Theoretical Research on Circumferential Stress of Four-point Bending Specimen of Unequal Thickness

doi:10.11885/j.issn.1674-5086.2018.08.30.03

Abstract

Abstract: Straight beam specimens of equal thickness, which are standard four-point bending specimens, cannot be used to simulate the real working condition of the curved-beam structure of pipes. Therefore, a non-standard four-point bending specimen of unequal thickness was designed, which has a complete arc as the outer wall and a straight-line segment combined with two symmetrical arcs as the inner wall. Based on the structure and mechanical model of a four-point bending specimen with unequal thickness, a theoretical formula to calculate the circumferential tensile stress at any arbitrary point on the specimen's outer wall from the load of the specimen was derived. Further, a finite element mechanics calculation model for this four-point bending specimen was established. The results show that the absolute error of the maximum circumferential stress calculated by the theoretical formula derived in the paper was 0.06%~0.33% compared to the result by the finite element method. This indicates that there is almost no error, which fully proves the accuracy of the theoretical formula. The theoretical formula provides a simple method for calculating load parameters of stress-corrosion cracking experiments with the four-point bending specimen of unequal thickness.

Key words: unequal thickness, four-point bending specimen, theoretical formula derivation, finite element, stress corrosion cracking

CLC Number:

TE98

LIAN Zhanghua, ZHANG Jin, WANG Yuhai, ZHANG Qiang, LIU Yonggang. Theoretical Research on Circumferential Stress of Four-point Bending Specimen of Unequal Thickness[J]. 西南石油大学学报(自然科学版), 2020, 42(1): 161-169.

