The Effect of Preheating and Non-Preheating in Cast Iron Welding Toward Mechanical Properties

Cast iron material is a material that has brittle properties and is less able to withstand stress due to the welding cycle caused by flake graphite in cast iron. Because of these problems, in connecting cast iron materials using the SMAW welding method, it is necessary to have heat treatment (preheating) to avoid the welding problems on the properties of cast iron. The purpose of this study is to determine the effect of heating and non-heating on the cast iron before the welding process. Therefore, this research will play a crucial contribution as a reference for cast iron welding researchers and cast iron welding process. The method of the research was experimental research, where the measurement results were obtained directly from the specimens. The welding was using an open V seam. The specimen used was cast iron with a thickness of 8 mm. One cast iron was given heat treatment at a temperature of 260ºC and the others did not receive heat treatment before being welded. The welding process used SMAW with CIN - 2 electrodes with a diameter of 3 mm. The test used the bending test on the face specimens according to the American Welding Society D1.1 standard. The results showed that there was an effect of the preheating treatment on cast iron, which that the non-preheating specimens were easier to fracture than the preheating specimens. Thus, it can be concluded that welding with preheating is better than welding without preheating.

Pengaruh Suhu Penyimpanan Elektroda Low Hydrogen E7016 terhadap Hasil Uji Tekuk Sambungan Las Pelat Baja Karbon SS400

Pengelasan merupakan proses penyambungan logam dengan menggunakan bahan tambah berupa elektroda. Sebelum melakukan pengelasan salah satu faktor penting yaitu perlakuan elektroda. Hal tersebut penting dilakukan terutama pada perlakuan penyimpanan elektroda tipe <em>basic low hydrogen</em> (E7016). Penelitian sebelumnya menunjukkan bahwa pemanasan elektroda dapat menghindari retak sambungan las pada uji <em>face bend</em>. Tujuan penelitian ini yaitu untuk mengungkapkan pengaruh perlakuan suhu penyimpanan elektroda terhadap uji tekuk sambungan las. Metode dalam penelitian ini menggunakan penelitian eksperimen, dimana penelitian dilakukan dengan memberi perlakuan pada suhu penyimpanan elektroda. Elektroda diberi perlakuan suhu penyimpanan dengan variasi 40° C, 80° C, dan 120° C selama 30 menit. Elektroda yang digunakan yaitu jenis <em>low hydrogen</em> (E7016) dan material sampel menggunakan pelat SS400. Sambungan las menggunakan kampuh V tunggal dan pengelasan sampel menggunakan proses <em>shield metal arc welding</em>. Pengujian tekuk spesimen dilakukan sesuai standar American Welding Society D1.1. Hasil penelitian menunjukkan bahwa semakin tinggi suhu penyimpanan akan menghasilkan daya tahan retak yang baik pada uji <em>face bend </em>dibandingkan dengan hasil pengujian <em>root bend</em>.

The Design Provisions of the New AWS Structural Welding Code – Titanium

The American Welding Society has developed its first welding design code for titanium alloy welded structures, through its consensus standards process and the work of many volunteers,. Defining the provisions of this new code required collecting and summarizing both strength and fatigue data for titanium structural welds. The design provisions were based on these data, but only in context of other provisions of the code in areas of welding procedure qualification, fabrication, and inspection. For instance, the allowable imperfection sizes found on inspection had to be correlated with the expected fatigue performance of imperfect welds. Test data from welds in the primary structural alloy Ti-6Al-4V are described for several weld configurations, both with and without welding imperfections.

Development of Machine Element OEM and Repair Specifications

MIL-STD-1687 (SH) has been in use for many years as one of the specifications that the United States Military performs thermal spray operations at overhaul facilities. The U.S. NAVY has asked AWS (American Welding Society) to develop an ANSI/AWS national standard to replace it and then provide long range maintenance of the new specification when necessary. This paper discusses both the procedure used to develop this standard and the content of the specification. Particular attention will be paid to the quality controls, training of operators and use of other specifications to accomplish compliance with this specification. The approval process for this document will be discussed with a probable time line including a plan to publicize and smoothly replace the MIL-STD-1687 (SH) specification. The further integration and use of it globally will be discussed and recommendations presented. The new standard will be in harmony with the ISO thermal spray standards program.