Tensile Strength, Yield Stress, Residual Stress, Fracture Toughness | NDT Mechanical Properties Analysis
LPR Global’s AIS series of non-destructive testing equipment is used to inspect mechanical properties of materials and structures operating under high-pressure, high-stress, high-temperature and other harsh environments. It is essential for power plant and pipeline operators and service providers to closely monitor structural deformation and degradation of materials caused by mechanical, chemical and thermal effects in order to adhere to regulatory requirements and to prevent industrial accidents.
LPR Global offers NDT equipment which uses Instrumented Indentation Technology (depth indentation). This NDT equipment is ideal for API pipe inspections and inspections related to PHMSA tensile and yield strength properties testing.
Instrumented Indentation Test Theory & Procedure
Non-Destructive IIT Method vs. Destructive Tensile Tests
AIS series equipment uses the load-depth indentation method to build a stress-strain curve, and to obtain tensile strength and yield stress data.
When compared to destructive test results, our NDT equipment’s in-field accuracy shows less than 10% deviation.
Instrumented Indentation NDT for Aged Material Degradation Monitoring
Instrumented indentation technology overcomes the limitations of conventional non-destructive testing techniques in measuring mechanical property degradation of long-term aged materials by analyzing the indentation load-depth curves that reflects the deformation behavior of the tested sample, which is non-destructively assessed by the indenter on a micro scale.
Instrumented Microindentation Study on Long-term Aged Materials
Power Plant Equipment and Structure NDT Inspection
The AIS series of NDT equipment offered by LPR Global has been used to inspect power plant and nuclear power plant facilities. Due to the advanced attachment options compatible with the AIS NDT equipment, we have performed inspection and non-destructive testing of a variety of power plant equipment and structures, including turbine rotor, turbine casing, shafts, boiler tube, weldment, weld overlay, reactor, cooling water line, steam generator and heater tube.
NDT Equipment for Nuclear and Power Plant Applications
High-Speed Railway (Wheel and Rail) Defects NDT Inspection
Common types of damages to high-speed rail such as crack propagation, surface peeling/spalling, work hardening/ shelling, abrasion and other surface and subsurface defects can occur due to repeated wheel load and other impacts. If left unchecked, these railway damages and deteriorations can be detrimental to the safe operation of the railway and the safety of railway passengers and operators.
AIS NDT equipment offered by LPR Global can be used to perform systematic and periodic non-destructive inspections to detect rail and wheel defects of in-service railways. In addition, AIS equipment can be used to inspect new materials and railway components, eliminating the introduction of defective parts to ensure the quality and safety of new systems and replacement parts.
Non-Destructive Material Verification for PHMSA Mega Rule
LPR Global’s AIS NDT equipment is used for PHMSA regulatory inspection of tensile strength and yield stress for material verification of unknown pipes.
PHMSA (Pipeline and Hazardous Materials Safety Administration) regulation by the U.S. government Department of Transportation (DOT) requires all pipelines constructed before 1970 to have confirmation of the MAOP (maximum allowable operating pressure) as defined by TVC (Traceable, Verifiable and Complete) records of material tensile strength and yield stress. To ensure regulatory compliance, pipeline owners are required to update incomplete and inaccurate pipeline information to ensure accurate risk assessment and effective risk management. To achieve regulatory compliance, PHMSA requires companies to perform yield and tensile strength inspections using non-destructive technologies (NDT).
The requirements for testing technologies are specified in the §192.607 section of the Mega Rule.
***PHMSA 192.607: Must achieve at least 95% confidence level***
- 3rd party application cases proves that IIT used by AIS equipment offered by LPR Global meets this confidence requirement
- Ultimate Yield Strength (UYS) +/-10% with a 95% confidence level
- Ultimate Tensile Strength (UTS) +/-10% with a 95% confidence level
Recent report by the Gas Technology Institute (GTI) tested and verified the accuracy and effectiveness of the instrumented indentation technology (IIT) used by the AIS series of NDT equipment. In this research, GTI’s optimum causal models combined with the AIS technology data achieved a 95% confidence level in ultimate tensile strength and yield strength predictions by overlapping yield and ultimate tensile strength from lab tests across the entire pipe sample DOE on non-seamless pipes, including pipes with long seam welds like ERW and SAW.
