scholarly journals KARAKTERISASI MATERIAL BUCKET TEETH PADA EXCAVATOR UNTUK PENINGKATAN KUALITAS DAN PEMBUATAN

INFOMATEK ◽  
2017 ◽  
Vol 18 (2) ◽  
pp. 97
Author(s):  
Buki Tarigan
Keyword(s):  
Material Handling ◽  
Life Time ◽  
Heavy Equipment

Abstrak: Bucket teeth adalah komponen attachment yang sering digunakan pada heavy equipment salah satunya yaitu bucket wheel excavator, yang fungsinya untuk material handling. Prinsip kerja bucket wheel excavator adalah continuous excavators, namun dalam pengoperasinnya bucket teeth sering terjadi kendala yang dapat mengganggu proses produksi. Salah satu kendala yang sering terjadi adalah keausan pada bucket teeth. Bucket teeth harus mempunyai ketangguhan dan kekuatan bahan yang tinggi, sehingga dapatmempengaruhi life time dari komponen tersebut dan mengurangi down time. Dalam penelitian ini akan dibahas mengenai karakterisasi material bucket teeth pada BWE (Bucket wheel excavator) dengan menggunakanmetoda pengamatan metalografi, pengujian komposisi kimia, dan pengujian kekerasan yang berguna untuk mengetahui harga kekerasan pada bucket teeth dengan, demikian dapat memberi informasi kepada industri lokal dan perusahaan yang menggunakan bucket teeth mengenai spesifikasi material yang cocok untuk pembuatan bucket teeth. Adapun hasil pengujian metalografi, analisa komposisi kimia bucket teeth adalah termasuk material baja paduan sedang yang mengandung silicon, mangan dan krom yang mempunyai sifat tangguh, tahan korosi dan tahan aus. Diliahat dari struktur mikro dan kekerasan mempunayai struktur martensit temper dan harga kekerasanya rata-rata 468 BHN. Dengan adanya porositas dan permukaan specimen yang kasar dapat diperkirakan bahwa proses pembuatan bucket teeth menggunakan proses pengecoran (casting), dan diikuti dengan pengerasan (hardening) dan temper

scholarly journals Faktor-Faktor di Industri Galangan Kapal yang Dapat Berkontribusi pada Isu Perubahan Iklim

2019 ◽  
Vol 1 (2) ◽  
pp. 33-40
Author(s):  
Taufik Hidayat
Keyword(s):  
Climate Change ◽  
Material Handling ◽  
Management Strategies ◽  
Monitoring And Evaluation ◽  
Environmental Scanning ◽  
Strategy Formulation ◽  
Shipbuilding Industry ◽  
Heavy Equipment ◽  
The Government

The shipbuilding industry is the fabrication industry in sectors involving the use of heavy equipment materials and manufacturing practices can have an impact on the environment and thus can contribute to climate change. This study reviewed the literature to use the approach can imagine a process that impact on the environment, and occurs in the shipbuilding industry. The hope can give the shipbuilding industry a chance to set a long-term vision on an individual basis, not because in the end was forced to make as a result of coercion by the government or the pressure of the surrounding community, but also address the environmental impact more effectively, and perhaps even get a commercial advantage from the innovations developed. This can be realized with the implementation of management strategies. Management strategy is a series of decisions and managerial actions that determine the long-term performance of the corporation. Where this includes environmental-scanning (external and internal), strategy formulation (planning long-term strategy), strategy implementation, and evaluation and control. So this study emphasizes the monitoring and evaluation of external opportunities and threats on the strengths andweaknesses of the corporation. The results of this study establish a six-facto-a major factor in the shipbuilding industry that can contribute to climate change, namely material handling, metal working, the noise, the government and the surrounding community, the level of technology, and ship recycling.

scholarly journals Perbaikan Sistem Kerja Proses Pemasangan Ban Truk dengan Perancangan Peralatan Pendukung Menggunakan QFD dan REBA

