Wet, Wetter and Wettest

Dear Soggy Froggy,

I have two areas under consideration for rejuvenation next year.

• The first is a sub-division with 40 year-old cable that is in relatively dry sandy soil.
• The second sub-division has 15-20 year-old cable that is in very wet, swampy soil.

All other things being equal, which area would enjoy the greatest benefit from rejuvenation? Is there any data to support the recommendation? I hypothesize that the cables in the swampy soils should be injected first, since those cables are constantly in water and injecting them might yield the greatest benefit.

Wet, Wetter and Wettest

Dear Wettest-

It’s true that I have a personal preference for the swamp, but I won’t let that predilection alter my advice. This is a really great question because the wetness of the soil at one meter depth is not often discussed and often misunderstood. Fortunately one of my colleagues wrote a paper cited below that unearths the truth of the matter.

Bertini, “Molecular Thermodynamics of Water in Direct-Buried Power Cables,” IEEE Electrical Insulation Magazine, Nov/Dec 2006.

I would encourage my readers to review that paper in its entirety as it dispels many common myths. However, I asked the author to summarize the portion of the paper that relates specifically to your query and he has done so in a YouTube video. Watch this video and learn why both populations of cable are equally wet.

In your inquiry you say, “All other things being equal.” But are they really equal? I would suggest that the first criteria should be: Which of the two areas has had the greatest reliability issues per foot of installed cable? If reliability is equal, I would use age as the next best predictor of future performance.

Forever wet,

Thermo B. Frog

Suitable for Treatment

Dear B.F.

We’ve taken some photographs of cable samples identified with off-line PD testing.  I was hoping to get your opinion of the cable and if injection would be able to address these issues.

·        On two samples, we found the XLP insulation was a greenish color.  We’ve never found cables discolored before and it had an odd odor.  Upon wafering and dying the sample, quite a few trees were found.

·        On three samples, we found spots where a hole was burned through the semi-con layer and dirt had gotten between the semi-con and insulation, causing some deep pitting.

I’ve attached some photos of the issues.  Neither of these cables has been treated, but can they? Let me know what you think.

Wishing you well,

Wisconsin

——————————————————————————————————————————————————————

Dear Wisconsin-

First off – green is a lovely color and you should be proud of your sample’s hue. The green color proves that the insulation compound manufacturer included anti-oxidants in its formulation and is generally an indication of recent heat exposure. The sulfur-based anti-oxidants break into by-products as they do their job. Some of these by-products absorb red light, leaving a predominantly yellow to green hue. The insulation may by 4201 made by Union Carbide, now Dow Wire & Cable. Click here to check out a fact sheet put out by the Dow folks called:

Color Indicates Presence of Antioxidants in XLPE Insulation Compounds

With regard to the odor, I can’t answer definitively for two reasons. One, you did not send me a sample and two, frogs are not known for their olfactory prowess. I can, however, speculate. The sulfur-containing anti-oxidant by-products are called thiols or mercaptans and have strong garlic-like odor. I have a cat at my house with an exceptionally keen nose. If you send me a stinky sample I can ask her to identify the chemistry involved. I hope it does not smell like tuna fish — she might gnaw on it. See "rats" below.

With regard to the water trees, you will find those in every solid dielectric cable. Water trees are the predominant cause of solid dielectric cable failure. Fortunately, Novinium provides fluids that can reverse the damage caused by water trees and replace the anti-oxidants that have been consumed over decades of field aging.

·        Click here to learn how you can know that water trees are the predominant cause of cable failures.

·        Click here to learn how you can be confident that rejuvenation will reverse the damage caused by water trees.

·        Click here to learn how Novinium^®-brand Ultrinium™ fluid can replenish the anti-oxidants in aged cable.

Deep Pitting

I don’t know if the cable with the holes in it smelled like garlic, but the rodents that chewed on it must have liked the odor.  I doubt that the meal was satisfying. I am fond of rodents. An adult mouse fills my belly for the better part of a week, but I might have taken a pass on the gal that was chewing on your cable. Shreds of polyethylene in her belly would end up in mine and would undoubtedly upset my delicate digestion. I suspect the rat stopped chewing when she started to feel a tingling in her mouth – those were partial discharges. Persistence would have led to an untimely end. That’s how I know the rat was a female. A male rat would not have been smart enough to back off when he felt the tingles … in fact they probably would have only encouraged him more.

Here is a question for you, Wisconsin. How many cables had to be examined to find these rodent bites? If rodent damage is rampant in your service territory, off-line partial discharge testing might be a useful tool to find where the rats reside. It is true, that rejuvenation cannot address rodent damage, but how prevalent is this failure mode? For some insight on that question check out my three-part postings of January 2012 …

Failure Causes I, Failure Causes II, and Failure Causes III.

