ASTM A194 GRADE 2HM NUTS
ASTM A194 Grade 2HM Nuts Sample MTC Certificate
Access a comprehensive, professionally formatted Material Test Certificate according to EN 10204-2004: 3.1 for Carbon Steel Heavy Hex Nuts modified for sour service (ASTM A194 Grade 2HM). Inspect the exact documentation your QA and engineering teams will receive with every Ananka Fasteners order.
What's Inside This A194 Gr 2HM MTC Certificate
This sample mill test certificate mirrors the rigorous QA documentation package standard for high-temperature carbon steel nuts, engineered and specially heat-treated to ensure safety in sour gas (H2S) environments.
- Full Traceability: Certified with TC No.: C195/26-XX and corresponding ASTM specifications.
- Material Chemistry: Detailed carbon steel breakdowns verifying optimal Carbon (0.40% min) and Manganese content, equivalent to standard Grade 2H, providing the structural foundation for heavy hex nuts.
- Strict Hardness Verification: Central to the 2HM specification, this document guarantees the maximum hardness does not exceed 235 HBW (22 HRC) to fully comply with NACE MR0175, mitigating the risk of Sulfide Stress Cracking (SSC).
- Mechanical & Proof Load Testing: Validates the nut's Proof Load capacity. To accommodate the necessary lower hardness limits, Grade 2HM has a reduced minimum proof load requirement (827 MPa / 120,000 psi) compared to standard Grade 2H.
- Heat Treatment Tracking: Verifies the necessary quenching and elevated-temperature tempering (minimum 1150°F / 620°C) required to soften the carbon steel to the precise NACE-compliant range.
Live Preview: ASTM A194 Grade 2HM Data
Review the standard parameters and layout before downloading the full document.
TC Number
C195/26-XX
TC Date
05.02.20XX
Material Spec
ASTM A194 GRADE 2HM
Nut Shape / Size
Heavy Hex Nut / M24
Dimensions / Item
Heavy Hex Nut M24-3.0P
Quantity
250.00 NOS
Chemical Composition %
| C | Mn | P | S | Si |
|---|---|---|---|---|
| 0.44 | 0.78 | 0.021 | 0.012 | 0.25 |
| Min: 0.40 | Max: 1.00 | Max: 0.040 | Max: 0.050 | Max: 0.40 |
Mechanical Properties
| PROOF LOAD STRESS (MPa) | HARDNESS (HBW) |
|---|---|
| 845.50 | 210, 215, 212 |
| Min: 827 (120 ksi) | Min: 159 Max: 235 (22 HRC max) |
Standard References & Compliance
Our MTC certificates map to the demanding industrial standards for pipeline and structural fasteners in sour environments. The test reports confirm compliance with As Per ASME/ASTM A194 Grade 2HM with respect to the tests carried out, specifically ensuring strict hardness controls.
| Standard / Requirement | Confirmation on Certificate |
|---|---|
| Visual Inspection | 100% visual inspection carried out & found free from defects. |
| Sour Service Compliance | Hardness verified max 22 HRC (235 HBW) complying with NACE MR0175 / ISO 15156. |
| Safety Requirements | Material is free from radioactive contamination. |
| Dimensional Accuracy | All dimensions, threads, and bearing surface tolerances conform to ASME B18.2.2. |
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
- NACE MR0175 Conformity guaranteed
- Certified ISO 9001: 2015 Company
Heat Treatments
- Quenched & Tempered
- Tempering Temperature: Min 1150°F (620°C)
Testing Conditions
- 100% Hardness testing performed per ASTM A194 rules for 2HM
- 100% visual inspection carried out
Technical FAQs — ASTM A194 Grade 2HM MTC Certificate
What is the difference between Grade 2H and Grade 2HM?
Both grades share the exact same raw material chemistry (Carbon steel, 0.40% min C). However, Grade 2HM is "Modified" ("M") for sour service. To achieve this, Grade 2HM is tempered at a much higher temperature to soften the material, strictly limiting its maximum hardness to 235 HBW (22 HRC). Because it is softer, Grade 2HM has a correspondingly lower minimum proof load than standard Grade 2H.
Why is the hardness strictly limited for Grade 2HM?
The "M" designation ensures the nut is safe for use in environments containing Hydrogen Sulfide (H2S), typical in petrochemical refineries and wellhead operations. High hardness in carbon steel dramatically increases its susceptibility to Sulfide Stress Cracking (SSC). Keeping the hardness at or below 22 HRC complies with NACE MR0175, preventing catastrophic brittle failures.
Why is 100% hardness testing explicitly mentioned?
Because the hardness limit is a critical, life-saving factor in preventing sour gas cracking, ASTM A194 strictly requires that 100% of Grade 2HM nuts (and other 'M' grades) be individually tested for hardness. This ensures that no single nut in an entire production batch exceeds the 235 HBW / 22 HRC safety threshold.