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1.
《焊接》2015,(10)
针对规格为φ139.70 mm钻杆焊缝区进行横向侧弯试验过程中出现试样断裂情况,通过对断口扫描电镜分析、焊缝区金相检测,结合焊缝区的拉伸试验、洛氏硬度和冲击试验等分析检测手段,查找分析了产生不合格情况的原因。结果表明:因钻杆接头和管体端面残留油污,致使钻杆摩擦焊生产过程中在焊缝生成大量夹杂物,影响钻杆焊缝区力学性能,导致横向侧弯试验不合格。  相似文献   

2.
利用金相显微镜、扫描电镜以及能谱和波谱分析手段详细研究了37CrMnMo4钻杆接头生产过程中的缺陷问题,结果表明,37CrMnMo4钻杆接头组织局部呈过烧状态,自由结晶面周围及晶界熔融处有P、Mo、Cr等元素的偏聚,由于钻杆接头材料中合金元素的偏析导致后续锻造过程中材料发生“形变过烧”。  相似文献   

3.
介绍了淬火机技术的应用,概述了钻杆管体的机械性能和对外形尺寸的要求,提出在V150钢级、SS105抗硫钻杆管体生产时应加大水量,生产Φ193.7 mm规格钻杆管体时注意调整防止淬火后变形。  相似文献   

4.
张毅  赵鹏 《钢管》2003,32(4)
对发生管体刺穿、外壁腐蚀的Ф127mm×9.19mm IEU S-135钻杆进行了失效分析.结果表明,钻杆的化学成分、金相组织、机械性能均符合API标准及订货技术条件.钻杆管体刺穿是由于内壁发生严重H2S腐蚀+氧腐蚀造成的.钻杆管体外壁腐蚀是由氧腐蚀引起的.  相似文献   

5.
Ф127minx9.19mm IEU S-135钻杆腐蚀失效分析   总被引:3,自引:0,他引:3  
张毅  赵鹏 《钢管》2003,32(4):10-16
对发生管体刺穿、外壁腐蚀的Ф127mm×9.19mm IEU S-135钻杆进行了失效分析.结果表明,钻杆的化学成分、金相组织、机械性能均符合API标准及订货技术条件.钻杆管体刺穿是由于内壁发生严重H2S腐蚀+氧腐蚀造成的.钻杆管体外壁腐蚀是由氧腐蚀引起的.  相似文献   

6.
一批钢级为X95的钻杆,在进行钻杆接头摩擦对焊和钻杆管体内表面涂层涂覆处理后,探伤时发现部分钻杆管体存在不同程度的纵向裂纹。通过金相、扫描和能谱分析的手段,对裂纹的形貌和形成原因进行分析,并结合生产工艺过程,对产生裂纹的原因进行追溯。结果表明:钻杆管端磁粉探伤时与电极接触,管体局部粘附了低熔点电极材料,造成了重金属污染,在后续的加工过程中,管体再次受热,粘附其上的重金属元素向管体金属沿着晶界扩散,从而导致了裂纹的形成。  相似文献   

7.
对2010年上半年苏里格地区所发生的钻具失效事故进行了数据收集和统计分析。统计表明,该地区最为常见的钻具失效类型依次为钻杆的疲劳/腐蚀疲劳失效、钻铤螺纹接头的疲劳/腐蚀疲劳失效和钻杆管体过载断裂失效3种。简单分析了导致这3种失效的原因,并提出了有效的预防措施。  相似文献   

8.
对某厂生产的20Mn2钢制φ27 mm×11.5 mm汽车半轴套管进行热处理时发现开裂和断裂,对其进行宏观观察、成分分析和金相分析.结果表明,钢管在热处理过程中,加热温度过高或加热时间过长引起的过烧是导致开裂和断裂的主要原因.  相似文献   

9.
采用宏观、金相、XRD等手段,对N80-1油管在新疆稠油热采井火驱工艺开采过程中断裂的原因进行分析。分析认为:该断裂为过载断裂,导致油管过载断裂的主要原因是火驱过程中原油燃烧温度过高,使油管发生高温软化。原油燃烧生成的高CO_2分压导致CO_2腐蚀严重,腐蚀使管体发生点蚀和壁厚减薄,燃烧过程中钢管表面的高温氧化也导致壁厚减薄,都会加速管体发生过载断裂。指出C-Mn系油管不适合用于稠油热采井火驱开采工艺,建议选用Cr-Mo系调质钢种的稠油热采专用管。  相似文献   

10.
某超深井在下套管过程中发生V150钻杆断裂事故,为查明断裂原因,采用宏观及显微组织分析、硬度测试、线弹性断裂力学分析等方法对断裂样品进行了失效分析。结果表明,该钻杆为脆性断裂,裂纹起源于摩擦对焊焊缝外表面附近的灰斑缺陷。由于钻杆焊缝热处理回火时超温,在较快冷却速度下形成了硬脆相组织,降低了焊缝断裂韧性及裂纹临界尺寸,在裂纹深度达到临界尺寸时,裂纹迅速失稳扩展,导致钻杆脆性断裂。  相似文献   

11.
In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.  相似文献   

12.
After nearly two years' tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry (SRIF), located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.  相似文献   

13.
The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.  相似文献   

14.
On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes' collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.  相似文献   

15.
An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quantitatively estimate the interfacial energy of the nanostructured multilayer films(NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be *5.0 J/m2 for Cu/Cr, *4.1 J/m2 for Cu/Ta,*2.8 J/m2 for Cu/Mo, *1.1 J/m2 for Cu/Nb, and *1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.  相似文献   

16.
A 17 vol% SiCp/Al–Mg–Si–Cu composite plate with a thickness of 3 mm was successfully friction stir welded(FSWed) at a very high welding speed of 2000 mm/min for the first time. Microstructural observation indicated that the coarsening of the precipitates was greatly inhibited in the heat-affected zone of the FSW joint at high welding speed, due to the significantly reduced peak temperature and duration at high temperature. Therefore, prominent enhancement of the hardness was achieved at the lowest hardness zone of the FSW joint at this high welding speed, which was similar to that of the nugget zone. Furthermore, the ultimate tensile strength of the joint was as high as 369 MPa, which was much higher than that obtained at low welding speed of 100 mm/min(298 MPa). This study provides an effective method to weld aluminum matrix composite with superior quality and high welding efficiency.  相似文献   

17.
吴玉梅  熊晓云  靳蓉  孙敬民  杨林  罗晓星 《金属学报》2005,10(10):1100-1103
目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。  相似文献   

18.
On the basis of energy and shape method for the determination of the valence bond (VB) structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is e_c~(2.9907) · (s_c~(0.4980) d_c~(2.4927)) ef1.0093 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K.  相似文献   

19.
During the slab continuous casting process, the flow field of molten steel in the mold plays a decisive role in the quality of the slab. In this paper, electromagnetic swirling flow in nozzle technology is proposed to control the flow field in mold.This technology can drive molten steel to rotate inside the submerged entry nozzle by electromagnetic force, thereby controlling the flow field. This research shows that it can reduce the impact of molten steel on the bottom of nozzle and partly reduce the negative pressure at the upper part of nozzle outlet which is even eliminated by optimizing the structure and angle of nozzle. The area of heat flux of the mold wall becomes larger, and the crest value of heat flux gets lower than that without swirling in nozzle and any nozzle optimization. The meniscus fluctuates smoothly, and the flow velocity at the top surface is within a reasonable range. The temperature field distribution in the mold is uniform which was beneficial to the growth of equiaxed crystal and decreased element segregation.  相似文献   

20.
The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).  相似文献   

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