Analysis of Welding Technology about Bimetallic Clad Pipelines

Butt girth welding was a knotty problem for future application of bimetallic clad pipelines. At present, there were two kinds of problems: 1) To decide whether to use a variety of alloy welding procedure or to use corrosion resistant alloy full welding procedure; 2) After selecting the procedure, what kind of welding material should be equipped. In view of the above problems, taking 316L SS or 2205 DSS clad pipe as an example, welding process design and experimental analysis were conduted in this paper. Analysis of welding process from theory, standard and practice pointed out the control of welding hardness under different welding materials and procedure and directional suggestions of welding for bimetallic clad pipelines were provided. Futher the hardness distribution and CVN absorbed Energy test results of different welding processes showed welding quality could be guaranteed only when ENiCrMo-3 welding material was chosen for the whole weld.

Hopkinson rod test results and constitutive description of TRIP780 steel resistance spot welding material

A quasi-static tensile test was performed on a 1.4 mm-thick TRIP780 steel strip with welding points. An MTS810 material test machine was used in the test, and a Split Hopkinson tension bar device was used in performing impact stretch loading at different strain rates. The dynamic tensile stress–strain curve of the spot welding material with different strain rates was obtained through the finely designed Hopkinson rod test, and the strain rate dependence of a TRIP780 steel spot welding material was discussed. According to the dynamic constitutive equation of the TRIP780 steel spot welding material, the test results were numerically simulated, the constitutive description and test curves were compared, and the simulation results and test results were discussed and analyzed. The fractures of the test recovery specimen were scanned with the scanning electron microscope, and the fracture mechanism of the TRIP780 steel spot welding material was explored by observing the fractures. The surfaces of the fractures surface showed obvious cleavage river patterns, and the evolution process of microcracks was determined and used in characterizing brittle fractures in specimen spot welding sample subjected to dynamic stretch loading.

PENGARUH MODEL PEMBELAJARAN TUTOR SEBAYA TERHADAP HASIL BELAJAR SISWA PADA MATA PELAJARAN TEORI PENGELASAN SHIELD METAL ARC WELDING (SMAW) DI KELAS XI TP LAS SMK NEGERI 3SINGARAJA TAHUN AJARAN 2018/2019

Penelitian ini dilakukan untuk mengetahui Bagaimana Pengaruh Model Pembelajaran Tutor Sebaya Terhadap Hasil Belajar Siswa Pada Mata Pelajaran Pengelasan SMAW Di kelas XI TPLas di SMK Negeri 3 Singaraja Tahun Ajaran 2018/2019. Metode penelitian yang digunakan dalam penelitian ini yaitu dengan desain One-shoot Case Study. Pemilihan sampel pada penelitian ini menggunakan teknik random sampling. Sampel pada penelitian ini sebanyak 34 orang kelas XI TP Las sebagai kelas eksperimen. Setelah pemberian perlakuan berupa penerapan model pembelajaran kooperatif tipe Tutor Sebaya, siswa diberikan tes berupa tes objektif yang sebelumnya sudah dilakukan uji validitas isi, validitas butir, tingkat kesukaran, daya beda dan reliabilitas. Setelah didapatkan data, kemudian dilakukan analisis menggunakan uji-t satu pihak. Hasil penelitian menunjukan bahwa terdapat pengaruh model pembelajaran Tutor Sebaya terhadap hasil belajar Teori pengelasan SMAW siswa kelas XI TPLas I di SMK Negeri 3 Singaraja. Hal ini ditunjukan dengan hasil uji-t dengan t-hitung =37,96, dk= n-1 =33, dan taraf signifikan 5% didapat t tabel=2,0345. Dengan demikian t_tabel < t_hitung, maka H_0 ditolak dan H_1 diterima dan berarti terdapat pengaruh yang signifikan model pembelajaran Tutor Sebaya terhadap hasil belajar Teori pengelasan SMAW siswa kelas XI TP Las I di SMK Negeri 3 Singaraja Tahun Aaran 2018/2019. Kata Kunci : Metode Pembelajaran Tutor Sebaya, Hasil Belajar, One-shoot Case study. This study aimed in investigating the effect of pair to pair method towards the students' achievement in SMAW welding material in grade XI students of SMK Negeri 3 Singaraja. The method used in thia study is one shoot case study. This study used random sampling method. There were 34 studens grade XI TP Las I as experimenting class. After giving the treatment using pair to pair method, the students were given the test in the form of objective test which has been validated in terms of essence validation, grain validation, the stage of difficulty, effort difference, and reliability. After the data were gathered, then those were analized by using one side t-test. The result shows the pair to pair method gives significant effect towards the students' achievements. This can be seen from the resultnof the t-test with t-count= 37.96 dk= n-1= 33 with the significant degree =5% t-table gained =2.0345. Then t- count is higher than t-table, so that H0 is rejected and H1 is accepted, which means there is a significant effect from pair to pair method towards the students' achievements of grade XI students of SMK Negeri 3 Singarajakeyword : Pair to pair, Students' Achievements, One shoot case study

A NEW WELDING MATERIAL FOR REGENERATION IN THE WELDING TECHNOLOGY BASED ON NICKEL. DEVELOPMENT OF A NEW HIGH-TEMPERATURE AND CORROSION-RESISTANT WELDING MATERIAL FOR THE REGENERATION OF DEFECTS IN HNA CASTINGS. ANALYSIS OF EXISTING FUELLING STATIONS TYPES AND VEHICLES USING HYDROGEN, HYDROGEN PRODUCTION AND STORING METHODS

This work involves an analysis of high-chromium high-temperature deformable wieldable nickel alloys for use in GTE repair assemblies. It is shown that the alloys EP868 (VZh98) and Haynes 230 can be used in welded assemblies with an operating temperature of 800-1100 °C. The alloys Nimonic 81, Nimonic 91, IN 935, IN 939, and Nicrotan 2100 GT also have a high potential for use in welded assemblies. They are characterized by a combination of good weldability, high-temperature strength, and resistance to scaling. There have been conducted studies on high-temperature salt corrosion of model nickel alloys. They allowed establishing the patterns of the impact of base metal alloying with chromium, aluminum, titanium, cobalt, tungsten, molybdenum, niobium, tantalum and rare earth metals on the critical temperature of the start of salt corrosion Tcor and the alloy mass loss. It has been established that alloys with a moderate concentration (13-16%) of chromium can possess satisfactory hightemperature corrosion resistance (HTC resistance) under the operating conditions of ship GTE. The HTC resistance of CrAl-Ti alloys improves upon reaching the ratio Ti/Al ˃ 1. Meanwhile, the ratio Ti/Al ˂ 1 promotes the formation of corrosion products with low protective properties. The positive effect of tantalum on the HTC resistance of alloys is manifested at higher test temperatures than that of titanium, and the total content of molybdenum and tungsten in alloys is limited by the condition 8Mo2 – 2W2 = 89. The presence of refractory elements stabilizes the strengthening phase and prevents formation of the ɳ-phase. However, their excess promotes formation of the embrittling topologically close packed (TCP) phases and boundary carbides of an unfavorable morphology. Based on the studies of the HTC resistance, there has been identified a class of model high-temperature corrosionresistant nickel alloys with a moderate or high chromium content (30%), Ti/Al ˃ 1, and a balanced content of refractory and rare-earth elements.