Investigative Experience

24 Years of Experience Means Receiving More Than Just A Basic Spreadsheet Of Wall Thickness Measurements

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The use of ultrasonic technology to provide an assessment to the condition of piping systems is widely employed around the world, and in multiple fields.  Quality of work runs from very good in some examples, to abominably poor in others.  Contracting to have ultrasonic testing performed at a piping system often results in a primitive spreadsheet of wall thickness measurements and nothing more.

Handwritten measurements on a formatted page are not even that uncommon – as we have documented elsewhere on this Internet site.  The below left side hand drawing is not a 5th grader’s homework assignment on fractions, but one of nine similar pages of a final report submission defining the condition of a 24/7 cooling tower loop to an ultra critical government data center.  And no – adding a zero to a two decimal place wall thickness measurement does not increase its accuracy to three decimal places, as one level III UT technician and the company’s senior data analyst adamantly argued.

A final report from most UT testing services is typically 2 to 6 thickness measurements taken at a few test locations and the original pipe wall thickness – leaving the client the remaining and more critical task of determining what it all means.

Virtually all ultrasonic testing reports we have seen have been nothing more than a spreadsheet presentation of raw data, rather than a true “piping inspection, “ “pipe condition assessment,” or “fitness for service evaluation” as the client likely anticipated and was undoubtedly led to believe.  For surprisingly many reports which have been submitted to us for review, comment, and interpretation, measured wall thickness values are obviously wrong, or not even within the realm of possibility – thereby introducing error on the part of the UT technician as another issue.  We have even reviewed reports where certain information has been falsified, where the ASTM published wall thickness specifications have been stated incorrectly, or where there has been a complete misinterpretation of the ASTM code resulting in a totally worthless assessment.

Recipients of such reports, after submitting their raw data to us in the hope of our being able to unravel its meaning, are often disappointed to find their report has little to no value.  The combination of limited field data, poor documentation, inaccurate measurements, contradictory results, and zero explanation to its meaning leaves most property managers and engineers back at their original starting point – only now many months after the failure event prompting the investigation.

As one property manager jokingly stated to us in his introductory phone call, “This piping integrity report I have in front of me is great.  It tells me there is pipe in my building.”

Far Greater Benefit Possible

CorrView International, LLC offers a significantly higher level of service due to our 24 years performing UT testing, our 35 plus years of experience in multiple fields related to piping systems, and due to the ability to apply our expertise from multiple fields in the pursuit of the answers to your questions.  By combining ultrasonic testing with knowledge from many different disciplines, we provide not only the wall thickness analysis which was the primary focus, but a much more intensive and far more detailed explanation and understanding of that wall thickness data relative to the property involved.

The various areas of expertise we incorporate into every ultrasonic pipe testing investigation are:

Ultrasonic Equipment & Technology

We employ the latest ultrasonic testing instruments by Panametrics / Olympus and utilize their advanced features to their maximum potential.  Having waveform displays, only certified accurate measurements are recorded.  We will not create  chaos to a critical data center by measuring and reporting the 0.021 in. paint thickness for its 24 in. condenser water main as its actual wall thickness, and then warning that just writing the thickness dimension on the pipe could cause its failure.

All wall thickness measurements are electronically data logged rather than written down by hand; eliminating human error and making future retreival and confirmation to a questionable measurement possible by being able to review each original wall thickness waveform.  The Panametrics echo-to-echo feature eliminates the need to remove surface paint – thereby speeding our progress, and eliminating measurement error due to grinding as well as the client’s need for re-painting.

We only employ highest frequency dual element probes in order to identify deepest pitting detail.  Experienced UT technicians guarantee that the wall thickness measurements cited are accurate and precise to the highest degree possible.

Following our five pages of very strict field testing and reporting procedures further ensures results that can trusted and relied upon.

Corrosion Controls & Limitations

Having began in the chemical water treatment industry in 1981, we have a fundamental understanding of those negative forces constantly at work to destroy a building’s critical piping infrastructure, as well as the tools capable of preventing it.  Each type of corrosion poses a different threat; often combining to produce even more severe deterioration under certain circumstances.  For instance, the impact of galvanic interaction and high corrosion activity is typically far greater than both threats separately.

Knowledge of the chemical water treatment industry provides an immediate understanding to the corrosion problems which may exist – either due to lacking chemical protection, a design error, or to inherent vulnerabilities of the piping system.

