Penetrant Testing Blog

Qualification Documents

Time Flying and Some Perspective on Qualification Documents It is an interesting question – Is penetrant inspection a new technology or an old one? For newcomers, it probably is old. But some old timers can still remember the early days when it was an interesting and promising new inspection method. Thinking about this made us decide to present a bit of history...

Blueline NDT, Queries

A New Idea Those who were at the Fall ASNT Conference and attended the Penetrant technical talks heard a presentation by Charles Mazel, of Blueline NDT. His talk discussed some new ideas about working with fluorescent magnetic particle inspection and fluorescent penetrant inspection. We all know how these inspections work. In order to see any indications of flaws, we go into a...

AMS 2647, Audits, Developer Studies

AMS 2647 Committee K work has continued on revisions toAMS 2647 via convenient and fairly frequent telephone conferences. The last such conference was held on January 17, and it was the usual two hour meeting. Since this specification is mostly a user specification, there were only a few inputs from Met-L-Chek®. However, we assisted in correcting wording that referred to penetrants as...

Responses: History of the Specification for Qualification of Penetrants, Singapore Air Show 2016

It is always interesting to see what issues of “The Penetrant Professor” stirs response from the readers. The January 2016 issue, which dealt with the history of the specification for qualification of penetrants prompted numerous emails from readers. From a retiring government practitioner,“ Lisa, I will be leaving this office next week, please discontinue the Pen Prof; it’s been a great publication.” From...

Requirements of UV-A Lamps, ASTM E-07 Committee, ASTM E-3022, RRES-90061

“Stuff You Need to Know” John Brausch, of the U. S. Air Force, has released a draft of suggested requirements for the approval of UV-A lamps to be used in NDT inspection. The draft addresses several key points regarding the UV-A sources, each of which is important for reliable inspection. Important points are as follows: The wave length of the emitted UV-A...

False Representations of Met-L-Chek … ¿USED CAR SALESMEN?

¿USED CAR SALESMEN? We have all heard the story of the used car salesman who alleged that the wreck that he was selling had belonged to “a little old lady from Pasadena” who only drove it on Sundays to go to church. Well, salesmen and saleswomen sometimes use rhetoric like this to convince a person to buy. And, as it turns out,...

Penetrant Sensitivity, Nomenclature, Checking Materials

Nomenclature This describes a recent mix-up due to a misunderstanding about how some NDT products are described. We all know that penetrant products are clearly described by what they do. We know what penetrants are, what removers are, and what developers are. But when these products are shipped, they need to be classified by nomenclature listed in the NMFC (National Motor Freight...

Star Burst Panels or “those damn tam panels”

At the Fall meeting of ASNT in Charleston, South Carolina, George Hopman presented a talk in which he described tests that he had made to determine if the use of star burst crack panels, widely known as TAM panels or PSM panels, were able to determine if a penetrant system was “out of spec”. Ever since the TAM panel was designed at...

How small of an opening will liquid penetrant fill? SEM of crack indication with penetrant.

The Penetrant Professor has always tried to give answers, to the many questions that come to Met-LChek, based on years of hands on experience, and scientific experiments. Without a doubt the most frequently asked question is,” How small a crack will penetrant find?” This is a great question because it challenges the volumes of NDT text books and study guides viewed as...

Water Content

ASTM E-1417 requires that the water content of in-use water washable penetrants and lipophilic emulsifiers be less than 5 percent. The listed analytical methods for measuring this percentage are ASTM D-95 and a modified Karl Fischer method described in ASTM E-1417 Annex 1. We recently received an inquiry as to whether the standard Karl Fischer method is also an acceptable alternative to...

Mixing Batches and Re-filling a Penetrant Tank

We do not know to what extent this subject is a problem for anyone in the USA, but it seems to have come up in Europe. There is a lot of common sense involved in this subject, and probably most, if not all, of our readers will agree with that. But let us take a look at the subject. The easiest situation...

Recap: ASTM & NDTMA 2017, ASTM E165 (cleaning, elemental analysis), ASTM E709 (parallel magnetism), ASTM E-1316

ASTM & NDTMA 2017 Meeting, ASTM E165 (cleaning, elemental analysis), ASTM E709 (parallel magnetism), ASTM E-1316 As usual, the January meeting of ASTM Committee E-07 was held in Plantation Florida on January 23 and 24. The penetrant section of the meeting dealt with revisions and updating of E-165, a subject that the committee has been working on for several meetings. The ASTM...

Penetrant Tank Contamination

Here again, there is a lot of common sense involved. One should simply see that junk- oops, foreign material – does not get into the penetrant. But it does happen. There is the obvious poor practice of people throwing stuff into the tank. We are told that tanks have been seen with plastic water bottles floating in them, and we know of...

Both ASTM E165 and E1210 test methods reference immersion post rinsing for PE hydrophilic. Practice E1417 does not.

INTERESTING QUESTION: We have had this question several times in the recent past and thought we would share the question and the answer, we uncovered, to help others who are struggling with the same issue. A recently received email asked the Prof. the following; “Both ASTM E165 and E1210 test methods reference immersion post rinsing for PE hydrophilic. Practice E1417 does not,...

Electrostatic Developer Application, Questions for the Penetrant Professor

Electrostatic Developer Application We suggested, in the last issue, that we would discuss some of the results of the CASR work on developer application, and, in particular the recent work on electrostatic application. At the Fall ASNT meeting in Las Vegas, a technical paper on this method was presented, and this was followed up by a telephone conference on December 12 to...

Emulsifier Make-Up and Dilution

There is a bit of turmoil concerning hydrophilic emulsifiers that we had tried to address by providing a concentration chart in our literature, and subsequently we added this to the labels on the containers. But, then there were claims that this might not be applicable to all batches. So, then we switched to providing a custom graph for each batch, so that...

Can you add an additive to a penetrant?

Another faithful reader and customer asked if there was an additive that could be used to facilitate the electrostatic spraying of penetrant. While the question was innocently made, the person either forget or did not understand that the penetrant in use was a QPL approved material under AMS-2644. As such, its composition is frozen and may not be changed without renaming the...

Does using aged penetrant materials reduce the likelihood of detecting fatigue cracks?

There is a body of research going on at a couple of places that have to do with penetrant inspection. At Sandia laboratories, the following question was investigated: “If a field inspector accidentally used aged penetrant materials, would that reduce the likelihood of detecting fatigue cracks?” To investigate this question, a careful laboratory test was designed, using specimens containing low cycle fatigue...

Aerosol Spraying and Spraying Technology

AEROSOL SPRAYING Almost every inspector understands that in order to get good penetrant indications, it is necessary to apply a thin coating of developer. This is particularly true when the inspector uses form “d” nonaqueous aerosol developer. We often get questions about other methods of applying form “d” developer, for example, using pump spray bottles, paint sprayers, etc. While all of these...

When performing multiple types of PT inspections on the same part, is it preferable or recommended to performing them in any particular order?

One would think that as simple in concept that penetrant inspection is, the number of questions that could be posted would be finite. That may be true, but finite is just a number that does not reach infinity, as we are finding, after half a century of answering questions. There seems to always be something different that folks want to know about....

Penetrant History: Loy Sockman, Glass Standard, Sandblasted Panel, Thermally Cracked Block, Panels

In October 2015 Bill Mooz, President of Met-L-Chek, gave a talk at the Fall ASNT Conference in Salt Lake City, Utah. Bill has been closely involved with the development of the specifications govern- ing penetrant inspection materials, and used his decades of experience to present a paper on the historical development of the specifications for the qualification of penetrants. We offer a...