Plate lamination defect is one of the primary processing discontinuity that originates during hot or cold forming processes and is considered as a serious metal plate defect. All the metals contain discontinuities at micro and macro levels. These discontinuities, when above the acceptance level, are termed as defects. The discontinuities in metal are classified according to the stage of manufacturing in which they initiate. Plate lamination defect can be defined as flat and thin subsurface separations present inside metal plate, parallel to the surface of the plates. The sources of this defect are inherent discontinuities present in metal such as inclusion and porosity, which are flattened during the rolling process. Carbon Steel Plate Lamination Defect & ReasonsA carbon steel plate is produced by the process of hot or cold rolling a thick slab. During this process, carbon steel may pass through the rollers many times to achieve the desired thickness.Each pass results in an increa…
Comparison of the use of rutile and cellulosic electrodes
Types of electrodes and their compositions
Many types of manual metal arc (MMA) electrodes are available on the market. Depending on the main constituent of their flux, they are grouped into three categories: cellulosic, rutile and basic. All electrodes consist of a cored wire (typically 2.5–6mm diameter) coated by a flux. The core wire is generally made of low-quality riming steel and the fluxes contain many elements allowing refinement of the weld macrostructure.
The composition of the flux impacts the electrodes’ behaviour. The main constituents of the different types of electrodes and the shielding gas created for each are described in Table 1 (Bowniszewski, 1979). Table 1 Main constituent of the three possible types of electrodes and shielding gas created by its combustion. Electrode typeMain constituentShielding gas createdRutileTitania (TiO2)Mainly CO2BasicCalcium compoundsMainly CO2CellulosicCelluloseHydrogen + CO2
Immediate Requirement for Multi Discipline NDT Technicians
Exp: 5 - 10 yrs.| Opening(s): 30
Review the job packs and understand theNDT requirements specified. - Keep all stationary Equipment instruments/ Tools in good and calibrated condition. - Coordinate with NDT coordinator and the stationary equipment Inspector for carrying out NDTactivities. - Prepare detailed reports and submit to the coordinator.
Desired Candidate Profile
- Minimum work experience of five (05) years in multi discipline NDT in a Petrochemical, Oil & Gas plant. - Work experience of turnaround inspections of Columns, Vessels, Exchangers, Tanks, Piping etc. - Experience in reading and understanding procedures, specifications, codes and standards related to NDE and area of work. - Experience in writing, reporting and record keeping the detailed technical reports related to NDE. - Working experience in Shutdown and turnaround will be preferred. - Typical plant experience will be an added advantage. - Good …