O-ring Evolution

Dear Erudite Amphibian,

If an O-ring equipped probe of an injection elbow were to break-off or otherwise fail, can we replace it with a standard probe?

Wondering in Washington

Dear Wondering-

The absolute best choice is to replace the damaged probe with an identical probe. Novinium would be happy to provide these probes to you with only a modest markup. If the Novinium masters of reliability are in town, just give them a call as they likely will have spares on their truck. This frog realizes that your question is probably targeting the case when there are none of these O-ring equipped probes nearby and you desire to put the cable back in service. To answer that question it is useful to explain how the O-ring-equipped probe evolved.

In the illustration nearby, I point at a fully evolved O-ring on a probe pin.  In this 2011 incarnation the O-ring is seated in a composite sleeve molded into the elbow throat. The very first injection elbows were invented by my colleague, Glen Bertini and his associate at Dow Corning, Dan Meyer, about 25 years ago.  I wish I had a picture to show you, but I don’t believe any exist of that dinosaur.  The very first injection elbow, used from 1987 to 1989, was a standard elbow with a capacitive test point.  Bertini and Meyer drilled and taped a hole through the capacitive test point and screwed an insulating nylon cap into the hole.  The elbow worked flawlessly, but was properly considered unreliable for long term operation and hence the elbow was treated as a tool.  After the injection was complete the modified elbow was swapped for an unmodified elbow of the same size. There was no O-ring in either elbow.  CableCURE^® 2-2614 fluid, which was (and remains) predominately phenylmethyldimethoxysilane (PMDMS) and has a flash point of about 66°C flooded the bushing on 100% of the applications.  There were no adverse consequences observed.

The next improvement in the injection elbow was the introduction of a dedicated interference fit injection port.  The collaboration between Bertini and Meyer of Dow Corning and Alan Borgstrom of Elastimold yielded two U.S. patents, 4,946,393 and 5,082,449 in 1989 and 1990.  This advancement meant that the injection elbow could be left in place indefinitely … only the injection cap had to be swapped. There still was no O-ring, hundreds of thousands of feet of cable were injected, and there was precisely one problem. Sometime in late 1989 a bushing failed because the CableCURE 2-2614 fluid had dissolved a plastic component within the bushing. Elastimold and Dow Corning immediately tested the fluid and bushing component compatibility and found no issues that detracted from the elbow-bushing compliance to IEEE 386™.  See Elastimold test reports 102-17-9011 and 101-17-9010, both dated January 1990. It turns out the single bushing that failed was an anomaly – not a large production bushing. None-the-less, Dow Corning and Elastimold decided that even though incompatible bushings would be a rarity, it would be prudent to add a seal to the system to minimize the probability of adverse fluid interactions within the bushing.  An O-ring was added to the probe in about 1991.  The rubber O-ring was not seated in a rigid collar and hence a small deflection of the probe pin would allow a leak. This problem was minor, however, because when the elbow was seated on the bushing it was held in a perfectly centered position.

Two years later in about 1993, UTILX^® Corporation, after licensing CableCURE technology from Dow Corning, unveiled another Bertini inovation (U.S. Patent 5,372,841), which was called CableCURE^® XL fluid. While XL fluid brought significant dielectric performance gains, it suffered from a much lower flash point and it wasn’t too long before the imperfection of the O-ring seal lead to fires when a fluid-filled elbow was switched.  Over the course of the next decade, the seal was changed several times to improve its robustness.

Novinium fluids are not flammable. See my November 2, 2011 post “Fluid Flammability” for more on this subject. If you are using a flammable fluid from another supplier, this frog would highly recommend using only O-ring probes.  With Novinium fluids the risk is minimal.  There is a low risk that fluid will get into the bushing after the injection has been completed, and that risk decreases as time-since-injection advances.  There is an even lower risk that Novinium fluids in the bushing will create any safety or reliability issues.

In 2012 Novinium and our component manufacturing partner will be introducing an entirely new injection device suitable for both unsustained pressure rejuvenation (UPR) and sustained pressure rejuvenation (SPR).  It will be inherently leak-free. When the new injection device becomes commercially available, switch to it and your question will become moot.

Evolving to be safer, faster and better,

Thermo

Soaking:  Diminishing Returns I

Dear Greatest of Soakers,

It seems odd to me that for one who spends so much time soaking herself, that soaking cables is anathema to your firm’s culture.  When is it appropriate to soak a No.2 compressed URD cable?  If I do soak, for how long should I soak?

