Stress Cone Application Procedures using Tape
Stress Cone Application Procedures using Tape
(OP)
Can anyone provide a link or instructions or a reference document that gives instructions on how a typical HV stress cone is created using tape only.






RE: Stress Cone Application Procedures using Tape
ht
Some utility companies still insist on tape terminations.
RE: Stress Cone Application Procedures using Tape
I'd try contacting 3M. They probably have instructions available.
RE: Stress Cone Application Procedures using Tape
Also try contacting good electrical contractors in your area who do medium voltage cable splicing and terminaitons, I am sure their HV electrician carries the instructions.
RE: Stress Cone Application Procedures using Tape
I know. I've built them from scratch myself, and I've used the kits. It is a long, time-consuming job to do one by hand. Using the kit is much faster. I don't see any high rate of failures form the kits if they are properly applied.
Of course, you need a wide selection of kits for different cable types, sizes, voltages, etc., where one big cabinet full of tape will work for everything...
old field guy
RE: Stress Cone Application Procedures using Tape
Someone in Okonite probably has details for making stress cones. Call them up, it may give them a laugh.
Oldfieldguy is right. We use to allow 8-12 hours per stress con, now it's 1-1/2 to 2 hrs max per termination.
RE: Stress Cone Application Procedures using Tape
See http://filur.net/PDF/3M/Scotch%202220.pdf
Oldfieldguy:
Sometimes we still use the old tape kits to terminate cable ends or to join cables. But I have to agree with you, I do not think there are a lot of guys who still can do a tape termination/joint, and yes, it takes some time.
Regards
Ralph
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RE: Stress Cone Application Procedures using Tape
RE: Stress Cone Application Procedures using Tape
I can hand tape. I keep the skills up even though I don't do it often. Some places still demand hand tapped splices and terminations. When done right they will out last the kits. A high voltage contractor in my area will guarantee kits as long as the manufacture guarantees the kit. They with guarantee their hand taped splices and terminations for the life of the cable.
They find a lot of bad kits when performing partial discharge testing. Mostly due to workmanship issues. So they do a lot of work cutting of kits and installing hand tapped terms in their place.
If you buy the 3M tape kits they come with directions for standard and "shorty" terminations. The 3M method is similar to a capacitive stress relief system as apposed to a geometric "stress cone." The "shorty termination is great where you are in a really tight place. You can make a 15KV termination that is only about 10" long as apposed to the standard 3M taped term that is about 23" long.
RE: Stress Cone Application Procedures using Tape
I've found quite a few bad installations of stress cone kits. The problems generally fall into two categories: poor cable prep: not removing all the semiconductive layer and its residue from the cable, and second, failure to keep surfaces clean and dry before installing the kits.
In my field experience, we didn't do partial discharge testing. We applied a very specific regiment of DC hipot testing, and we found stress cone "issues" that would have "passed" a go/no-go hipot test using a less rigorous application.
And, yes, I do know of hand-laid stress cones that have been in service almost fifty years... I also know of some that didn't make the week... They depend to a very large extent to the expertise and attention of the electrican making the application. The kits remove a large chunk of the expertise, but not all of it, and they still require care in installation.
But, hey, if it was easy, we'd let anybody do it...
old field guy