The Novinium masters of reliability have been involved in the injection of many millions of cable feet. Cables with water trees, with or without interesting color and odor, are handled easily and these represent the frog’s share of the root causes of cable failure. Add in component issues addressed by rejuvenation and a tiny minority of potential issues are left unaddressed. It is for this reason that more than 99.4% of all cable treated by Novinium enjoy failure-free reliability.

Never put anything in your mouth that can kill you,

T. B. F.

Failure Causes III

In my January 24^th post, “Failure Causes I,” I provided a partial answer to an inquiry from Colorado Querier. Colorado sought to understand if rejuvenation technology was appropriate for the “many types of aging factors” from which his firm’s circuits might suffer. We learned that 39% or more of all circuit failures are component failures and that these reliability issues are directly addressed with a rejuvenation program.  In yesterday’s post, “Failure Causes II,” we learned that more than 78% of the cable failures, which represent over 60% of the circuit failures are directly caused by water trees.  78% times 60% yields 47%. Water trees are the root cause of more than 47% of circuit reliability issues. Taken together (39% plus 47%) component issues and water trees account for more than 86% of all circuit reliability issues. We could stop right there, because 86% could be characterized as the vast majority. We could stop right there, because of the over 100,000,000 feet of cable rejuvenated over the last two-and-a-half decades, over 99% continue to provide reliable service. Cables treated by Novinium enjoy a post-injection failure rate less than half that of the industry-wide figure. We could stop there, but we won’t. The Novinium masters of reliability strive for post-rehabilitation reliability perfection.

If component issues and water trees represent the frog’s share of reliability root causes, what are the secondary issues? And how does rejuvenation technology address, or not address, these issues?

Neutral Corrosion

The occurrence of neutral corrosion within the population of bare neutral cables is 100%.  But don’t despair, the occurrence of neutral corrosion that creates safety or reliability issues is an order of magnitude less significant than circuit failures from all other causes – that is, generally 1-2% of cables suffer substantive neutral issues. Click here to check out my July 7, 2010 post along with its links to other published works. Even though the neutral corrosion issue is less significant than many assume, the good news is that neutral corrosion is both detectable and addressable. In fact, the Novinium masters routinely detect and repair neutral corrosion.

Thermal Issues

When cables are heavily loaded over sustained periods the insulation loses anti-oxidants and plasticizers. Oxidative degradation and polymer embrittlement contribute to a decrease in dielectric strength and in severe, but rare, cases may lead to cracking of the insulation. Designed to stay in the insulation for decades after injection, Novinium’s Ultrinium™ 73X fluids include anti-oxidants (AOs) and plasticizers. These materials all but halt oxidative degradation and embrittlement. Anti-oxidants have also been proven to slow the rate of water tree growth and increase the inception voltage of electrical trees. Click here to learn more about anti-oxidants in my March 14, 2011 post, “AO, AO … It’s home from work we go.” If the insulation gets hot enough the conductor may migrate and the insulation will become eccentric. These eccentricities usually manifest themselves at tight bending radii. The Novinium masters identify and remove most excessively bent cable sections. These most commonly occur near terminations or accessible splices and these areas are inspected during pre-injection preparation. Novinium^® brand rejuvenation addresses all of these thermal issues.

Halo

Halos are unavoidable when a cable is thermally cycled in the presence of water. Thermal cycling creates micro-voids in the middle radius of the insulation driven by the “Molecular Thermodynamics of Water in Direct-Buried Power Cables.” Click here to view the paper by the same name from IEEE Electrical Insulation Magazine (Nov/Dec 2006). The collection of voids formed this way is referred to as a halo. In the absence of water trees or some other defects, a halo does not lead to failure, because the halo size is limited by the molecular thermodynamics of water in the polymer. None-the-less, rejuvenation reverses most of the dielectric degradation caused by halos by filling the micro-voids with more compatible organo-silicones. Novinium^® brand rejuvenation addresses halos.