Geometrically constrained,

Alaskan Amber

Dear Amber-

You ask more questions than any of my other numerous fans.  I like that, except I have been told that some find the questions and the answers too technical.  My response to those critics is to ask your own questions.  If you ask a simple question, I will provide a simple answer.  This Amber guy is cool, his question is appropriate, and a proper answer it is going to require two posts.  Here is the first …

I can see why you might have been misled to believe that I am anti-soak, but that characterization is unfair.  Let’s set the facts straight:

1.   Novinium has a pile of patents that make soaking unnecessary, even for multi-decade life, for all but the most geometrically constrained cables.  I will define “geometrically constrained” later.  The following technological advancements, which I have expounded upon in past blogs, mean that even without a soak, Novinium technology will last longer than the two-decade old approach used by less enlightened purveyors of rejuvenation:

a.   Catalyst improvements were chronicled in Catalytic Considerations I and Catalytic Considerations II.

b.   Novinium Voltage Stabilizers are not present in older approaches.

c.    Our ultra-violet package, which retards the formation of electrical trees was laid out in “To UV or not to UV.”

d.   The tremendous power of effective anti-oxidants present only in Ultrinium™ brand fluids was described in “AO, AO … its home from work we go.”

e.   “Chain Entanglement” dramatically slows the exudation of treatment fluid from the cable and is another patented Novinium innovation.

f.     The “Really Long Term Life” afforded by still another patented Novinium innovation delivered by an ultralow permeability component.

2.   The folks at Novinium invented soaking over two decades ago.

3.   Novinium does soak cables under certain circumstances.

We do consider soaking as a last resort, however, because soaking has two drawbacks.  First, and in order of importance to us, there are safety compromises associated with leaving a hydraulic connection to an energized cable for a long period of time.  I enumerated these risks in my post:  “Greatest Rejuvenation Risks.”  For live-front applications, Novinium can greatly mitigate these risks with a piece of proprietary technology called an HVFI or high-voltage fluidic-interface.  Click here to view a HVFI test report.  Second, there are economic costs associated with a soak period.  In short, a soak bottle with an associated capital cost must be deployed for the duration of the soak period and the injection team has to be redeployed to the site to remove said soak bottle.

Despite these challenges we occasionally resort to soak periods.  The very first consideration is whether the cable to be rejuvenated has a severely constrained geometry.  The “Draft Guide for Rehabilitation and Rejuvenation of Extruded Dielectric Cable” defines constrained geometry in general and severely constrained geometry in particular as follows:

“When the available volume of fluid that can be held in the strand interstices at atmospheric pressure is less than the optimum quantity of fluid to treat the cable, the cable is said to be a constrained geometry cable.  Figure 3-1 [below] shows the three realms of geometry for round (or concentric), compressed, and compact strand cables, namely unconstrained (greater than 20 kg/km), moderately constrained (<20 kg/km and >10 kg/km), and severely constrained (<10 kg/km).”

In practice severely constrained cables are those with conductors of 7-strand and compact 19-strand construction.  If your cables do not have severely constrained conductors, four decades of life extension are possible without resorting to soak periods.

At Novinium we routinely employ soak periods on severely constrained geometry cables for high value circuits with live-front terminations.  Submarine cables provide an example of such high value circuits.  These cables can require 7-figures to replace, so the incremental cost of providing a soak is justified.  Can Novinium make soaking safe in the dead-front applications typical of residential distribution cable?  To answer that question check out my subsequent posts in this series:

Soaking II:  Safety First

Unconstrained by old paradigms,

Thermo

10 Commandments

Dear All-knowing Frog,

I read with great interest your June 9, 2010 post describing the greatest rejuvenation safety risks at …

www.novinium.com/frogblog/post/2010/06/09/Greatest-Rejuvenation-Risks.aspx.

It is clear that injection is much safer than replacement and that the steps Novinium has taken to make rejuvenation safer still are substantial and impressive, but what can be done to mitigate the risk of electrical contact?  Do you have any rules or insights from which I may learn?

Signed,

Praying in Provo

Dear Devout-one,

I sought, and was granted, guidance by the highest of authorities.  When it comes to safety we share all of our best practices with anyone that would like to learn.

