色呦呦网址在线观看,久久久久久久久福利精品,国产欧美1区2区3区,国产日韩av一区二区在线

Carbide sealing rings are usually made of WC-Ni carbide, due to its high hardness, bending strength, excellent wear resistance, toughness, and rigidity, does not emit radiation under neutron irradiation. As a result, it can be employed for mechanical sealing in conditions involving high temperature, high pressure, high rotational speeds, corros ive media, solid particle-laden media, and radioactive environments. WC-Ni carbide has found extensive application in fields such as axle seals in vehicle transmission systems, power shift transmissions, specialized pumps for demanding conditions, aircraft rotary seals, petrochemical industries, and nuclear power sealing.

We found that after approximately 80 hours of operation, there were numerous cracks on sealing rings’surface. Continuing to use it could lead to seal failure and result in significant economic losses. Therefore, it is necessary to conduct damage analysis and safety assessment to address this issue.

 

Test Materials and Methods

Test Materials

The test specimens were taken from the WC-Ni carbidesealing ring, designated as YWN8. The inner diameter of the sealing ring is 277 mm, the outer diameter is 302 mm, and the thickness is 20 mm, as shown in Figure 1. The primary material of the sealing ring is WC-Ni carbide, with a WC mass fraction of 89% and a Ni mass fraction of 11%. The mechanical properties of the WC-Ni carbide?are presented in Table 1.

How is?the Metal?Damage on?Carbide?Sealing Ring Formed? 1

How is?the Metal?Damage on?Carbide?Sealing Ring Formed? 2

Test method

Figure 1(a) depicts a solid view of the damaged sealing ring, which features 9 sets of groove weirs/barricades structures. As indicated by the labels 1 to 9 in Figure 1(b), the test is organized based on the distribution of groove weir areas in the sealing ring, dividing them into 9 groups. Further, these 9 groups are subdivided into 18 smaller regions. Upon magnified observation using a microscope, it was observed that 6 of these regions exhibited surface cracks: namely, 2-2, 3-2, 4-2, 5-2, 6-2, and 7-2, whereas the remaining regions showed no cracks on their surfaces.

For analysis, the test selected the areas of the damaged sealing ring where cracks appeared on the sealing surface. Subsequent steps involved surface residual stress testing, microscopic analysis of the damaged sealing ring’s microstructure, and identifying the reasons behind the appearance of cracks on the sealing ring’s surface.

 

Results and Analysis

Microscopic Analysis of the Damaged Area

Based on microscopic observations, the 6-2 damaged region exhibited the highest number of cracks. As shown in Figure 2, the SEM morphology of the 6-2 damaged region specimen reveals that there are a total of 5 cracks in the damaged zone. The origins of these cracks are at the junction between the groove weir and the barricade of the sealing ring. Each crack exhibits a trend of expansion along its length.

sealing ring

Analysis Using White Light Interferometer

Based on the SEM analysis mentioned above, it was found that although the crack volume was significant, the cracking depth was relatively shallow. To further investigate the damage characteristics during the sealing ring’s service, white light interferometry (Bruker Contour GT 3D white light interferometer) testing and analysis were performed on the damaged area of the sealing ring.

Figures 3 and 4 respectively depict the three-dimensional morphology at the location of the largest crack and the two-dimensional profile of the deepest point of the crack in the 6-2 damaged region. The results reveal that the roughness of the groove weir area is approximately 0.672 μm, the roughness of the barricade area is about 0.294 μm, and the height difference between the groove weir area and the barricade area is approximately 2.43 μm. The maximum width of the crack is around 126.4 μm, with a maximum length of about 2.75 mm. During testing, the maximum depth of the crack was found to be around 58.84 μm, while the depths of other crack regions were relatively smaller.

How is?the Metal?Damage on?Carbide?Sealing Ring Formed? 3

Chemical Composition Analysis of the Damaged Area

Energy-Dispersive X-ray Spectroscopy (EDS) Analysis

Based on the microscopic morphology analysis of the mentioned cracks, energy-dispersive X-ray spectroscopy (EDS) was used to analyze the chemical composition of points A, B, and C (corresponding to the specimen matrix, crack area, and the boundary strip between the groove weir and the barricade) as indicated in Figure 2. This was done to determine whether there had been any changes in material composition. The results are shown in Figures 5 to 7.

It can be observed that the specimen matrix primarily contains C, O, Ni, and W. In the crack area, in addition to the aforementioned four main elements, there are also impurity elements such as Cu, Fe, and Ti. This suggests that element transitions occurred in the sealing ring’s mating parts during service, resulting in impurity elements on its surface. The oxygen content in the crack area is significantly higher than that in the matrix, indicating the presence of oxides within the crack area and the occurrence of oxidative wear. Similarly, at the boundary strip between the groove weir and the barricade, in addition to the four main matrix elements, there are trace amounts of impurity elements such as Ti, Fe, and Zr. The damage situation here is similar to the crack area, with the presence of oxidative wear phenomena.