Manufacturing Defects

Voids, protrusions, contaminants, eccentricities, and skipped shields are “unwanted features” of a new cable. With the possible exception of skipped shields all of these unwanted features are in every cable. Fortunately for your newer purchases the magnitude of the defects is low enough that the cable can provide reliable service for its design life. For both your new cable purchases and your 30- and 40-year-old legacy purchases if the defects are large enough the cables will fail early in their lives … these kinds of defects yield what statisticians call infant mortality.  Your decade-old cables have been screened by operation of substantive manufacturing defects – those that will actually cause a failure without an accompanying water tree. In short, manufacturing defects are everywhere, but in legacy cable their manifestation is a water tree growing from the defect. Rejuvenation directly address the water tree and Novinium Ultrinium™ 73X brand rejuvenation includes patented stress grading components, which directly address stress-enhancing defects. Click the links below to learn more about stress grading …

Installation Defects

Excessively tight bending radius, excessive pull force, and exterior abuse rendered during installation are analogous to manufacturing defects. Serious problems manifest themselves shortly after installation. If an installation defect survived for several decades it is not so serious that it cannot be addressed by rejuvenation technology, particularly technology that includes Novinium patented stress grading chemistry.

Physical Damage (post-installation)

Frost thrust, dig-ins, and critter attacks can occur at any time. At Novinium we have seen insect attacks and rodent attacks. Amphibians have never been a problem. In the case of critter attacks, these usually occur near terminations and hence are often discovered and rectified as a routine matter during a rejuvenation program.  Dig-ins and frost thrust are generally not discoverable, but follow a pattern similar to manufacturing and installation defects. Cables struck with significant damage fail shortly after the event, insignificant damage may be mitigated by rejuvenation. In summary, rejuvenation mitigates, but does not prevent all failures resulting from post-installation physical damage. Rejuvenation with stress grading technology such as that found in patented Novinium Ultrinium™ 73X brand rejuvenation fluids provides superior mitigation.

Testing Induced

My faithful readers know that this frog is not a devotee of diagnostic testing. The fundamental problem can be summed up thusly:  None of the technologies can reliably discriminate between cables which will fail in short order and those which will not. The rejuvenation program alternative puts a final nail in the diagnostic coffin, because components will all be changed anyway. What sense does it make to find out if the components are good or bad? Since over 99% of rejuvenated cables don’t fail when no diagnostics are utilized and the extension of life is 5-20 times longer that the retesting horizon, paying for a diagnostic is difficult to justify.  If all of that were not enough many diagnostics test induce defects! Electrical trees can be initiated directly by high voltage methods such as off-line partial discharge or indirectly by inducing space charge with DC methods. Even though it makes no technical sense to test, rejuvenation does mitigate the damage testing inflicts on cables if rejuvenation is given some time to improve the dielectric performance of the cable.  For SPR that is about a week; for UPR it is best to wait for at least a year. To explore diagnostic testing further do a key word search on my blog for “diagnostic testing.”

Insulation Shield Separation

Loss of adhesion between the insulation shield and the insulation is a rare occurrence and is the only fault mode not addressed or at least mitigated by rejuvenation. This frog can count on one front paw, and I only have four toes on that paw, the number of failures where the loss of insulation shield adhesion was the cause of failure. These few observed failures suggest that chemical contamination of the soil causes swelling of the shield material and loss of adhesion. Transformer oil or motor oil spills are suspected culprits. If you have a bunch of these kinds of failures on your hands, you have a potential Love Canal situation and you are going to be excavating the whole neighborhood.  No need to treat the cable.

Summary

Advanced cable rejuvenation provided by the masters at Novinium has a proven track record of 99.4% post-rejuvenation reliability. Almost all known causes of solid dielectric underground cable reliability problems are either directly addressed or mitigated. The sole exception is insulation shield separation, which is incredibly rare.

Broad Spectrum Reliability,

T. Bull Frog

Failure Causes II

In yesterday’s post, “Failure Causes I,” I provided a partial answer to an inquiry from Colorado Querier. Colorado sought to understand if rejuvenation technology was appropriate for the “many types of aging factors” from which his firm’s circuits might suffer. In yesterday’s post we dealt with circuit failures caused by connected components, rather than the cable itself. Today we will focus on cable failures.  First a disclaimer – it is often difficult to determine with 100% certainty the cause of a cable failure in field conditions. A cable failure is a destructive event that usually vaporizes its own root cause. Those who analyze field failures can examine the cable near its fault for neighboring defects. If a defect or defects are found, the examiner may infer without certainty that a similar defect may have been the root cause of the actual fault. If no substantial defects are found the root cause will surely remain unknowable.