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References

[1] 杨鹏博. 天然气管道输送与管理[J]. 化学工程与装备,2018(4):66-67. doi:10.19566/j.cnki.cn35-1285/tq.2018.04.025 YANG Pengbo. Natural gas pipeline transportation and management[J]. Chemical Engineering & Equipment, 2018(4):66-67. doi:10.19566/j.cnki.cn35-1285/tq.2018.04.025
[2] 黄国建,徐烽,郭惠久,等. 鞍钢X60管线钢热轧卷板的研制与应用[J]. 鞍钢技术,2004(5):17-20,25. doi:10.3969/j.issn.1006-4613.2004.05.005 HUANG Guojian, XU Feng, GUO Huijiu, et al. Study on X60 pipeline steel hot rolled coiled sheet and its application in Angang[J]. Angang Technology, 2004(5):17-20, 25. doi:10.3969/j.issn.1006-4613.2004.05.005
[3] ZVIRKO O I, SAVULA S F, TSEPENDA V M, et al. Stress corrosion cracking of gas pipeline steels of different strength[J]. Procedia Structural Integrity, 2016, 2:509-516. doi:10.1016/j.prostr.2016.06.066
[4] 蒲前梅,王志华. 原油长输管道安全防护技术浅析[J]. 油气田地面工程,2009,28(11):63-65. doi:10.3969/j.issn.1006-6896.2009.11.037 PU Qianmei, WANG Zhihua. Simple analysis of safeguard technology in long distance oil transportation pipeline[J]. Oil-Gasfield Surface Engineering, 2009, 28(11):63-65. doi:10.3969/j.issn.1006-6896.2009.11.037
[5] 吕祥鸿,赵国仙,张建兵,等. 用于集输管线的0.5 Cr钢在模拟塔里木油田环境中的H₂S/CO₂腐蚀行为研究[J]. 石油学报,2009,30(5):782-787. doi:10.3321/j.issn:0253-2697.2009.05.028 LÜ Xianghong, ZHAO Guoxian, ZHANG Jianbing, et al. Experimental study on corrosion behaviors of H₂S and CO₂ to 0.5 Cr steel used in gathering pipeline at simulated environment of Tarim Oilfield[J]. Acta Petrolei Sinica, 2009, 30(5):782-787. doi:10.3321/j.issn:0253-2697.2009.05.028
[6] XU Shugen, HUANG Shengjun, GUO Deguo, et al. Failure analysis of a carbon steel pipeline exposed to wet hydrogen sulfide environment[J]. Engineering Failure Analysis, 2017, 71:1-10. doi:10.1016/j.engfailanal.2016.11.001
[7] MERESHT E S, FARAHANI T S, NESHATI J. Failure analysis of stress corrosion cracking occurred in a gas transmission steel pipeline[J]. Engineering Failure Analysis, 2011, 18(3):963-970. doi:10.1016/j.engfailanal.2010.11.014
[8] 高立新,谷坛,闫静,等. 高酸性条件下元素硫对碳钢腐蚀的影响[J]. 天然气工业,2015,35(4):94-98. doi:10.3787/j.issn.1000-0976.2015.04.015 GAO Lixin, GU Tan, YAN Jing, et al. Corrosion of sulfur to carbon steel under the condition of high acidity[J]. Natural Gas Industry, 2015, 35(4):94-98. doi:10.3787/j.issn.1000-0976.2015.04.015
[9] 雷晓曾,张阳. 天然气长输管道运行管理中易发问题及综合治理浅析[J]. 内蒙古石油化工,2015,41(15):90-93. doi:10.3969/j.issn.1006-7981.2015.15.035 LEI Xiaozeng, ZHANG Yang. Common problems in the operation and management of long-distance natural gas transmission pipelines and comprehensive control analysis[J]. Inner Mongolia Petrochemical Industry, 2015, 41(15):90-93. doi:10.3969/j.issn.1006-7981.2015.15.035
[10] 王一龙,杨平希. 在役油气管道应力腐蚀开裂及其防护措施[J]. 山东化工,2019,48(5):116-117,121. doi:10.3969/j.issn.1008-021X.2019.05.043 WANG Yilong, YANG Pingxi. Stress corrosion cracking and the corresponding protective measures in natural oil and gas pipeline[J]. Shandong Chemical Industry, 2019, 48(5):116-117, 121. doi:10.3969/j.issn.1008-021X.2019.05.043
[11] 吕祥鸿,赵国仙,王宇,等. 超级13Cr马氏体不锈钢抗SSC性能研究[J]. 材料工程,2011(2):17-21,25. doi:10.3969/j.issn.1001-4381.2011.02.004 LÜ Xianghong, ZHAO Guoxian, WANG Yu, et al. SSC resistance of super 13Cr martensitic stainless steel[J]. Journal of Materials Engineering, 2011(2):17-21, 25. doi:10.3969/j.issn.1001-4381.2011.02.004
[12] 张锁龙,尤一匡,黄志荣,等. 低碳钢含裂纹管道四点弯曲作用下弹塑性裂纹扩展的试验研究[J]. 压力容器,1999(2):12-16. ZHANG Suolong, YOU Yikuang, HUANG Zhirong, et al. Experimental study on carbon-steel pipe containing a circumferential through-wall crack under four points bending[J]. Pressure Vessel Technology, 1999(2):12-16.
[13] 鲜宁,姜放,赵华莱,等. H₂S/CO₂环境下析出相对28合金耐SCC性能的影响[J]. 天然气工业,2010,30(4):111-115. doi:10.3787/j.issn.1000-0976.2010.04.027 XIAN Ning, JIANG Fang, ZHAO Hualai, et al. Effect of precipitates on SCC resistance of the Ni-based alloy 28 in H₂S and CO₂ service conditions[J]. Natural Gas Industry, 2010, 30(4):111-115. doi:10.3787/j.issn.1000-0976.2010.04.027
[14] NORDMANN J, THIEM P, CINCA N, et al. Analysis of iron aluminide coated beams under creep conditions in high-temperature-four-point-bending tests[J]. The Journal of Strain Analysis for Engineering Design, 2018, 53(4):255-265. doi:10.1177/0309324718761305
[15] 张慧芳,肖振兴,肖少彬,等. 奥氏体钢四点弯曲疲劳行为的数值模拟与试验[J]. 钢铁,2017,52(4):61-66. doi:10.13228/j.boyuan.issn0449-749x.20160351 ZHANG Huifang, XIAO Zhenxing, XIAO Shaobin, et al. Numerical simulation and experimental on four-point bending fatigue behavior of austenite steel[J]. Iron & Steel, 2017, 52(4):61-66. doi:10.13228/j.boyuan.issn0449-749x.20160351
[16] 孙宝瑞,马伟,杨秀光. 海洋管道四点弯曲疲劳试验机夹具设计和有限元分析[J]. 工程与试验,2017,57(2):67-72. doi:10.3969/j.issn.1674-3407.2017.02.019 SUN Baorui, MA Wei, YANG Xiuguang. Fixture design and finite element analysis of submarine pipeline four-point bending fatigue testing machine[J]. Engineering & Test, 2017, 57(2):67-72. doi:10.3969/j.issn.1674-3407.2017.02.019
[17] 刘裕,刘小妹,胡磊,等. 四点弯曲U形切口应力集中系数的数值分析[J]. 上海工程技术大学学报,2014,28(2):141-144. doi:10.3969/j.issn.1009-444X.2014.02.011 LIU Yu, LIU Xiaomei, HU Lei, et al. Numerical analysis of stress concentration factors for u-shaped notch with four-point bending[J]. Journal of Shanghai University of Engineering Science, 2014, 28(2):141-144. doi:10.3969/j.issn.1009-444X.2014.02.011
[18] DONG Xiaolong, ZHAO Hongwei, ZHANG Lin, et al. Geometry effects in four-point bending test for thin sheet studied by finite element simulation[J]. Materials Transactions, 2016, 57(3):335-343. doi:10.2320/matertrans.M2015178
[19] ARUN S, SHERRY A H, SMITH M C, et al. Simulations of the large-scale four point bending test using Rousse、-lier model[J]. Engineering Fracture Mechanics, 2017, 178:497-511. doi:10.1016/j.engfracmech.2017.02.015
[20] AURÉ LIEN D, LEGUILLON D. 3D application of the coupled criterion to crack initiation prediction in epoxy/aluminum specimens under four point bending[J]. International Journal of Solids & Structures, 2018, 143:175-182. doi:10.1016/j.ijsolstr.2018.03.005
[21] 鲜宁,姜放,荣明,等. 四点弯曲加载下带焊缝试样表面的最大拉应力公式推导与分析[J]. 理化检验(物理分册),2010,46(7):415-418. XIAN Ning, JIANG Fang, RONG Ming, et al. Deducing and analyzing for maximum tensile stress formula of weld specimen loaded by four-point-bending[J]. Physical Testing and Chemical Analysis (Part A:Physical Testing), 2010, 46(7):415-418.
[22] 全国钢标准化技术委员会. 金属在硫化氢环境中抗硫化物应力开裂和应力腐蚀开裂的实验室试验方法:GB T4157-2017[S]. 北京:中国标准出版社,2017.
[23] 刘鸿文. 材料力学II[M]. 5版. 北京:高等教育出版社,2011. LIU Hongwen. Strength of materials II[M]. 5^th Edition. Beijing:Higher Education Press, 2011.