managing sf6 gas leaks in circuit breakers - dilo · managing sf6 gas leaks in circuit breakers ......

www.dilo.com - www.dilodirect.com

Zero Emissions. No Substitutes.

DILO 2nd Annual SF6 Gas Management Seminar Tampa FL, November 2017

The true art of SF6 gas leak detection and leak

seal

Managing SF6 gas leaks

in Circuit Breakers

Steve Wickman, PE electric utility independent consultant

John Edmon TDS-Transmission & Distribution Services

November 15, 2017

http://www.dilo.com/

http://www.dilodirect.com/

© January 2013

Our story for you today

SF6—what is it?

Why SF6 in electric utility apparatus?

Some history

SF6—good stuff

SF6—bad stuff

SF6 leaks—find them and fix them

Steve‘s experiences with SF6 CBs

© January 2013

SF6...what is it?

Sulfur Hexafluoride

Sulfur hexafluoride (SF6)

is an inorganic, colorless,

odorless, non-flammable,

extremely potent

greenhouse gas, which is

an excellent electrical

insulator. SF6 has an

octahedral geometry,

consisting of six fluorine

atoms attached to a

central sulfur atom.

© January 2013

Some history

Why SF6 in electric utility apparatus?

© January 2013

In the early 1950s high-voltage CBs of bulk oil

configurations were becoming the norm

These OCBs had an exemplary record but the

possibility of failure, and the risk of explosion and

oil fires existed

Systems grew & HV OCBs were located

increasingly in urban areas and the consequences

of OCB failure gained importance

© January 2013

In the early 1950s the New York Consolidated

Edison Company (Con Edison) in particular started

to push for an oil-less breaker design

In response to this oil-less breaker need, the

Westinghouse Electric Company initiated a program

to develop the GCB using SF6 as the insulating

dielectric & interrupting medium, transforming the

breaker industry

Thirty years later every manufacturer of H-V

breakers adoped SF6 as the medium of choice

© January 2013

Early Installations

PP&L 230kV GCB at Brunner Island substation the first SF6 CB placed in commercial service

© January 2013

Early Installations

ConEdison Hellgate substation May 1960 first two installed SF6 GCBs 138kV 10,000MVA

ConEdison GCB failure February 1961, previous experience with oil CBs indicated that total or near total destruction occurred

This SF6 CB failure was repaired & the CB restored in two days and subsequently ConEdison placed their first substantial order for 138kV SF6 CBs

© January 2013

The good stuff...

Higher dielectric strength than air or

nitrogen

Provides for compactness in the

design of equipment

SF6

The bad stuff...

Found to be the most potent

greenhouse gas known to date

Emitted into the atmosphere it

accumulates in an undegraded state

for centuries

© January 2013

Bottom line...

Allowing it to leak freely into the

atmosphere is not a good thing

SF6

US EPA regulations...

Develop SF6 emissions reduction

strategies

Inventory of SF6 using eqiupment

Estimate current emissions

© January 2013

SF6—got leaks?

SF6 leaks—find them and fix them

© January 2013

SF6 Leak Detection

© January 2013

SF6 Leak Survey & Sketch

© January 2013

External clamp

Leak Repair Technique on SF6

Apparatus

© January 2013

External clamp

© January 2013

Clamp repair concept drawing

© January 2013

External clamp

© January 2013

SF6 piping leaks in GCB control cabinet

© January 2013

SF6 piping leaks—typical measurements

© January 2013

SF6 piping leaks

© January 2013

GIS leaks

© January 2013

Initial leak detection can be performed with CB in service

Detailed survey and measurements without disassembly of CB

Clamp design and fabrication performed in a day or two and air freighted to the worksite

Repairs completed in a day or two with minimal outage time and NO degassing of the CB required...depending on customer safety/work practice requirements

SF6 leaks-find them and fix them

© January 2013

• TRANSMISSION & DISTRIBUTION SERVICES, LLC28369 DAVIS PARKWAY, SUITE 401

WARRENVILLE, IL 60555

P∙775.586.8300

F∙775.586.1105

Steve Wickman

630.853.3104

[email protected]

John Edmon

775.240.1319

[email protected]

© January 2013

John Edmon…44 years in the Leak Sealing

business…starting out working for leak

seal firms working in the petrochemical

and electric power house industry. In

1988, upon the suggestion of an Electric

Utility equipment specialists John worked

with at a power plant on the west coast of

the USA, he developed his technique for

sealing low pressure leaks, initially in large

power transformers. The techniques then

flowed over to CBs initially oil CBs. As the

SF6 dielectric medium became more

prevalent in CBs in the industry, John

started applying the same techniques to

SF6 gas apparatus.

John Edmon

© January 2013

Steve Wickman, PE…37 year career as aPower Engineer with CommonwealthEdison in the greater Chicago, IL area.BSEE from Iowa State University and MBAfrom Keller Graduate School ofManagement [DeVry University]. His 40+year engineering career has spanned workexperiences in substation equipmenttesting and commissioning, designengineering, substation construction andoperations management, as well asproject management, work schedulingand work controls areas. Steve is nowworking as an independent consultant inthe electric utility industry.

Steve Wickman

© January 2013

Russell N. (Russ) Yeckley and R. Gerald (Jerry) Colclaser, Jr., “FirstSF6 Breaker Design, Westinghouse engineers tell the inside story”,IEEE Power & Energy Magazine, May/June 2016

references

www.dilo.com - www.dilodirect.com

Zero Emissions. No Substitutes.

DILO 2nd Annual SF6 Gas Management Seminar Tampa FL, November 2017

Presentation By: Steve Wickman and John Edmon

Created On: October 12, 2017

Transmission & Distribution Services, LLC

Suite 401

28369 Davis Parkway

Warrenville, IL 60555

775-586-8300

Managing SF6 gas leaks

in Circuit Breakers

http://www.dilo.com/

http://www.dilodirect.com/

managing sf6 gas leaks in circuit breakers - dilo · managing sf6 gas leaks in circuit breakers ......

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