I emphasized “substantial” in the last sentence because at a small enough scale there are always defects. Water trees grow in all medium voltage solid dielectric cables exposed to moist conditions. Unless you have hermetically sealed metal sheaths, those would be your cables! Water treeing is an oxidative process, but even where there are no water trees, oxidation of the polymer occurs, because oxygen and other oxidizing agents are ubiquitous. Free radicals facilitate oxidation and are common in nature. Cosmic radiation, radioactive decay, and other natural processes spawn free radicals around the clock. On top of those chemical processes there are mechanical strains placed on the cable by thermal cycling driven by load cycling.  Such thermal cycling creates micro-voids in the middle radius of the insulation driven by the “Molecular Thermodynamics of Water in Direct-Buried Power Cables.” Click here to view the paper by the same name from IEEE Electrical Insulation Magazine (Nov/Dec 2006). The collection of voids formed this way are referred to as a halo.  I provide an illustration of a halo and water tree nearby.

What are the primary causes of failure and how is each addressed or not addressed by rejuvenation?

In the frogograph nearby, I show you a subset of field reliability data (Editors note: I have come to call this kind of data – “real, real world!”) gathered by Dr. Steennis of KEMA. The simple logarithmic equation explains 78% of the relationship between maximum water tree length, expressed as a percentage of the insulation thickness and reliability expressed as AC breakdown strength.  AC breakdown strength is not a perfect surrogate for cable reliability, but it’s a pretty good one!  Lightning bolts appear next to each cable sample that failed in service. Water tree length is the single best predictor of reliability. In the same work, Dr. Steennis and his colleagues demonstrated that the laboratory failure of the field aged cables always occurred at the longest water tree, just as a chain fails at its weakest link.

Well over three-quarters of solid dielectric cable failures are caused by water trees. Rejuvenation technology was originally designed to address water tree degradation specifically. In fact, rejuvenation has a proven track record of treating the biggest and ugliest water trees on the planet.  Click here, to check out my October 5, 2011 post, “Water Trees – Too Big to Fail?” In my third post of this series we will examine the other less important root causes of cable failure and consider whether or not those root causes can or cannot be addressed by the application of rejuvenation technology.

Master of Reliability,

T. Bull Frog

Real World I – High K

In my last post of 2011 one of my local fans, Wondering in Western Washington, questioned the veracity of the claims made by UTILX^® in a document titled, “Life Extension Estimate for UtilX^® CableCURE^® Rejuvenation Fluid.”  That document includes 17 pages and many, many claims. In this first of a series of posts, I examine the following set of claims from page 3:

Once the CableCURE^® molecule reaches those sites it performs two important functions. First, it chemically combines with the water, desiccating the water tree site. Second, it polymerizes; the polymeric chain that forms continues to grow until its chain length traps it inside of the water tree structure. Once trapped inside of the cables insulation, it serves as a “high K" style stress gradient reducing the electrical stress amplification that occurs at the tips of the water tree “branches". This two part functionality arrests the growth of water trees in aging cable.

I added highlighting to focus on the words and phrases of the claims that could create confusion; I left all puctuation and grammer errors untouched.  The first two words I highlighted could be characterized as quibbles, but I endeavor to be precise in my language. I am sure the author will appreciate my clarifications, since these claims taken together with others are held out as “irrefutable proof” of CableCURE efficacy. The third highlighted “high K” claim will receive the majority of my attention today.

Desiccating

The CableCURE molecule to which the author refers is phenylmethyldimethoxysilane or PMDMS for short. The chemical reaction of PMDMS with water is well understood. On average each PDDMS molecule consumes about one water molecule.  The effect is real, but the implication of the claim is that this desiccation-by-reaction is one of PMDMS’s two important functions.  It is not. The reaction with water is a necessary precursor to a subsequent condensation reaction. In the next sentence the author refers to this second reaction as polymerization.* Chemical desiccation is not important because the phenomenon is fleeting.  Consider the data reported by another UTILX employee in “The Importance of Diffusion and Water Scavenging in Dielectric Enhancement of Aged Medium Voltage Underground Cables” at the IEEE PES T&D meeting in Chicago, 1994.  Figure 4 and the accompanying text indicate that the water reactive capacity of PMDMS is exhausted at between 54 and 67 days for a 1/0 conductor at 60°C.  At lower temperatures the time to exhaustion might be longer, even on the order of a year or even two. When one is talking about decade-long life extension, a couple of months or a couple of years is not of critical importance. None-the-less, PMDMS does help keep the insulation dry for many, many years, but not by the mechanism suggested by the author. Instead, the mechanism is preferential wetting, which is well described in U.S. Patent 7,976,747 held by Novinium and in the paper “Advances in Chemical Rejuvenation of Submarine Cables” available here. The reason the distinction is important is that only Novinium^® brand Ultrinium™ 73X fluids include components with preferential wetting properties superior to PMDMS. Reducing the amount of water present in the insulation is indeed important, but not all rejuvenation fluids perform the same in water reduction efficacy.