Interpreting measured wall thickness data requires an understanding of the forces which produced such losses in the first place.  Recognizing the many limititations of water treatment to prevent every form of corrosion at increasingly more complicated piping configurations is equally important.

Different Piping Systems

Every piping system has its own inherent corrosion characteristics in terms of high to low variation, degree of pitting, forms of corrosion, failure mode, and potential threat.  Dry fire pipe corrosion differs from condenser water corrosion, which differs from steam condensate corrosion, which differs from galvanized steel corrosion.  Corrosion activity will also vary within certain piping systems, such as dry fire sprinkler, to produce widely varying wall thickness measurements which may seem conflicting unless evaluated in the proper context.

Knowing what wall loss is normal or high, where corrosion problems should be expected, and where they should never occur is very much related to the piping system itself, and can greatly influence the direction of the field testing as well as the final interpretation of the test data.

With all piping investigations limited to some extent due to piping accessibility, time, and cost, understanding the most likely areas to show a potential weakness is paramount.

Pipe Corrosion Characteristics

An ultrasonic testing investigation to any commercial building property can only address limited areas of the piping system and cannot possibly address every square inch of all its pipe.  Physical access is one limiting issue and cost the other – thereby resulting in an assessment based upon far less than 1/10th of 1 percent of the entire piping system.

Understanding the corrosion characteristics of different piping systems, therefore, is critical to choosing the appropriate test locations.  Investigation immediately prior to an upward elbow, appropriate to condenser water and steam service, would be irrelevant to a domestic cold water or wet fire sprinkler line.  By-pass / tempering lines for condenser water systems contain significantly greater threat than a by-pass / tempering line around a domestic hot water heater.

Often, testing is performed at the easiest and most accessible locations, or in the wrong locations entirely.  Misconceptions abound by building engineers, water treatment professionals, and even UT investigators to where corrosion activity is most likely.  Combined with limited data, gained from the wrong locations and often inaccurate in the first place, many ultrasonic investigations do more damage than good.

Building Function & Operations

The function and purpose of a building property determines the design and layout of its piping systems. Computer data centers run piping differently than a high rise office building or manufacturing plant.  Older properties from the 1950’s are designed and constructed quite differently than today’s modern structures – in terms of piping layout, system complexity, installation, as well as in the thickness and quality of materials used.

Varying levels of importance also exist.  Corrosion at a fire sprinkler system for a nursing home, and where a build-up of rust product can totally stop the flow of water to the sprinkler heads, is far more critical to its residents than its cooling tower air conditioning loop.  A pinhole leak at the roof level condenser water pipe of a data center, while of critical concern, still does not rate the level of threat of a total thread separation leak occurring below its server room floor.

Measuring wall thickness is often the easiest aspect of any fitness for service piping evaluation.  Interpreting those measurements into an accurate corrosion rate estimate, and then assessing its future impact based upon its function and location is often of far greater importance rarely attempted by most testing services.

Piping System Engineering

Changes in the way piping systems are designed and physically installed has had a pronounced impact in creating new corrosion problems never before encountered.  Unfortunately, these relatively new threats remain unrecognized within the building and design engineering industry and therefore continue to propagate.

Fully reduntant and infinitely configurable cooling systems, and the interest toward unlimited future expansion, have built into such systems new dead zone areas for aggressive under deposit corrosion to thrive.  Recommendations by “data center industry experts” to weld galvanized steel dry fire sprinkler pipe together above server room computers for greater reliability actually creates an advanced pitting condition and quicker failure due to the internal zinc protective being burned away.

Running 1 in. by-pass lines between 24 in. headers with the belief that it will prevent debris from settling at its dead ends is an utterly worthless effort.  Adding multiple threaded and valved off futures to piping risers, a decade or more before they will ever be used, guarantees their failure prior to ever seeing service.

Thinner grade pipe of lower quality and far greater corrosion susceptibility is common.  Frequently supplied from foreign sources which are well known and documented to manufacture sub-quality products, low quality and often defective pipe has become the common denominator to most severe piping failures.  Corrosion rates exceeding 10-15 MPY are no longer a rare event.

Politically driven green influences, whether using captured rain water as cooling tower make-up, non-chemical corrosion control devices, variable speed condenser water pumps, or less effective chemical corrosion control alternatives – all look great on paper and for publicity, but translate to higher pipe corrosion losses in the real world.

