Demagnetize prior to weld

Knowledge for Reference: Demagnetization: Magnetic field strength above a critical intensity is affecting the weld-ability. Well-known interference are: – Arc welding procedures are sensible to high magnetic field strengths. Welding in presence of magnetic fields may cause magnetic arc blow. Arc blowing is strongly reduced below field strengths of 16 A/cm (=20 Gauss). – In arc welding with filler wires (FCAW/GMAW/SMAW) , sticking of the wire to a side is caused when significant magnetic fields are present. The sticking is minimized below field strengths of 8 A/cm (=10 Gauss). – In electron beam welding (EBW), the quality of the welding is strongly affected by magnetism. At field strengths well below 2 A/cm (=2.5 Gauss) the disturbing influence on welding … Continue reading Demagnetize prior to weld

Questions and Answers for Marine Engineers

Explain the term water hammer indicating possible effects on the system ? Water hammer occurs when steam is admitted into a cold pipeline. The steam condenses producing both water, and a vacuum (when the water seals the pipeline from the steam supply). This vacuum causes the water plug to be drawn into the closed end of the pipe with increasing velocity producing high impact forces on the pipework. This impact force can be high enough to rupture the pipeline. State how the risk of water hammer may be avoided ? Water hammer is avoided by slowly admitting the steam into the cold line, and draining/venting … Continue reading Questions and Answers for Marine Engineers

List of queries

RBI/HAZOP/HAZID. Risk assessment Testing follow guide rule. Metallurgy. WPS sample. Offshore book, corrosion book, pipeline book. Piping stress, free span. Engine problems. buttering qualify or not??? nozzle of boiler tube sheet require qualify WPS QW 288 Skew Tee joint Cu-Ni procedure WELDING REPAIR (ASME 31.3 NACE) CVN B31.3 EXEMPTION UNDERSTANDING Ship Hull Inspection PROJECT CONTROL: ITP MASTER SCHEDULE (DETAIL AND NOTE ON SYSTEM) BEFORE LAUNCHING BEFORE SEA TRIAL DELIVERY DOCUMENTATION   Continue reading List of queries