Trap

The word “trap” is too absolute for this frog. Trap implies eternity and it just isn’t so.  In a December 29, 2010 post, “Chain Entanglement,” I explain how the larger oligomers substantially retard the exudation of the rejuvenation fluid, but it is not trapped. As shown in the figure nearby, improvements in rejuvenation molecules patented by Novinium (U.S. patent 7,658,808 and others pending) are designed to stick around in the insulation longer than PMDMS.

High K

There is no agreed-upon definition for High K, when applied to stress grading in power applications.  At 20°C and 60Hz, the dielectric constant or “K” of unfilled polyethylene is about 2.3 and EPR insulation varies from about 2.7 to 2.8 depending upon the specific compound. (See Bartnikas & Srivastava, Power and Communication Cables, IEEE 2000.)  The dielectric constant for PMDMS is 3.2. The dielectric constant of PMDMS is indeed higher than PE and EPR insulation, but using the word “high” is a bit of a stretch.  High K materials are quite often used in shrink-to-fit splices and terminations.  For example, 3M’s data sheet for its Quick Term II Silicone Rubber Termination Kit states:  “The High-K material has a dielectric constant of about 25.”  Pure water has a K of 78. Cyanobutylmethyldialkoxysilane or CBMDAS for short, a patented component of Novinium^® brand Ultrinium™ 73X fluids, has a K much greater than that of water.  3M’s stress control material, water, and CBMDAS are “real life” High-K materials.  I have arranged these six materials in a table nearby for easy reference.

I object to the statement proffered by the author for two reasons …

     1. It is an assertion without proof.  If the author believes that the mechanism he claims is significant with a K of just 3.3, he should provide a calculation or measurement as substantiation.

     2. The PMDMS is replacing water, which has a much higher dielectric constant.  How could that conceivably provide stress grading?  CBMDAS on the other hand, enjoys a K greater than the water it replaces.

Executive Summary

The author of “Life Extension Estimate for UtilX^® CableCURE^® Rejuvenation Fluid” is not a master of the facts. While CableCURE fluid does dry the cable and extend its life, the explanation of why this is so lacks foundation. Stress grading at the microscopic scale is possible with materials that have dielectric constants greater than the water that they replace.  One example of such a material is available only from Novinium and is protected by a U.S. Patent, other pending patents, and their foreign equivalents. While this frog cannot be sure what the author was thinking when he made his claim, I can provide a common-sense recommendation: Do not rely on secret documents that have not been peer reviewed … especially if they include assertions without proof.

Always basking in transparency,

Thermonuclear Bull Frog

*The correct terminology is oligomerization, but I will let that slide.

Really Long Term Life

In my December 29, 2010 post at …

Crazy-Competitor-Claims

Wonderer in the Wilderness inquired …

1. How can Novinium get the same cable life extension without a soak period?  It would seem to me that Novinium puts less fluid into the cable than one would get with a soak period.

In my first post addressing this question I provided an abbreviated answer. We learned from the abbreviated answer that that when Novinium founders conceived of the first generation of treatment fluid over two decades ago, there was a failure to check the relative diffusion rates of the phenylmethyldimethoxysilane (PMDMS) monomer and the condensation catalyst we had chosen to provide long life.  This turned out to be a grave mistake, which we have corrected.  In a subsequent post on January 3, 2011 at …

Catalytic Considerations – Component I

… I provided a more comprehensive answer, but I promised five new posts that would explain the functional improvement of the five kinds of ingredients in Ultrinium™ 732 and Ultrinium™ 733 fluids.  In this last of those five sub-posts, I explain how a component with a really ugly name provides extraordinarily long life.  Chemists call the material found in Ultrinium™ fluids cyanobutylmethyldimethoxysilane (Pronounced: Sigh-an-Oh•butte-ill•meth-ill•die-meth-ox-ee•sigh-lane); we will call it CBMDMS for short.

