Crack Growth Behavior of Sealing Rubber under Static Strain in High-Pressure Hydrogen Gas

Abstract Following the ASME codes, the design of pipelines and pressure vessels for transportation or storage of high-pressure hydrogen gas requires measurements of fatigue crack growth rates at design pressure. However, performing tests in high pressure hydrogen gas can be very costly as only a few laboratories have the unique capabilities. Recently, Code Case 2938 was accepted in ASME Boiler and Pressure Vessel Code (BPVC) VIII-3 allowing for design curves to be used in lieu of performing fatigue crack growth rate (da/dN vs. ΔK) and fracture threshold (KIH) testing in hydrogen gas. The design curves were based on data generated at 100 MPa H2 on SA-372 and SA-723 grade steels; however, the data used to generate the design curves are limited to measurements of ΔK values greater than 6 MPa m1/2. The design curves can be extrapolated to lower ΔK (< 6 MPa m1/2), but the threshold stress intensity factor (ΔKth) has not been measured in hydrogen gas. In this work, decreasing ΔK tests were performed at select hydrogen pressures to explore threshold (ΔKth) for ferritic-based structural steels (e.g. pipelines and pressure vessels). The results were compared to decreasing ΔK tests in air, showing that the fatigue crack growth rates in hydrogen gas appear to yield similar or even slightly lower da/dN values compared to the curves in air at low ΔK values when tests were performed at stress ratios of 0.5 and 0.7. Correction for crack closure was implemented, which resulted in better agreement with the design curves and provide an upper bound throughout the entire ΔK range, even as the crack growth rates approach ΔKth. This work gives further evidence of the utility of the design curves described in Code Case 2938 of the ASME BPVC VIII-3 for construction of high pressure hydrogen vessels.

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Crack Growth Analysis of High-Pressure Equipment for Hydrogen Storage

Volume 1B: Codes and Standards ◽

10.1115/pvp2013-97272 ◽

2013 ◽

Author(s):

Z. Y. Li ◽

C. L. Zhou ◽

Y. Z. Zhao ◽

Z. L. Hua ◽

L. Zhang ◽

...

Keyword(s):

High Pressure ◽

Hydrogen Storage ◽

Crack Growth ◽

Growth Analysis ◽

Model Material ◽

Hydrogen Gas ◽

Cycle Life ◽

Cold Worked ◽

Type 304 ◽

Pressure Hydrogen

Crack growth analysis (CGA) was applied to estimate the cycle life of the high-pressure hydrogen equipment constructed by the practical materials of 4340 (two heats), 4137, 4130X, A286, type 316 (solution-annealed (SA) and cold-worked (CW)), and type 304 (SA and CW) in 45, 85 and 105 MPa hydrogen and air. The wall thickness was calculated following five regulations of the High Pressure Gas Safety Institute of Japan (KHK) designated equipment rule, KHKS 0220, TSG R0002, JB4732, and ASME Sec. VIII, Div. 3. We also applied CGA for four typical model materials to discuss the effect of ultimate tensile strength (UTS), pressure and hydrogen sensitivity on the cycle life of the high-pressure hydrogen equipment. Leak before burst (LBB) was confirmed in all practical materials in hydrogen and air. The minimum KIC required for LBB of the model material with UTS of even 1500 MPa was 170 MPa·m0.5 in 105 MPa. Cycle life qualified 103 cycles for all practical materials in air. In 105 MPa hydrogen, the cycle life by KIH was much shorter than that in air for two heats of 4340 and 4137 sensitive to hydrogen gas embrittlement (HGE). The cycle life of type 304 (SA) sensitive to HGE was almost above 104 cycles in hydrogen, while the cycle life of type 316 (SA and CW) was not affected by hydrogen and that of A286 in hydrogen was near to that in air. It was discussed that the cycle life increased with decreasing pressure or UTS in hydrogen. This behavior was due to that KIH increased or fatigue crack growth (FCG) decreased with decreasing pressure or UTS. The cycle life data of the model materials under the conditions of the pressure, UTS, KIH, FCG and regulations in both hydrogen and air were proposed quantitatively for materials selection for high-pressure hydrogen storage.

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Fatigue Crack Growth Behavior of Autofrettaged Hydrogen Pressure Vessel Made of Low Alloy Steel

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2017-65907 ◽

2017 ◽

Author(s):

Yoru Wada ◽

Yusuke Yanagisawa

Keyword(s):

High Pressure ◽

Fatigue Crack ◽

Fatigue Crack Growth ◽

Crack Propagation ◽

Crack Growth ◽

Cylindrical Specimen ◽

Growth Behavior ◽

Gaseous Hydrogen ◽

Crack Growth Behavior ◽

Low Alloy Steel

Autofrettage is used to known as an effective method to prevent fatigue crack propagation of thick-walled cylinder vessels operating under high pressure. Since low-alloy steel shows an enhanced crack growth rate in high-pressure gaseous hydrogen, this paper aims to validate the effect of autofrettage on crack growth behavior in high-pressure gaseous hydrogen utilizing 4%NiCrMoV steel (SA723 Gr3 Class2). An autofrettaged cylindrical specimen with a 70mm inside diameter and 111mm outside diameter was prepared with an axial EDM (depth of 1mm) notched on the inside surface. The measured residual stress profile coincides well with the calculated results. The fatigue crack growth test was conducted by pressurizing the cylinder and varying the external water pressure. Crack propagation from the EDM notch was observed in the non-autofrettaged cylindrical specimen while no crack propagation was observed when the initial EDM notch size was within the compressive residual stress field. When the initial EDM notch size was increased, the fatigue crack growth showed a narrow, groove-like fracture surface for the autofrettaged specimen. In order to qualitatively analyze those results, fatigue crack growth rates were examined under various load ratios including a negative load ratio using a fracture mechanics specimen. From the information obtained, crack growth analysis of an autofrettaged cylinder in a high-pressure hydrogen environment was successfully demonstrated with a fracture mechanics approach.

