Dye penetration test

The amount of solvent that can be taken into a vessel for dye-penetrant testing or other purposes should be limited so that evaporation of the complete amount will not bring the concentration above the safe concentration, for example, the threshold limit value, making allowance for the air flow if the vessel is force-ventilated. 

Dye penetrant test on the welded surfaces for any blowholes should be conducted before the equipment, pipes and fittings are subjected to hydraulic testing. 

Tables 35.2 and 35.3 depict the effect of coating thickness on the dye penetration tests for coatings prepared at 2.6GJ/kg and 21.8GJ/kg, respectively. Holding a...

Figure 35.5 The range of coating thickness that satisfy both frictional coefficient and the dye penetration test at WjFM 2.6GJ/kg.

Figure 35.7 Pictorial view of coated and dye penetration tested tube, top and bottom part of the whole tube that didn t reach the plasma zone is stained, but no stain occurred in the coated section of the tube.

The retardation of the migration of silicone oligomers from the silicone tubing after being coated indicates that the plasma polymer coating applied to the tube substrate is in a form of continuous film with barrier characteristics instead of some other physical forms (e.g., powder). Direct evidence of this aspect can also be seen from the fact that all test specimens prepared had passed the dye penetration test. 

The traditional approach to evaluating the integrity of ampoules has been through 100% inspection by a vacuum dye penetration test. The basic procedure for the vacuum dye penetration test is to place racks of sealed ampoules in a dye bath, apply a vacuum for a period of time, remove and rinse the ampoules, and then inspect for dye penetration. 

If it is to be considered that microorganisms can penetrate capillaries with diameters as small as 0.4 pm (and this is a reasonable assumption, because Pseudomonas diminuta was first icountered from having passed through filter membranes with 0.45 pm pone size ratings), Poiseuille s law can be used to calculate the dimensions of a satisfactory vacuum dye penetration test. 

Given ampoules with wall thicknesses of 4 x 10 cm, methy lene blue with a viscosity of 10 poise in 1% solution, and a pressure differential of 2 x 10 dyn/cm, the minimum time required for 10 mL (a reasonable guess at the minimum perceptible volume) to penetrate through a 0.4 pm pinhole would be 9 h. Practical testing times in the vacuum dye penetration test are in the region of 15 min. 

If package cracks are suspected, a dye penetrant test should be performed. In this test, a fluorescent dye is applied to the package surface and then wiped clean. Examination of the part under UV-light reveals residual dye in package cracks. This test is applicable both to hermetic parts and plastic-encapsulated microcircuits (PEMs). 

A test to determine the characteristics or properties of a material or substance that does not involve its destruction or deterioration (e.g., x-ray examination, ultra-high frequency sound, etc.). See also Dye-Penetrant Testing. 

Radiography test and dye penetration test— for welded joints... 

Conventional dye penetrant testing for surface crack detection in PMC is described in older literature (45), but is now rarely used, except for highlighting cracks in PMC after destructive sectioning (46). 

C949 specifies a dye penetration test. Poroton. Insulating bricks in which foamed polystyrene beads are mixed with the clay as a combustible component, leaving a porous structure. 

Cracks have been discovered in cast primary pump bodies, valves and elbows in main circulation loops. Dye penetrant testing revealed a number of cracks. The cracks were found both on the inside and on the outside of the casings. Moreover, the duplex austenitic-ferritic structure of cast steel pipes used in some NPPs is a potential cause of an embrittlement due to the thermal ageing effect on the ferritic part. It is difficult to perform reliable volumetric non-destructive testing by ultrasonic techniques of the cast material. 

The BWR pilot plant life extension study [6.31, 6.32] recommended that at least one jet pump inlet mixer subassembly should be disassembled, dye penetrant tested, and examined for erosion effects following 30 to 40 years of operation. The stainless steel material of the jet pump together with favorable inspection results to date indicates that... 

The significant factor for having low perforation energy was also identified from postindentation dye penetration tests (Figure 19.12). The dye penetration tests revealed minimum delamination around the hole and an extended narrow cross-pattern in the cases of pristine and 5 wt% GB-modified laminates. On the other hand, 1 and 3 wt% GB laminates showed excessive delamination. This implies that the energy absorption mechanisms in 1 and 3 wt% GB laminates were not only due to deformation but also to mainly interlaminar delamination. 

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