AIS series NDT equipment is recognized as an accurate, reliable, efficient, and cost-effective tool for material property confirmations of service pipelines to meet the new U.S. government Department of Transportation (DOT) PHMSA regulations.
AIS Non-Destructive Testing (NDT) and Inspection Equipment Benefits
Tensile Strength, Yield Stress NDT Inspection | AIS2100 NDT
Testing for tensile properties such as tensile strength and yield stress can be done accurately and non-destructively with the AIS2100 unit. This non-destructive NDT inspection and testing equipment is portable for in-field operations to obtain precise load and depth data with real time data generation and reporting.
In-field AIS2100 model generates an indentation load depth curve used to show tensile properties such as flow curve, yield strength, tensile strength, and work hardening exponent.
The AIS2100 unit is equipped with a high power motor and high-strength decelerator to precisely control equipment positioning. AIS2100 is equipped with multiple indenters for Rockwell A/C/D and Vickers hardness measurement.
LPR Global provides complete non-destructive testing (NDT) machine package with mounting hardware and attachment jigs for complex test sites. Attachment options designed for complex structures include mechanical chain, U-block, V-block, flat magnets and curved magnets. We are capable of designing customized specialty attachment jigs according to specific client request. All indentation components and custom software for analysis and reporting are provided.
Tensile Strength | Yield Stress
Tensile strength and yield stress AIS2100 NDT Inspection Machines in action in laboratories and in-field sites, equipped with suitable attachment jigs:
Tensile Stress and Yield strength AIS2100 Nondestructive (NDT) Testing Equipment Specification
Size | 180 x 180 x 430 mm (14 kg) | ||
Maximum Load | 300 kgf | ||
Resolutions (Load / Depth) | 100 gf / 0.2um | ||
Full Stroke | 40 mm | ||
Loading rate | 0.05 - 30 mm / min | ||
Communication | RS-422 | ||
Data acquisition rate | 30 / sec | ||
Adapter | AC 110 V - 220 V | AC 110 - 220 V (free voltage) | |
Battery | Portable battery (Lasts for 10 hrs) | ||
Standard | Lap-top PC (w / SW) | Lap-top PC (w / SW) | |
Special | Rugged Computer (Optional) | ||
WC spherical indenter (Dia. 0.5 / 1.0 mm) Vickers, Rockwell C indenter | WC spherical Indenter (Dia. 0.5 / 1.0 mm) Vickers Indenter | ||
(Select or option) | Field | Multicurve magnet Flat magnet Light-weight mechanical chain U / V-block (- 6 inch) | |
Laboratory | Precise X-Y axis stage Various vises (plate / clamping jig) | Precise X-Y axis stage Various vises (plate /c lamping jig) |
Residual Stress, Tensile Strength | AIS2100
AIS2100 | Yes | N/A | Extra payment Required for this Option | Extra payment Required for this Option |
AIS2100 Nondestructive Testing & Inspection Machine | Instrumented Indentation Technique ITT
In-field Testing Procedure Software | AIS Nondestructive Testing and Inspection Equipment
Residual Stress, Fracture Toughness Measurement | AIS3000 | NDT
The AIS3000 nondestructive testing equipment uses the Instrumented Indentation Technique to obtain data for residual stress, yield strength, tensile strength, and elastic modulus.
The AIS3000 nondestructive testing and inspection machine can evaluate residual stress from welds or structures and equipment. With an indentation of less than 150µm, the AIS3000 provides non-destructive, accurate, and repeatable results.
With its portability, ease of use, and wireless communication capabilities, the AIS3000 performs nondestructive, on-site evaluation efficiently and accurately.
