抗拉强度1100MPa以上高强度气瓶的研究

Research on High Strength Cylinders with Tensile Strength above 1100 MPa

通过研究抗拉强度1100 MPa以上高强度气瓶钢,采用ISO 9809-2:2010壁厚计算公式和有限元技术,对ф229 mm,50 L高强度气瓶进行了设计与分析;并通过"未爆先漏(LBB)"试验对设计进行了验证。结果表明,34CrMo4H高强度气瓶钢在870℃加热、水介质冷却淬火、570~600℃回火空冷热处理条件下,能够满足1100 MPa以上高强度气瓶的设计要求;高强度气瓶的壁厚设计按照ISO 9809-2:2010公式是合理的,但凹底厚度应结合有限元技术进行分析确定,不能直接取值为2倍最小设计壁厚;与GB 5099—1994标准设计相比,高强度气瓶的空瓶质量降低20%以上,实现了气瓶的轻量化,并大大提高了气体充装量;预制裂纹疲劳试验次数在11000次左右,疲劳寿命接近完好气瓶规定值12000次的水平。预制裂纹爆破试验表明,当采用爆破试验方法时预制裂纹深度为实际壁厚的75%左右,当采用疲劳试验方法时预制裂纹深度为实际壁厚的60%~70%,试验结果均能够满足设计要求。

Through studying the high strength steel with the tensile strength above 1100 MPa. The design and analysis of φ229 ram,50 L high strength cylinders are made by wall thickness formula from ISO 9809 -2：2010 and finite element technology. Finally, the design was verified by the leak-before-break （LBB） test. The results show that the 34CrMo4H high strength gas cylinder steel can meet the design requirements of high strength gas cylinders under the heat treatment conditions of 870℃ heating, water medium cooling quenching, tempering and air cooling at 570 - 600 ℃. The wall thickness design of high strength cylinder in accordance with the wall thickness formula from ISO 9809 -2：2010 is reasonable, But the thickness of base should be analyzed with the finite element technique,which can not be directly taken as 2 times of the minimum design wall thickness. Compared with the GB 5099--1994 standard, the empty cylinder weight of the high strength cylinder is reduced by more than 20% and greatly raised gas filling weight, re- alizing the lightweight of cylinders. The number of fatigue crack test is about 11000 times. The fatigue life is close to the level of 12000 times of the intact cylinder. For the pre-existing crack blasting test, when the test method of blasting pre-existing crack depth for the actual wall thickness of about 75 %, when the test method of fatigue pre-existing crack depth for the actual wall thickness of 60% - 70%, the test results are in agreement with standard. ~