2021 ◽  
Vol 10 (2) ◽  
pp. 161-172
Author(s):  
Hery Hamdi Azwir
Keyword(s):  
Quality Function Deployment ◽  
Material Handling ◽  
Entire Body ◽  
Low Back ◽  
Body Parts ◽  
Heavy Equipment ◽  
Truck Tire ◽  
Medium Risk ◽  
Trauma Disorders ◽  
Awkward Posture

PT.X as one of the heavy equipment manufacturing company are producing mining and non-mining transportation product (e.g. Semi Side Tipper (SST) & Dolly). In producing those kinds of products that mostly using tires, there is a process area to do mounting truck tire. Based on interviews and direct observation results, there is a symptom of Cumulative Trauma Disorders (CTD), especially in the low back area. The low back pain experienced by the operators is caused by an awkward posture that resulted from Manual Material Handling (MMH) in this process. Lifting and holding the tire that is located on the floor with diameter 1.2m, height 0.3m, and weight 90 Kg also the reasons why the awkward posture appears during the mounting truck tire process. Using Rapid Entire Body Assessment (REBA), Nordic Questionnaire, and followed by the Quality Function Deployment (QFD) approach for product design are used to do the improvement for the process. In the end, these ergonomics issues are solved by developing material handling tools that can minimize the risk and symptoms of CTDs. It can be shown by initially REBA score is on level 11 (Very High Risk) to level 7 (Medium Risk) and for the Nordic result from 7 body parts that feel discomfort, now it just becomes 1 body parts feel discomfort.

Microbulldozing and Microchiseling

1969 ◽  
Vol 27 ◽  
pp. 134-135
Author(s):  
J.N. Ramsey ◽  
D.P. Cameron ◽  
F.W. Schneider
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Material Handling ◽  
Microprobe Analysis ◽  
Foreign Matter ◽  
Specific Location ◽  
Potential Problems ◽  
Knoop Indenter ◽  
Scanning Electron ◽  
Microhardness Tester

As computer components become smaller the analytical methods used to examine them and the material handling techniques must become more sensitive, and more sophisticated. We have used microbulldozing and microchiseling in conjunction with scanning electron microscopy, replica electron microscopy, and microprobe analysis for studying actual and potential problems with developmental and pilot line devices. Foreign matter, corrosion, etc, in specific locations are mechanically loosened from their substrates and removed by “extraction replication,” and examined in the appropriate instrument. The mechanical loosening is done in a controlled manner by using a microhardness tester—we use the attachment designed for our Reichert metallograph. The working tool is a pyramid shaped diamond (a Knoop indenter) which can be pushed into the specimen with a controlled pressure and in a specific location.

SEM and Auger microanalysis studies of Cu-Be dynode surfaces at each activation condition

1978 ◽  
Vol 36 (1) ◽  
pp. 524-525
Author(s):  
T. Koshikawa ◽  
Y. Fujii ◽  
E. Sugata ◽  
F. Kanematsu
Keyword(s):  
Electron Emission ◽  
Secondary Electron ◽  
Secondary Electron Emission ◽  
Life Time ◽  
Activation Process ◽  
Beam Diameter ◽  
Activation Temperature ◽  
Electron Multiplier ◽  
Activation Condition ◽  
Activation Conditions

The Cu-Be alloys are widely used as the electron multiplier dynodes after the adequate activation process. But the structures and compositions of the elements on the activated surfaces were not studied clearly. The Cu-Be alloys are heated in the oxygen atmosphere in the usual activation techniques. The activation conditions, e.g. temperature and O2 pressure, affect strongly the secondary electron yield and life time of dynodes.In the present paper, the activated Cu-Be dynode surfaces at each condition are investigated with Scanning Auger Microanalyzer (SAM) (primary beam diameter: 3μmϕ) and SEM. The commercial Cu-Be(2%) alloys were polished with Cr2O3 powder, rinsed in the distilled water and set in the vacuum furnance.Two typical activation condition, i.e. activation temperature 730°C and 810°C in 5x10-3 Torr O2 pressure were chosen since the formation mechanism of the BeO film on the Cu-Be alloys was guessed to be very different at each temperature from the results of the secondary electron emission measurements.