In the graph nearby I explain the first dimension of why CBMDMS works so well for so long.  The graph plots the “permeation product” of the three most commercially important rejuvenation silanes.  Permeation is the product of the diffusion coefficient and the solubility of the material in cross-linked polyethylene (XLPE).  The rate of fluid exudation from a cable is directly proportional to this permeation product.  Remember that if a fluid exudes out of the cable, it is not providing any life extension benefit.  The lower the permeation value, the longer the fluid will stay in the cable.  The permeation of the primary ingredient in Novinium’s Perficio™ 011 fluid and other older technology fluids is illustrated by the light-blue-colored (upper-most) line over the range of 15 to 90°C.  This fluid is called phenylmethyldimethoxysilane (Pronounced: Fen-ill•meth-ill•die-meth-ox-ee•sigh-lane) by chemists; we will call it PMDMS.  In a recent post, Chain Entanglement, I explained how extending the length of the side chains entangled the silicone in the polyethylene polymer chains and slowed the diffusion.  The orange line shows the advantage enjoyed by tolylethylmethyldimethoxysilane (Pronounced: Tall-ill•eth-ill•die-meth-ox-ee•sigh-lane by chemists) or TEMDMS, which is a result of this chain entanglement.  The permeation rate and proportional exudation rate of TEMDMS, is always lower than that of PMDMS.  At low temperature they are about the same, but at 75°C, the TEMDMS permeates about 5-times slower.  But the focus of this post is the amazing CBMDMS, which enjoys a 25-fold to 45-fold permeation advantage over the PMDMS.  That’s a really big deal!  At 75°C CBMDMS will outlast PMDMS by a factor of 45!

TEMDMS and CBMDMS are available only from Novinium, as their use is protected by U.S. Patent 7,643,977, other pending applications, and their foreign equivalents.

The cyano-group, found only in Novinium rejuvenation products, grades stress in the same way, but at the nano-scale.    Before I explain how this works we need to define a thermonuclear-sized word:  dielectrophoresis, pronounced die-EE-lek-trow-for-EE-sis or DEP for short.  DEP is a phenomenon in which a force is exerted on a dielectric molecule when it is subjected to a non-uniform electric field – the greater the dielectric constant of the material, the greater the force.  The illustration nearby explains how the diverging electrical field near an imperfection imparts a force upon CBMDMS molecules and draws them into the local-region of highest electrical stress.  The presence of the high dielectric constant material smoothes the electrical stress and interferes in several ways with dielectric failure mechanisms:

1.    The local AC stress is reduced, and water trees grow more slowly.

2.    The high electrical fields around space charges are reduced, which reduces the likelihood of UV photon creation and the inception of free electrons.

3.    Any free electrons will not be accelerated to the same energy as they would have been in a greater field.

4.    The reduced local field increases both the partial discharge inception and extinction voltages.

Greater persistence in the insulation and stress grading provide longer post-injection life even in demanding applications.  Performance at high temperature and performance in cables with constrained geometry that limit the amount of fluid that can be supplied, are greatly enhanced by the presence of CBMDMS.

Longer life through better chemistry,

Thermonuclear B.F.

AO, AO … it’s home from work we go

In my December 29, 2010 post at …

Crazy-Competitor-Claims

Wonderer in the Wilderness inquired …

1. How can Novinium get the same cable life extension without a soak period?  It would seem to me that Novinium puts less fluid into the cable than one would get with a soak period.

In my first post addressing this question I provided an abbreviated answer. We learned from the abbreviated answer that that when Novinium founders conceived of the first generation of treatment fluid over two decades ago we failed to check the relative diffusion rates of the phenylmethyldimethoxysilane (PMDMS) monomer and the condensation catalyst we had chosen to provide long life.  This turned out to be a grave mistake, which we have corrected.  In a subsequent post on January 3, 2011 at …

Catalytic Considerations – Component I

… I provided a more comprehensive answer, but I promised five new posts that would explain the functional improvement of the five kinds of ingredients in Ultrinium™ 732 and Ultrinium™ 733 fluids.

In this third of five sub-posts we will explore the role of the anti-oxidants (AO).  Every human knows the benefits of including anti-oxidants in their diets.  I am not as susceptible to oxidative damage, because I keep my temperature lower – that way I do not have to consume foul tasting raspberries and blueberries.  Besides their sickening sweet taste, the antioxidants found in berries are single-shot deals.  A single anti-oxidant molecule consumes a single oxidizer.  What we need for cables is a molecule that quenches the nasty oxidizer and then regenerates itself – indefinitely.  It would be nice for people too, but don’t hold your breath.  For cables the folks at BASF^® and Novinium have a solution.

The primary AO in Novinium’s Ultrinium™ fluid formulations is BASF’s Irgastab^® Cable KV10.  Furthermore all of the components of the Ultrinium UV package have anti-oxidant properties.  These materials were described in To UV or not to UV.  In the vernacular, these UV components are “two-fers” or “two-for-one” ingredients, because they fulfill at least two¹ independent and important life-extension functions.

Antioxidants are included in virtually all modern cable compound formulations.  Originally deployed by polymer compound manufacturers to prevent oxidation during cable extrusion, it has been shown by

Cold blooded and not oxidized,

Thermonuclear

¹Ferrocene and Tinuvin^® 123 are “three-fers.”  Ferrocene is an anti-oxidant (AO), an ultra-violet absorber (UVA), and a voltage stabilizer.  Tinuvin^® 123 is an anti-oxidant (AO), a hindered amine light stabilizer (HALS), and a methanolic corrosion inhibitor.