Advantages of using the AIS3000 include:
The AIS3000 nondestructive NDT testing and inspection machine package includes:
The AIS3000 portable nondestructive testing and inspection machine in action in laboratories and field sites:
Tensile Properties, Residual Stress, Fracture Toughness | AIS3000 Equipment Specification
Size | 5.6 gf / 0.1um | ||
Maximum Load | 300 kgf | ||
Resolutions (Load / Depth) | 5.6 gf / 0.1um | ||
Full Stroke | 40 mm | ||
Loading rate | 0.05 - 60 mm / min | ||
Communication | RS-422/ wireless module | ||
Data acquisition rate | 100 / sec | ||
Adapter | AC 110 V - 220 V | AC 110 - 220 V (free voltage) | |
Battery | Portable battery (Lasts for 10 hrs) | ||
Standard | Lap-top PC (w / SW) | Lap-top PC (w / SW) | |
Special | Rugged Computer (Optional) | ||
WC spherical indenter (Dia. 0.5 / 1.0 mm) Vickers, Rockwell C indenter | WC spherical Indenter (Dia. 0.5 / 1.0 mm) Vickers Indenter | ||
(Select or option) | Field | Multicurve magnet Flat magnet Light-weight mechanical chain U-block (3 - 6inch) Multi-point dovetail slider | |
Laboratory | Precise X-Y axis stage Various vises (plate / clamping jig) | Precise X-Y axis stage Various vises (plate /c lamping jig) |
AIS3000 Residual Stress, Tensile Strength
AIS3000 | Yes | Yes | Extra payment Required for this Option | Extra payment Required for this Option |
Tensile Properties, Residual Stress | AIS Series | Material Verification for API Pipes
/ Microindentation / Macroindentation (Micro AIS / AIS 2100 or AIS3000) | ||
---|---|---|
Instrumented - instrumented does not equal automated continuous depth-sensing (10) | Everything's controlled using computer, continuous indentation test. User selects the method of load control and displacement control then tests with it. continuous indentation test invented back in 1977 (7) | |
Ultra-low load, nano-indentation (0.05 N≤ F ≤0.50 N) (4) (5) | Micro-indentation: 0.1 mN ≤ F ≤ 20 N Macro-indentaiton: 10 mN ≤ F ≤ 3000 N | |
Nano range: h ≤ 0.2 μm (4) (5) | Micro-indentation: 0.01 μm ≤ h ≤ 15 μm Macro-indentaiton: 0.1 μm ≤ h ≤ 40000 μm | |
Pyramidal Berkovich, (4) (5) Small ball indenter (<50μm) rarely used due to unacceptable geometry | Spherical (Not weld & not housing, The gap doesn't exist between indenter and body) Microindentation: ≥25μm Macroindentation: ≥250.μm Micro Vickers / Vickers | |
Curve | Linear | |
No | Yes | |
Analytical and optical | Analytical | |
No calibration blocks exist for Martens hardness or indentation modulus | Load cell calibrated per ASTM E4 and E74 Depth sensor calibration: Cycle is every 250 years (Optical type) | |
Yes | No | |
Yes | N/A | |
No | Yes (No need of reference) Nondestructive (6) (8) | |
No | Yes (No need of reference) Nondestructive (6) (8) | |
No | Yes (No need of reference) Nondestructive (6) (8) | |
No | Yes (No need of reference) Nondestructive (6) (8) | |
Limited 1-lab, 1-machine (nano range), Berkovich indenter. No demonstrated inter-laboratory precision values. Machine was not verified and no calibration blocks used. | Yes, complete 6-lab ILS per ASTM E691, ILS report submitted to ASTM E28 | |
No | Yes (9) | |
Indentation Modulus (3) * Indentation Modulus may or may not correlate to elastic modulus | Yes (No need of reference) (3) Nondestructive | |
Yes - Martens Hardness from quasi-destructive pyramidal Berkovich indenter. Martens hardness cannot be obtained from spherical indenter (3) | Vickers hardness using Instrumented Indentation Technique - IIT (3) | |
Yes | Yes (Micro indentation) | |
Yes | N/A | |
Yes | N/A |