How is?the Metal?Damage on?Carbide?Sealing Ring Formed? 4

How is?the Metal?Damage on?Carbide?Sealing Ring Formed? 5

Electron Probe Microanalysis (EPMA) Analysis

To further investigate the extent of damage to the sealing ring and the characteristics of the cracked area, and to analyze the distribution of chemical composition in the damaged area of the sealing ring, electron probe microanalysis (EPMA) was employed to perform surface analysis on the cracked area within the box shown in Figure 8. Based on the EDS analysis results mentioned above, it was established that oxidative wear occurred during the service of the sealing ring. Therefore, four elements—C, W, Ni, and O—were selected for EPMA surface analysis of the test specimen.

Figure 9 presents the EPMA surface analysis results of the specimen. It can be observed that within the cracked area, there is a relatively higher distribution of C and O compared to the matrix, while the distribution of W within the cracked area is relatively lower compared to the matrix. On the other hand, the distribution of Ni within the cracked area does not exhibit significant differences compared to the matrix. It can be inferred that there is a mild level of oxidation within the cracked area, with the primary oxidation product being oxide of W.

How is?the Metal?Damage on?Carbide?Sealing Ring Formed? 6

How is?the Metal?Damage on?Carbide?Sealing Ring Formed? 7

Surface Residual Stress Analysis

To investigate the surface stress distribution of the sealing ring after service, a portable X-ray residual stress tester was used to conduct residual stress testing on the entire end face of both an unused C# sealing ring and a D# sealing ring (with cracks on the surface) that had been in service for 80 hours. The test positions and their results are shown in Figure 10. It can be observed that unevenly distributed surface residual stress can lead to cracks in the sealing ring. During service, residual stress is released due to friction, resulting in crack formation and failure of the sealing ring.

As shown in Figure 11, the residual stress gradually decreases along the radial direction of the sealing ring from the outer ring to the inner ring, transitioning directly into compressive stress in the barricade area. The stress value at the end of the groove weir area is higher than at the beginning (counter-clockwise along the sealing ring). Observed cracks are all located at the end of the groove weir area, indicating that the stress difference between the beginning and end of this area is relatively low compared to the stress difference between the arc ends. This difference in stress is insufficient to cause damage to the sealing ring.

 

How is?the Metal?Damage on?Carbide?Sealing Ring Formed? 8

How is?the Metal?Damage on?Carbide?Sealing Ring Formed? 9

 

 

 

Conclusione

(1) The majority of crack sources are located at the junction between the groove weir and the barricade of the sealing ring. Most cracks are distributed in the barricade area, where the extent of damage is greater compared to the groove weir area.

(2) Oxidative wear occurred in the damaged area of the sealing ring during service, primarily resulting in oxide products of tungsten (W). The oxidation is relatively mild.

(3) Due to a significant stress difference between the groove weir and the barricade areas of the sealing ring, material damage is prone to occur during service, leading to the initiation of microscopic cracks.

(4) The cracks are relatively shallow, and the damage to the sealing ring is minor. This will not have an immediate impact on operational safety within the short term.

How is?the Metal?Damage on?Carbide?Sealing Ring Formed? 10

 

 

 

 

Lascia un commento

Il tuo indirizzo email non sarà pubblicato. I campi obbligatori sono contrassegnati *

