(a) assessment of porosity, inclusions and other defects
According to the thickness of the test site to determine the size of the assessment frame, with the assessment frame to select the most serious defects in the detection area, the size of the defect, the different sizes of defects into different points, and then according to the number of points to assess the grade.
(ii) Assessment of shrinkage and shrinkage defects
Strips of shrinkage measured its maximum length, dendritic, feathery, spongy shrinkage measured its area, and then according to different thicknesses of different levels of the maximum amount allowed to assess the grade.
(c) Cracks (hot cracks, cold cracks) and cold partitions are all impermissible defects.
(d) the negative assessment steps first qualitative, then quantitative, and finally graded.
For the type of defects in the valve body cast steel parts and the characteristics of the valve body structure, the use of radiation detection technology. According to the oxygen valve and cryogenic valve body non-destructive testing technology requirements specified in the relevant standards, strict valve quality to ensure the safety and reliability of oxygen valves and cryogenic valves, and thus ensure the safe operation of the whole life of small air separation units, large air separation units and liquid air separation plants long cycle.
Dear Air Separation's valve housing castings are flexibly inspected using advanced technology in small air separation units, large air separation units and liquid air separation plants.