haiii i am ramu.please tell me conclusion for flaw tracer project

Abstract

Penetrant tracer processes are employed for the purpose of detecting various kinds and sizes of surface flaws or defects in machine parts, ceramics, Welded joints, and the like. The processes involve immersing the part to be tested in a penetrant liquid containing a dissolved dyestuff which imparts either a visible color or a fluorescent color or characteristic to the liquid. The penetrant liquid enters any surface flaws which are present, and after the part is cleaned by a suitable solvent, emulsifier or washing step, entrapments of the dyed penetrant liquids remaining in surface flaws can be seen by appropriate inspection methods, thus revealing the location and in many cases the character, shape, and width of the flaws.

In cases where a flaw is relatively large, a relatively large amount of tracer may become trapped in the flaw, and resulting tracer indications may be observed easily.v However, where a flaw is quite small, the tracer indication is less easily seen, and in some cases may not be visible at all.

It has been found that all dye penetrant flaw tracers exhibit a property of dimensional sensitivity whereby there exists a critical thickness of a film of the tracer liquid below which a fluorescence or color response cannot be seen. In addition, it is possible to accurately control the so-called dimensional sensitivity of liquid tracer materials, and I have described and claimed methods and means to this end in an abandoned copending application, Serial No. 149,061, filed October 31, 1961, a continuation-in-part of my application Serial No. 82,374, filed January 13, 1961, now abandoned.

Inasmuch as the ability of a flaw tracer dye penetrant material to reveal the presence of small flaws in the surface of a part may vary over a wide range of dimensional sensitivities, it often becomes necessary to evaluate the flaw detection efliciency or performance of the penetrant so as to be sure that it is functioning properly. For this purpose, a standardized and reproducible testing device is essential so that simulated flaws may be obtained which lie in a range of sizes likely to be encountered in practical flaw inspection processes and procedures.

In a manner similar tothe penetrant method for detecting surface cracks or flaws, a fluorescent solder flux tracer method may be used to detect soldering defects, such as porosities, cold solder joints, soldering flux residues, and the like, so it is desirable that a testing device for the evaluation of liquid tracer flaw detection efficiency should be adaptable for convenient use on a wide variety of liquid tracer types, including the important penetrant and solder flux tracer materials.

The principal object of the invention, therefore, is to facilitate the testing or evaluation of performance of liquid penetrant tracer materials.

Another object of the invention is to provide an im proved testing method which will simulate typical surface flaws over a range of useful dimensions.

A further object of the invention is to provide an inexpensive device which may be re-used repeatedly to give reliable and reproducible flaw indications in the evaluation of various dye penetrant or dye solder flux tracer materials.

Penetrant tracer processes are employed for the purpose of detecting various kinds and sizes of surface flaws or defects in machine parts, ceramics, Welded joints, and the like. The processes involve immersing the part to be tested in a penetrant liquid containing a dissolved dyestuff which imparts either a visible color or a fluorescent color or characteristic to the liquid. The penetrant liquid enters any surface flaws which are present, and after the part is cleaned by a suitable solvent, emulsifier or washing step, entrapments of the dyed penetrant liquids remaining in surface flaws can be seen by appropriate inspection methods, thus revealing the location and in many cases the character, shape, and width of the flaws.

In cases where a flaw is relatively large, a relatively large amount of tracer may become trapped in the flaw, and resulting tracer indications may be observed easily.v However, where a flaw is quite small, the tracer indication is less easily seen, and in some cases may not be visible at all.

It has been found that all dye penetrant flaw tracers exhibit a property of dimensional sensitivity whereby there exists a critical thickness of a film of the tracer liquid below which a fluorescence or color response cannot be seen. In addition, it is possible to accurately control the so-called dimensional sensitivity of liquid tracer materials, and I have described and claimed methods and means to this end in an abandoned copending application, Serial No. 149,061, filed October 31, 1961, a continuation-in-part of my application Serial No. 82,374, filed January 13, 1961, now abandoned.

Inasmuch as the ability of a flaw tracer dye penetrant material to reveal the presence of small flaws in the surface of a part may vary over a wide range of dimensional sensitivities, it often becomes necessary to evaluate the flaw detection efliciency or performance of the penetrant so as to be sure that it is functioning properly. For this purpose, a standardized and reproducible testing device is essential so that simulated flaws may be obtained which lie in a range of sizes likely to be encountered in practical flaw inspection processes and procedures.

In a manner similar tothe penetrant method for detecting surface cracks or flaws, a fluorescent solder flux tracer method may be used to detect soldering defects, such as porosities, cold solder joints, soldering flux residues, and the like, so it is desirable that a testing device for the evaluation of liquid tracer flaw detection efficiency should be adaptable for convenient use on a wide variety of liquid tracer types, including the important penetrant and solder flux tracer materials.