免费国产精品黄色一区二区-日本熟女五十路六十路熟女-国产日韩欧美另类在线综合-亚洲一区二区中文字幕无线乱码| 欧美日韩激情片在线观看-色男人天堂网在线观看-亚洲一级特黄大片免色-国产十八禁免费在线观看| 最近中文字幕国产精品-国产一级片黄片免费观看-日本一区二区三区日韩欧美-亚洲一区电影网站在线观看| 国产二区三区视频在线观看-四虎精品一区二区在线观看-国产中文字幕一区二区视频-精品一区二区三区av在线| 国产精彩自拍视频在线-岛国视频免费在线播放-91久久精品国产综合另类专区-午夜福利欧美激情福利| 午夜亚洲国产色av天堂-色天天综合色天天久久191-国产精品久色婷婷不卡-日韩欧美中文字幕在线韩| 日本人妻中文字幕有码视频-男女啪啪视频免费观看一区-青青草原综合在线视频-极品人妻少妇精品一区二区| 九九热在线精品视频免费-日韩高清免费在线视频-熟女快要高潮了在线观看-亚洲午夜福利视频一级| 热99在线视频免费观看-日本老男人同性恋黄色.-精品国产一区二区三区四不卡在线-久亚洲一线产区二线产区三线麻豆| 国产成人综合激情婷婷-亚洲国产综合在线观看不卡-色综网久久天天综合狼人-亚洲av高清在线不卡| 岛国精品一区二区三区-国产一区二区三区观看不卡av-四虎三级在线视频播放-亚洲乱妇熟女爽到高潮| 国内自拍偷拍视频91-日本成人熟女一区二区三区-国产l精品国产亚洲区久久-久久精品成人中文字幕| 亚洲日本精品国产第一区二区-国产一级二级三级大胆视频-片黄片色日韩在线观看免费-五月综合婷婷中文字幕| 婷婷精品国产亚洲av不片-色播放视频在线观看视频在线播放-色综合91久久精品中文字幕-午夜视频网一区二区三区| 美女脱内衣内裤露出咪咪-美女一区二区三区免费观看-国产网红女主播在线视频-久久亚洲春色中文字幕| 免费十八禁一区二区三区-国产精品一区二区三区99-在线一区二区三区男男视频观看-精品欧美一区二区三区人妖| 京香一区二区三区中文字幕-国内在线精品一区二区三区-久久亚洲精品色噜噜狠狠-亚洲成av人一区二区三区| 日韩精品综合在线一区二区-极品人妻av一区二区三区-激情综合五月中文字幕-欧美免费在线观看黄片| 精品女同一区二区免费播放-四虎成人精品国产永久免费-日韩在线播放av不卡一区二区-久热久草香蕉在线视频| 国产美女高潮久久精品-国产成人精品十八禁在线播放-成在线人视频免费视频-97超级视频在线观看| 中文字幕日韩有码av-麻豆国产成人av高清在线-可以免费观看的av毛片-久久这里只有精品国产亚洲| 日韩国产自拍在线视频-亚洲av午夜激情在线播放-午夜福利你懂的在线观看-少妇特殊按摩高潮惨叫| 久久亚洲中文字幕少妇毛片-91蜜臀精品国产自偷在线-日韩av在线播放天堂网-亚洲在线精品一区二区三区| 在线观看91精品国产性-国产中文字幕精品免费-免费日韩毛片在线观看-精品人妻暴躁一区二区三区| 亚洲乱码中文字幕小综合-欧美亚洲国产精品一区二区-中文字幕人妻系列人妻有码中文-一区二区三区在线观看的视频| 人妻少妇一区二区三区精品-三级尤物视频在线观看-野花在线中文字幕伊人-亚洲精品一区二区播放| 国产一区二区三区精品视频导航-精品国产av网站大全-男女草逼视频网站大全-国内成人在线激情视频| 一区二区三区四区五区黄色-色哟哟精品免费专区在线-很色精品99在线观看-亚洲一区二区三区精品久久| 97视频资源在线观看-国产av天堂久久精品-亚洲av一二三四区又爽又色又爽-悠悠色网视频在线精品| 精品女同一区二区免费播放-四虎成人精品国产永久免费-日韩在线播放av不卡一区二区-久热久草香蕉在线视频| 国产精品高潮呻吟久久av嫩-青青草免费公开在线观看视频-亚洲欧美日韩另类综合视频-国产三级在线观看精品| 传媒精品视频在线观看-久久蜜汁成人国产精品-国产精品伦理视频一区三区-丰满少妇特黄一区二区三区| 精品国产成人亚洲午夜福利-午夜福利一区二区91-亚洲中文字幕女优最新网址-亚洲av成人国产精品| 亚洲国产高清在线一区二区三区-最近免费视频观看在线播放-中出内射视频在线播放-97碰碰日本乱偷人妻禁片| 精品国产一区二区三区吸毒-国产精品一品二区精品网站-偷拍美国美女厕所撒尿-日韩精品在线视频一二三| 成人一区二区三区免费观看-国内久久偷拍精品视频-欧美人与性动α欧美精品z-性感美女勾引男人视频| 亚洲免费视频免费视频-年轻人的性生活免费视频-亚洲国产aa精品一区二区高清-可以免费看的av毛片| 亚洲手机在线视频亚洲毛-欧美91精品国产自产在线-国产一区二区中文字幕在线视频-国产av91在线播放| 国产最新av一区二区-国产精品自产av一区二区三区-国产精品国产三级国产有无不卡-成人偷拍自拍在线观看| 免费十八禁一区二区三区-国产精品一区二区三区99-在线一区二区三区男男视频观看-精品欧美一区二区三区人妖| 91国产自拍视频在线-久久综合婷婷伊人五月天-国产日韩一区二区三区高清视频-日本电影一区二区5566|