Piping Materials

Lower quality pipe having far greater vulnerability to corrosion is the primary issue impacting the building and construction industry today.  Typically ignored until a failure occurs, the use of cheap and low quality piping products has reduced the life expectancy of most piping systems to about 40% of what was previously provided.

Thin wall schedule 10 pipe is now the standard for fire sprinkler service, with schedule 7 and even schedule 5 pipe no longer uncommon.  ERW seamed pipe has also replaced seamless pipe in all but high pressure steam service applications.  The quality and corrosion resistance of steel and galvanized steel pipe, foreign and domestic, has plummeted.

Replacing steel condenser water pipe which lasted 58 years will likely result in a system reaching the end of its useful service in only 15 years or less.  Adding new steel pipe to an older system having a 3.5 MPY corrosion now often results in a wall loss of 12 MPY at the newer pipe.

Recent investigations producing results nothing less than frightening, make the poor quality foreign pipe from the 1980’s look good by comparison.  New condenser water systems failing in 6 years and less.  Galvanized steel domestic water lines in 3 years.  Ductile iron sanitary waste lines in 18 years.

Even worse, no one cares to the quality of the pipe they are installing.  Whether it is turning a blind eye to defective ERW pipe having a 50% incomplete seam, threading thin wall schedule 7 fire sprinkler lines, sweating Type K copper pipe having Type M dimensions, or even preparing pipe where the original Chinese stamp and logo is showing through its American counterfeit overlay – far too much defective pipe could have been caught and piping failure avoided by any one of dozens of industry professions handling it along the way.

Totally ignored as an issue until it is too late, the selection of piping materials has today become far more critical than ever before, but still rates far lower than the section of the lobby flooring.

Unfortunately, it is becomming nearly impossible to obtain good quality pipe capable of providing even a low fraction of the service life provided by pipe manufactured decades ago

Computers & Reporting

Knowledge of computers, programming, and the specific needs of our clients has allowed us to produce a report format offering the greatest amount of useful information, and at relatively low cost.

Each report is compartmentalized with different areas and levels of information. From an executive summary to a graphical overview, to the fine statistical results of each pipe section tested, and finally a detailed narrative explaining the entire report – our goal is to provide our client with an understanding of their piping system equal to our own.  Differing levels of information are also provided in order to satisfy everything from the limited interest of a senior manager, to the legal focus of a trial attorney, to the most finite and technical questions posed by a professional engineer in their critical review.

In what has evolved in over 25 years of providing this service, few if any questions are ever left remaining following the presentation of our ultrasonic test report.

Investigative Integrity

The importance of beginning an ultrasonic investigation properly and following a clearly defined procedure cannot be overstated.  With politics and conflicting interests frequently present after many corrosion induced issues, ignoring outside influences in the pursuit of the facts can be challenging.

Potential complications exist due to pre-existing opinions, a restriction or limitation of too few test locations, incorrect assumptions, inaccurate building and piping information, directed focus toward the wrong areas, interference by other corrosion authorities, the interest of responsible parties to shield their involvement in the problem, as well as other issues.

Documenting that a new $85,000 water filter, purchased in response to condenser tube fouling, is installed backwards will not be well received.  Nor does documenting that the last 4 years of 0.5 MPY corrosion coupon reports completely misrepresented a wall loss which was actually 9 MPY.  Any piping contractor will react with the expected aggression at being told that the dielectric fittings he installed throughout the building between the brass valve and copper run-out piping should have instead been installed between the carbon steel riser pipe and brass valve.

Any corrosion induced failure involving litigation always hightens the interest to direct or focus an investigation in solely one direction, and away from another.

In many situations, which are not always well received, we find it necessary to gently advise our clients to change the focus of their intended investigation to a direction more likely to define pipe condition, rather than prove someone’s often misguided point.   Althogh not immediately recognized as valid, our final report, and the answers provided, will often validate earlier advised changes in direction.

Excellence, Observation, and Curiosity

The power of observation is the second most important aspect to any ultrasonic investigation next to technical ability.  Excellence, which is significantly devoid in most disciplines today, means taking the interest and time to incorporate all pertinent information into the final report.

While most corrosion problems remaing entirely hidden, many reveal themselves – such as rust deposits in the cooling tower pan and strainers, or blue-green oxidation deposits at a brass valve.  Pipe of a slightly different shade of paint, and noticeably absent of any dust along its top, strongly suggests pipe replacement.  Differences in welding signature also points to pipe replacement.  New thread sealants, still soft, always suggests a recent failure event.  Stainless steel pipe nipples mean the failure of the original steel pipe nipples were quite dramatic to cause such a response.