To UV or not to UV

In my December 29, 2010 post at …

Crazy-Competitor-Claims

Wonderer in the Wilderness inquired …

1. How can Novinium get the same cable life extension without a soak period?  It would seem to me that Novinium puts less fluid into the cable than one would get with a soak period.

In my first post addressing this question I provided an abbreviated answer. We learned from the abbreviated answer that that when Novinium founders conceived of the first generation of treatment fluid over two decades ago we failed to check the relative diffusion rates of the phenylmethyldimethoxysilane (PMDMS) monomer and the condensation catalyst we had chosen to provide long life.  This turned out to be a grave mistake, which we have corrected.  In a subsequent post on January 3, 2011 at …

Catalytic Considerations – Component I

… I provided a more comprehensive answer, but I promised five new posts that would explain the functional improvement of the five kinds of ingredients in Ultrinium™ 732 and Ultrinium™ 733 fluids.

In this second of five sub-posts, we will explore the role of the ultra-violet absorbers (UVAs) and hindered amine (pronounced a-mean) light stabilizers or HALS.  The primary UVA is BASF^®’s Tinuvin^® 1130.  Additionally ferrocene (pronounced fair-O-seen), which was discussed in my last post, Voltage Stabilizer, is not only a voltage stabilizer, but also absorbs ultraviolet photons in the appropriate wave length.  In the vernacular, ferrocene is a “two-fer” or a “two-for-one” ingredient, because it fulfills two independent and important life-extension functions.

As you know, frog skin is very sensitive, and so I slather on the UVA (sunscreen) every time I am out in the sun – doing so helps keep me beautiful.  Cables buried one meter underground do not need protection from the sun’s relentless ultraviolet onslaught.  They do need UV protection, however, from UV that is created when space charges recombine near the ends of water trees.  Consider for example the work of Bamji, Bulinski, Chen and Densley in the Proceeding of the 3^rd International Conference on Properties and Applications of Dielectric Materials, held in Tokyo in July 1991:

“… at points of electric stress enhancement in the polymer, the light emitted during the initiation phase of electrical treeing is … due to the recombination of electrons and holes injected into the material.  The spectra of the emitted light is in the visible and ultraviolet ranges.  The ultraviolet light can photodegrade the polymer and lead to electrical treeing.”

It is easy for us all to understand how UVA materials work.  They are opaque to UV light.  The potentially damaging UV photon strikes a resonance stabilized structure in the UVA molecule, is safely absorbed, and is converted to harmless heat.  That’s how sunscreens for our skin work too.  On my skin, if I want to stop 100% of the UV photons I need to apply unattractive zinc-oxide in a thick pasty layer – yuck!  In insulation if I want to stop 100% of the UV photons, I need to apply clay – we call those insulations EPR, EPDM, et al.  So UVA materials cannot intercept 100% of the damaging UV photons.

Unlike the common experience we all have with UVA materials, HALS are not within our normal experience.  HALS are free radical scavengers and they are beneficial, because the mechanism of photodegradation involves the creation of a free radical by errant UV photons – a photon strikes an electron and imparts so much energy to the electron that the molecule, to which it was bound, can no longer hold on to it.  A free radical (an unpaired electron in the molecule) and a free electron are created.  Electrons don’t like to be unpaired, and so, they search out other electrons and try to borrow them from their parent molecules.  As they do this, they tear apart innocent molecules and generally there is still an unpaired electron after the damage from the first encounter.  The free radical survives (or spawns a daughter) and creates cascading systemic damage.  HALS quench free radicals, and here is the cool part, they auto-regenerate to a HALS after they kill the free radical.  How cool is that?  I wish they would make HALS for amphibians, because I could take a HALS pill and snack on crickets all day without worrying about the consequences of free radicals ravaging my DNA.

It gets even better.  The word “synergy” is overused in business circles and promised synergies are often quixotic.  The poster tadpole for synergy is the interaction between UVA and HALS components.  Alone, each has a positive effect on cable life, but together they work better than the sum of their parts – one plus one equals three!  Ultrinium™ 732 and 733 fluids and Perficio™ 011 fluid utilize BASF^®’s state-of-the-art Tinuvin^® 123 HALS.  As we learned in the previous post, DMDB Doubts, Tinuvin 123 also stabilizes aluminum strand patina, which all but eliminates the potential for strand corrosion suffered by older injection technology.  Tinuvin 123 provides another formulation two-fer.