Negative Life Events Associated With Deliberate Self-Harm in an African Population in Uganda

Crisis ◽  
2005 ◽  
Vol 26 (1) ◽  
pp. 4-11 ◽  
Author(s):  
E. Kinyanda ◽  
H. Hjelmeland ◽  
S. Musisi
Keyword(s):  
Life Events ◽  
Negative Life Events ◽  
Life Time ◽  
Later Life ◽  
Dose Effect ◽  
Deliberate Self Harm ◽  
Time Period ◽  
Significant Difference ◽  
Self Harm ◽  
Suicide Interventions

Abstract. Negative life events associated with deliberate self-harm (DSH) were investigated in an African context in Uganda. Patients admitted at three general hospitals in Kampala, Uganda were interviewed using a Luganda version (predominant language in the study area) of the European Parasuicide Study Interview Schedule I. The results of the life events and histories module are reported in this paper. The categories of negative life events in childhood that were significantly associated with DSH included those related to parents, significant others, personal events, and the total negative life events load in childhood. For the later-life time period, the negative life events load in the partner category and the total negative life events in this time period were associated with DSH. In the last-year time period, the negative life events load related to personal events and the total number of negative life events in this time period were associated with DSH. A statistically significant difference between the cases and controls for the total number of negative life events reported over the entire lifetime of the respondents was also observed, which suggests a dose effect of negative life events on DSH. Gender differences were also observed among the cases. In conclusion, life events appear to be an important factor in DSH in this cultural environment. The implication of these results for treatment and the future development of suicide interventions in this country are discussed.

Inactivation of Factor XIa in Vivo: Studies in Chimpanzees and in Humans

1996 ◽  
Vol 76 (04) ◽  
pp. 549-555 ◽  
Author(s):  
Walter A Wuillemin ◽  
C Erik Hack ◽  
Wim K Bleeker ◽  
Bart J Biemond ◽  
Marcel Levi ◽  
...  
Keyword(s):  
Antithrombin Iii ◽  
Life Time ◽  
In Vivo Studies ◽  
Clinical Samples ◽  
Plasma Samples ◽  
C1 Inhibitor ◽  
Elimination Kinetics ◽  
Factor Xia ◽  
Best Parameter

SummaryC1-inhibitor (C1Inh), antithrombin III (ATIII), α1-antitrypsin (a1AT), and α2-antiplasmin (a2AP) are known inhibitors of factor XIa (FXIa). However, their precise contribution to FXIa inactivation in vivo is not known. We investigated FXIa inactivation in chimpanzees and assessed the contribution of these inhibitors to FXIa inactivation in patients with presumed FXI activation.Chimpanzees were infused with FXIa and the various FXIa-FXIa inhibitor complexes formed were measured. Most of FXIa was complexed to C1Inh (68%), followed by a2AP (13%), a1AT (10%), and ATIII (9%). Analysis of the plasma elimination kinetics revealed a half-life time of clearance (t1/2) for the FXIa-FXIa inhibitor complexes of 95 to 104 min, except for FXIa-a1AT, which had a t1/2 of 349 min. Due to this long t1/2, FXIa-a1AT complexes were predicted to show the highest levels in plasma samples from patients with activation of FXI. This was indeed shown in patients with disseminated intravascular coagulation, recent myocardial infarction or unstable angina pectoris. We conclude from this study that in vivo C1Inh is the predominant inhibitor of FXIa, but that FXIa-a1 AT complexes due to their relatively long t1/2 may be the best parameter to assess FXI activation in clinical samples.

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