 Grade 4 MTC Data
Review the standard parameters and layout before downloading the full document.
TC Number
S62/26-XX
TC Date
12.05.20XX
Material Spec
ASTM A194 Grade 4 - 2024
Nut Profile / Size
Heavy Hex Nut / M20
Dimensions / Item
Heavy Hex Nut M20 x 2.5P
Quantity
850.00 NOS
Chemical Composition %
| C | Mn | P | S | Si | Mo | Fe |
|---|---|---|---|---|---|---|
| 0.45 | 0.78 | 0.018 | 0.012 | 0.24 | 0.21 | Rem |
| Min: 0.40 Max: 0.50 |
Min: 0.60 Max: 0.90 |
Max: 0.040 | Max: 0.040 | Min: 0.15 Max: 0.35 |
Min: 0.15 Max: 0.25 |
Rem |
Mechanical & Hardness Properties
| BRINELL HARDNESS (HBW) | ROCKWELL HARDNESS (HRC) | PROOF LOAD STRESS (MPa) |
|---|---|---|
| 285 | 30 | 1035 |
| Min: 248 Max: 352 |
Min: 24 Max: 38 |
Min: 1030 (Heavy Hex) |
Standard References & Compliance
Our material tracking packages coordinate perfectly with the safety protocols expected by oil, gas, and energy development operators. Visual and surface inspections meet requirements with 0% defects observed.
| Standard / Requirement | Confirmation on Certificate |
|---|---|
| Visual Inspection | 100% visual inspection carried out & found free from defects. |
| Safety Requirements | Material is certified free from radioactive contamination. |
| Weld Repairs | No weld repairs performed on finished elements. |
| Dimensional Accuracy | All dimensions verified strictly as per standard ASME B18.2.2 guidelines. |
Certification Details
We confirm that above mentioned Items was Manufactured, Sampled, Tested and Inspected in accordance with the subjected Customer's Purchase Order and as applicable Drawings, Material Specifications, Codes & Standards and the results of the items have been determined to meet the users' requirements.
Documentation Standard
- EN 10204-2004: 3.1 Standard
- Free from radioactive contamination
- Certified ISO 9001: 2015 Company
Heat Treatments
- Liquid Quenched (Oil or Water)
- Reheated to a tempering minimum of 565°C (1050°F)
Testing Conditions
- Thread proof load and structural hardness tracked at 25°C
- 100% thread gauge checking carried out
Technical FAQs — ASTM A194 Grade 4 MTC Certificate
Why is the Molybdenum element critical for Grade 4 nuts?
Molybdenum increases the high-temperature structural capacity of the nut by preventing creep deformation under heavy loads. It also mitigates temper embrittlement risks during the specialized heat treatment process, ensuring long-term microstructural reliability up to service levels around 538°C (1000°F).
How does Grade 4 differ from Grade 7 nuts under ASTM A194?
While both contain Molybdenum for elevated temperature use, Grade 4 uses a higher nominal Carbon range (0.40-0.50%) without deliberate Chromium additions, relying on simple carbon-moly compounding for high strength. Grade 7 is a full AISI 4140 type Chromium-Molybdenum alloy steel, which provides higher absolute hardenability and tougher core dynamics across very large nut profiles.
What are the maximum hardness criteria outlined in standard MTC data sheets?
Under ASTM A194, Grade 4 heavy hex nuts must strictly fall within a Brinell hardness limit of 248 to 352 HBW (or Rockwell 24 to 38 HRC). Exceeding these limits increases brittle fracture risks, while falling below them impairs thread strip and proof load ratings.