For over two decades, UVA and HALS have been included in TRXLPE (tree retardant cross-linked polyethylene) formulations.  See for example U.S. Patent 4,870,121, "Electrical Tree Suppression in High-voltage Polymeric Insulation,” September 26, 1989.  With the introduction of Ultrinium™ 732 and 733 fluids, Novinium delivers improved UV stabilization using the best available technology.  Novinium’s UV package is protected by U.S. Patent 7,658,808 and other pending patents and their foreign equivalents.  Only Novinium rehabilitation technology provides UV stabilization in the proper UV range.  To learn how first generation technology fails to address the UV photons created by space charge recombination, see Section 8 of the CIGRÉ Canada paper of October 18, 2010, “Cable Rejuvenation Mechanisms: An Update.”

To UV or not to UV, that is the question.  Answer:  Come out of the sunlight into the shade; live longer and with greater reliability,

Thermonuclear

 In my December 29, 2010 post at …

Crazy-Competitor-Claims

Wonderer in the Wilderness inquired …

1. How can Novinium get the same cable life extension without a soak period?  It would seem to me that Novinium puts less fluid into the cable than one would get with a soak period.

In my first post addressing this question, I provided an abbreviated answer. We learned from the abbreviated answer that that when Novinium founders conceived the first generation of treatment fluid over two decades ago, we failed to check the relative diffusion rates of the phenylmethyldimethoxysilane (PMDMS) monomer and the condensation catalyst we had chosen to provide long life.  This turned out to be a grave mistake, which Novinium has corrected.  In a subsequent post on January 3, 2011 at …

Catalytic Considerations – Component I

… I provided a more comprehensive answer, but I promised five new sub-posts that would explain the functional improvement of the five kinds of ingredients in Ultrinium™ 732 and Ultrinium™ 733 fluids.

In this first of five sub-posts we will explore the role of voltage stabilizers and partial discharge suppressers, geranylacetone (pronounced ger-an-ILL-ass-e-tone) and ferrocene (pronounced fair-O-seen), which are included in all Ultrinium™ fluids.

Ketone-type (pronounced KEY-tone) voltage stabilizers like geranylacetone have been studied in depth by several researchers.  Most prominent among those researchers is Johann Wartusch.  His work culminated in German patent DE 3017442 of August 3, 1983 and is described in his paper “Increased Voltage Endurance of Polyolefin Insulating Materials by Means of Voltage Stabilization” (IEEE 1980).  Wartusch demonstrated that the presence of geranylacetone increased tree inception voltage over three-fold, and due to its affinity for the polymer, it persists in the insulation for many years.

EPRI studied the tree inhibition properties of ferrocene in TD-145 EPRI Project RP 7830-1, “A new class of additives to inhibit tree growth in solid extruded cable insulation” of March 25, 1976, and concluded:  “Ferrocene completely suppresses treeing and increases the breakdown strength of polyethylene by [at least] 100%.”  Kato and his colleagues obtained similar results and the culmination of their effort was U.S. Patent 3,956,420, Polyolefin (pronounced poly-OLE-e-fin) Composition for Electrical Insulation, May 11, 1976.

In short, geranylacetone and ferrocene are proven tree retardants that can each provide 100% improvements in the dielectric breakdown strength of polymers in which they are dispersed.  Both materials persist in treated insulation for decades and both are found only in Novinium^® rejuvenation fluids.  The use of ferrocene in rejuvenation fluids is protected by Novinium's U.S. patent 7,658,808 and its foreign equivalents.  Other patents are pending.

Occasionally in polymeric insulation, free electrons are created by one of two known mechanisms.

1.    Recombinant space charges near the tips of water trees may generate enough energy to knock electrons out of their orbitals.

2.    Cosmic ray bombardment is the second source of ionization energy that can create free electrons.  For a 1 mm³ cavity such ionization is likely to occur every five minutes. (See Boggs, “Partial Discharge in the Context of Distribution Cable Testing”, ICC minutes.)

Whatever the source of the free electron, in the absence of a voltage stabilizer, the electron will almost certainly be accelerated by the electrical field and may inflict damage to the surrounding polymer.  Voltage stabilizers scavenge these free electrons and let them resonate within their structure.  The resonation allows the excess energy of the electron to be bled off in small, non-damaging quanta. (i.e. infrared photons, which do not have enough energy to damage the polymer.)  When a suitable and stable receptor for the electron (most likely a cation [pronounced KAT-eye-on] generated when the electron was knocked out of its orbital) is found, the voltage stabilizer gives up the excess electron and returns to its original state, ready to deal with the next errant electron.

Stable and able,

Thermonuclear