The very first Novinium Value is Safety.  It states: 

“Safety is our first priority.  We provide an ever–improving safe work environment for our team members, our customers, and the public.”

The greatest safety risk we face is electrical contact.  If the ten commandments below are followed the team will be safe from all known electrical hazards.  If an individual decides to ignore one or more of these commandments that individual is not welcome on the Novinium team.  Ignoring any of these 10 commandments endangers life. More...

Biggest Risk is Electrical

Dear Soggy Froggy,

What are the greatest risks associated with rejuvenation of medium voltage power cables?

High and Dry in Denver

Dear Dry-

It is true that my beautiful wet skin is a disadvantage near electricity.  That is why I let my journeyman lineman colleagues do most of the work.  I am the brains and the beauty behind them.  Click on the video link below where I demonstrate the greatest risk of rejuvenation – and don’t try this at home.

Rejuvenation is inherently safer than replacement.  When rejuvenating cable the electrical risk is the biggest risk by far.  For a thorough description of all of the dimensions of rejuvenation safety, including even more about electrical contact, my colleagues, Rich and Glen provide an 84-page treatise, “A Comparison of Rejuvenation Hazards & Compatibility.” That tome is available on-line at:  www.novinium.com/pdf/papers/Rejuvenation_Hazards_Analysis.pdf.

From that document I have copied the graph below.  Don’t worry there will not be a quiz and you do not need to pull out your reading glasses.  The risks are enumerated and categorized in the aforementioned tome, and the risk identified as “1.1” is the electrical contact risk.  You will find 1.1 in the upper-right-hand corner of the figure.  All of the other risks pale by comparison and lie below and to the left of the electrical contact risk.  The scales are logarithmic, so differences in risk assesments are larger than they appear.

Patented Novinium technology reduces exposure to this risk in several ways.  First the period of time that injection bottles are connected to energized cables is considerably less than with older approaches.  The probability that a leak will occur is related to the length of time that a feed or a soak bottle is connected to a cable.  Whether utilizing Novinium’s patented sustained pressure rejuvenation (SPR) or the older unsustained pressure rejuvenation (UPR), Novinium’s patented catalyst technology eliminates the need for a soak period completely.  Approaches that don’t utilize Novinium’s patented catalyst technology require soak periods of 60 days or more for most 7-strand and 19-strand conductors.  Utilizing Novinium technology typically reduces the exposure to leaking fluids over 60 times. When UPR is utilized Novinium also uses patent pending technology to mitigate the probability of injection port flashover.  The picture nearby shows a low amperage laboratory flashover.  The mitigation technology is called a reticular flash preventer or RFP.  This issue and the solution are described in some detail at ...

http://www.novinium.com/pdf/papers/Advancements_in_200-amp_injection_elbows.pdf.

My advice to you is to never compromise safety.  State-of-the-art patented and patent pending technology, soak-free injection processes, and RFP flash-over prevention are available only from Novinium and our partners.

Minimize your exposure,

Thermo

Flash Point & Flammability

Dear Wet One,

What is a flash point and how important is the flash point in rejuvenation safety?

Charred in Columbus

Dear Charred-

I like to keep warm more than the average girl, but there is warm and then there is warm.  To keep cool I keep my skin moist and I avoid situations where I could possibly be exposed to fires.  Before I answer your query, let's review some principles.  There are three things required for a fire or explosion,

1. oxygen (generally in the guise of air)
2. a source of ignition, which is often readily available in electrical distribution and transmission environments, and
3. fuel. More...

Oh mother of all that is green-

Do Novinium Ultrinium™ fluids contain the carcinogen, developmental toxin, and male reproductive toxin benzene as Perficio™ 011 fluid does?

Sleepless in Seattle

Dear Sleepless-

Sleep well in your burrow tonight.  No. 

Perficio 011 fluid is based upon phenylmethyldimethoxysilane (PMDMS) fluid disclosed by U.S. Patent 4,766,011 and invented by a Novinium founder over two decades ago.  PMDMS-based fluid includes up to 100 ppm of benzene, because the PMDMS is a reaction product of an industrial process that begins with benzene.

In contrast, Novinium Ultrinium brand products include starting materials, which are not known carcinogens, developmental toxins, or reproductive toxins, because it is virtually impossible to remove all traces of incompletely consumed starting reagents.

Sleeping near Seattle,

Thermo