Small Talk Tuesday: The Power and History of Insulators
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- Опубліковано 30 лип 2024
- Transcona Museums' Assistant Curator Jennifer takes you through one of her favourite collections at the museum, our insulators. She talks about how to identify type, style, colour, rarity and more while also showcasing some examples from our collection.
Original Small Talk recorded October 13, 2020
Re-recorded October 17, 2020, due to poor audio quality with the original recording. Questions asked during the first recording were covered in this recording.
Very interesting and glad you were able to find out some info on your insulators.
Some additional info:
The purple insulator is actually the bottom half of a 2-piece "transposition" insulator (CD 191), which was used to cross telephone wires every few poles to eliminate cross-talk between circuits. CD 190/191. (like in slide at 21:15) The top is a bit chipped but can see some original molded contour left. This went on the wood pin first, then the top piece was screwed on second. Mostly these disappeared by 1900 in favor of single-piece styles, or use of a crossover bracket mounted on the crossarm, with 4 insulators.
Ohio Brass was based in Mansfield OH, and are actually still in business today, under the Hubbell organization. OB makes mostly polymer strains, lightning arresters, and cutouts these days.
Fred Locke started making porcelain in the 1890s and was one of the first in the US to make higher voltage porcelain in quantities for early power projects. His early insulators were made by Brookfield Glass in NY/NJ until he got the porcelain mfg process developed. In the 1930s he is credited for inventing "borosilicate glass", aka "boro-porcelain", aka Pyrex high temperature glass. Corning acquired the patents and started making cookware as well as insulators out of the glass.
The date May 9, 1893 refers to the patent granted to Hemingray for the drip points on the skirt. The skirt(s) themselves were referred to as "petticoats" since they resembled the petticoats on the dress skirts of the time. I believe they also introduced the inner petticoat/skirt style on insulators also.
The grooves on the Montreal insulators (Withycombe) were intended to reduce damage to the body of the insulator from rocks or other projectiles thrown at them. There is a similar design patented by Bain, which intended to increase surface area of the lower skirts and increase the leakage path, to reduce current leakage from the wire.
The yellow-green Brookfield is an early telegraph insulator, CD126, referred to as a "blob top". Early telegraph insulators are pretty rare in such bright colors. Almost all were light aqua glass at that time, after 1865.
Manganese was added to glass as a "clarifying agent", to make the clear glass more clear. Problem is manganese reacts with sunlight and turns the insulator purple eventually.
"Surge" insulators I believe were made by Hemingray but marketed as a private system for insulating electric fences. Thus the small size.
Very nice presentation. Thank you.
thank you for sharing
15:03 The purple one is actually the bottom part from a 2-piece transposition style insulator.
The CD162s, aka Signals, shown are commonly seen on household electrical service drops, railroad signal lines, and basically a general purpose low voltage (up to 2,400 volts) use piece. Pioneering electric distribution systems used these on their 2,400v/4160D systems. Modern distribution is at 7200v, 14,400v or another similar voltage. As a side note, the one you show after the blobtop Brookfield is also called a signal insulator. A cd133 or 134.
35:15 That appears to be a two-piece transposition, not "physically altered." Fantastic video!
You have many rare ones there, but there are a few that were common. And there are some insulators that are basically worthless (Hemingray 42s 9s and 17s) the purple broken one is frost popped meaning it was upside down water got into it and froze and broke it, but that is one of the most desirable colors. If it says petticoat that is to show that there are multiple skirts, and Dominion was a Canadian company that made knock-off Hemingray styles. And the glass insulator made by Locke is very rare, as almost all Locke insulators are porcelain.
Do you know who the first insulator manufacturer was?
@@kotaman232 The earliest insulators normally didn’t have any markings so no one knows who made them! Back in the 1860s they would be made at a small local glasshouses or pottery shops.
@@EJBuddy Oh wow. How cool. I'm just getting into line work (becoming a power lineman) and want to start collecting insulators because I love the history. How should I start my collection?
@@kotaman232 yard sales, flea markets, and thrift or antique stores are the best places to buy insulators, you can also hunt for them in the wild, usually along old railroad tracks where the telegraph lines used to be. There are several videos on UA-cam of insulator hunting in the wild, just find old telegraph pole sites, then start looking/digging.
Very educational, indeed. But the speaker became very annoying when every 3rd or 4th word was "Um".
I would like to hear this presentation. I am sorry, but I cannot stand listening to a string of sentences all of which begin with "UH." It just grates on me. So I am clicking off after 4 minutes.