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Mechanical Properties of a New Nitrogen-Strengthened Stainless Steel With Reduced Amount of Ni and Mo in High Pressure Gaseous Hydrogen

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2013-97656 ◽

2013 ◽

Author(s):

Kazuhisa Matsumoto ◽

Shinichi Ohmiya ◽

Hideki Fujii ◽

Masaharu Hatano

Keyword(s):

High Pressure ◽

Stainless Steel ◽

Fatigue Crack ◽

Fatigue Crack Growth ◽

Crack Growth ◽

High Strength ◽

Hydrogen Gas ◽

Fracture Surfaces ◽

Growth Properties ◽

Pressure Hydrogen

To confirm a compatibility of a newly developed high strength stainless steel “NSSC STH®2” for hydrogen related applications, tensile and fatigue crack growth properties were evaluated in high pressure hydrogen gas up to 90MPa. At temperatures between −40 and 85°C, no conspicuous deterioration of tensile properties including ductility was observed even in 90 MPa hydrogen gas at −40°C while strength of STH®2 was higher than SUS316L. Although a slight drop of reduction of area was recognized in one specimen tested in 90 MPa hydrogen gas at −40°C, caused by the segregation of Mn, Ni and Cu in the laboratory manufactured 15mm-thick plate, it was considerably improved in the large mill products having less segregation. Fatigue crack growth rates of STH®2 in high pressure hydrogen gas were almost the same as that of SUS316L in air. Although fatigue crack growth rate in air was considerably decelerated and lower than that in hydrogen gas at lower ΔK region, this was probably caused by crack closure brought by oxide debris formed on the fracture surfaces near the crack tip by the strong contact of the fracture surfaces after the fatigue crack was propagated. By taking the obtained results into account, it is concluded that NSSC STH®2 has excellent properties in high pressure hydrogen gas in addition to high strength compared with standard JIS SUS316L.

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On Material Qualification and Strength Design for Hydrogen Service

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2015-45723 ◽

2015 ◽

Author(s):

Junichiro Yamabe ◽

Hisao Matsunaga ◽

Yoshiyuki Furuya ◽

Saburo Matsuoka

Keyword(s):

High Pressure ◽

Fatigue Crack ◽

Fatigue Crack Growth ◽

Crack Growth ◽

Safety Factor ◽

Fatigue Testing ◽

Hydrogen Gas ◽

Multiplier Method ◽

Notched Specimens ◽

Pressure Hydrogen

To clarify the usefulness of the safety factor multiplier method for hydrogen components given in the CHMC1-2014 standard, we performed slow-strain-rate tensile and fatigue testing by using smooth and notched specimens in air and in high-pressure hydrogen gas. We also conducted fatigue-crack growth tests by using compact tension specimens in air and in hydrogen gas. Testing of notched specimens sampled from a Cr–Mo steel gave a safety factor multiplier of 3.0. This value agreed well with that predicted by crack growth analysis taking into account hydrogen-enhanced fatigue-crack growth. The safety factor multipliers of types 304, 316, and 316L austenitic stainless steels were predicted to be 2.0, 1.6, and 1.3, respectively, from their fatigue-crack growth behaviors. The safety factor based on the safety factor multiplier method seems to be overly conservative for the various steels in high-pressure hydrogen gas service. We therefore propose a new and promising design method for specific component applications that is based on design by rule and design by analysis. The importance of operational histories of components for hydrogen service is introduced to permit the precise prediction of their fatigue lives.

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Materials Safety for Hydrogen Gas Embrittlement of Metals in High-Pressure Hydrogen Storage for Fuel Cell Vehicles

Volume 1: Codes and Standards ◽

10.1115/pvp2012-78269 ◽

2012 ◽

Cited By ~ 1

Author(s):

L. Zhang ◽

M. Wen ◽

Z. Y. Li ◽

J. Y. Zheng ◽

X. X. Liu ◽

...

Keyword(s):

High Pressure ◽

Fuel Cell ◽

Hydrogen Storage ◽

Crack Growth ◽

Hydrogen Gas ◽

Materials Testing ◽

Fuel Cell Vehicles ◽

Growth Data ◽

Type Iii ◽

Pressure Hydrogen

Materials safety and selection for the application of metals in high-pressure hydrogen storage of fuel cell vehicles were introduced based on the hydrogen gas embrittlement (HGE) examinations using the materials testing equipment. Testing steps are as follows; the 1st step is the tensile test in high-pressure hydrogen by slow strain rate technique to evaluate the effect of hydrogen and divide the materials into five categories based on stress-strain curves. The materials of type III, IV and V are picked up and their yield points and ultimate tensile strengths are collected. The 2nd step is the fracture mechanics test to obtain KICs and KIHs of type III, IV and V materials. The materials of type IV and V are considered to be applicable as usual. The 3rd step is the crack growth test to obtain the fatigue crack growth data. A special consideration of HGE is taken for the design of the equipment with limited operation period or cycles for the materials of type III. The issue of the Kth’s reproducibility remains unresolved, which calls another testing method and design concept. Candidate materials are then nominated following the procedure of materials selection.

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