Concrete block and cement of a different color suggests entry into the pipe chase behind it.  Two different pipe stamps on the same pipe section, or a faint appearance of a Chinese pipe stamp between the bolder lettering of an American manufacturer almost always means counterfeit pipe.  Identifying pipe having 20+ different foreign pipe stamps installed at one system means the contractor used anything he could find at rock bottom price.  It also suggests that other corners were also likely cut.

Such obvious signs of a problem are almost always overlooked during most due diligence and engineering surveys, with the weakness of the piping system eventually revealing itself only after it is too late.

Careful observation for physical clues during a piping investigation, and the curiosity to pursue an issue which just doesn’t seem to make sense, almost always produces a better understanding of current piping conditions and a more conclusive report.

Legal Requirements

Where litigation may be involved, a higher level of investigation and attention to precise detail is always required.  The anticipation of an opposing opinion to almost every aspect of the investigation is also critically important.  Alhough a one day error in stating the installation date of the pipe has absolutely no possible impact upon an assessment of corrosion rate activity and pipe condition, it does provide an opposing attorney the opportunity for criticism.  Certain issues must be proven as directly relevant, while others must be disproven, if a report is to carry any impact.

The arbitrary evaluation of all 22 odd floors of run-out condenser water pipe for a high rise office property, and a finding of severe corrosion requiring pipe replacement in every example, still opens the opportunity for opposing counsel to argue that all even floor piping is in perfect condition.  A test procedure taking 12 measurements for record will open questions and criticism to why not 10 or 15.

Widespread failure at threaded fittings at a fire sprinkler system, while the pipe is ultrasonically defined as being still at new pipe specifications, points to an installation error rather a microbiological contamination through the water supply.  A failure at a never used by-pass line, where ultrasound defines the remainder of the condenser water system in near new condition, defines an engineering design flaw, rather than a failure by the chemical water treatment contractor.

Anticipating such legal questions in advance, therefore, and eliminating them from debate, becomes almost as important as the integrity of the final report itself.

Remediation Options

Originally, and for many years, CorrView International, LLC just presented the facts of our investigation, an interpretation and explanation of such facts and potential impact to their property, and nothing more.  We did not recommend corrective measures, helpful products, or contractors of any type.

We would later learn that others promoted a resolution to the problem which best suitedtheir profit line, but rarely contributed to solving the client’s problem.

Filtration experts recomended full flow sand filtration units to small closed chilled water systems; blowing down expensive hydronic heat transfer antifreeze in one example.  Contractors recommended unnecessary pipe replacement, or worse – incorrect but well received simple solutions leaving the true corrosion problem to continue.  The lack of dielectric insulators have a well documented and very localized impact at smaller threaded steel to brass valve connections, and are not in any way associated with runaway corrosion activity at a 24 in. main condenser water riser.  Adding dielectrics at small threaded lines as a solution to 24 in. mains which are corroding at 12 MPY is therefore a worthless undertaking.

Recommending additional filtration to a facility feeding only liquid chlorine into their cooling system due to Legionella fears and dissolving their steel piping as a result is not the appropriate response.

Water treatment contractors, sometimes responsible for the problem and always turned to for advice, often fail to correct the issue.  Minute increases in chemical levels will not improve corrosion control when 1/2 in. thick iron oxide rust tuberculation remains on the pipe surface.  In some examples our findings have been discounted, in others our report tossed in the trash.

Subsequently, we began to offer advice and contact information to other sources whch we knew would place our client’s interests first.  We now offer recommendations toward water filtration, laboratory analysis, and other areas that we believe are helpful to our clients in solving their problem.

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Never An Easy Question / Rarely A Simple Answer

Answering the question of how thick a specific area of pipe is where the client is pointing their finger at a small circled spot is an easy question no competant UT investigator can fail at performing.

Identifying the condition of a building’s entire condenser water piping system, its rate of corrosion, estimated remaining service life, overall condition, immediate and long term vulnerabilities, areas of impending failure, and potential corrective actions, is far more difficult.  In virtually every investigation we have been involved, we have entered the facility knowing nothing of its condition, and left with a full understanding of the issue, and with data necessary to produce a thoroughly informative report.