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Any electrical engineers around here?

We need to do a little favour for some peeps in Russia. Which means finding a customer for their production. And we’ve not the slightest idea what this is nor who would use it:

1 Charpy Impact viscosity, kJ/m2, not less 7.0
2 Bending stress at failure, MPa, not less 110
3 Martens thermal stability, C, not less 250
4 Water absorption, mg, not more 10
5 Raschig flow index, mm, not less 160
6 Specific electrical volume resistance, Om m, not less 1*109
7 Dielectric strength, MV/m, not less 19.0
8 Mass concentration of moisture and volatiles, %, not more 3.0

There’s more of this. And of course it doesn’t tell anyone what it actually is. We keep asking, well, yes, but what the hell is it?

T265 in Russian military terminology.


A phenolic glass composite thermoset plastic.

None of us has a scoobie here. Anyone got any ideas?

32 thoughts on “Any electrical engineers around here?”

  1. Have you tried asking any of the specialist electrical or transformer insulation manufacturers? Even a bobbin manufacturer like Miles-Platts or Formers might be able to help. Ferroxcube might be able to help as well.

  2. That’s sorta what I’m trying to find out. What the hell is it so that I can work out who to go talk to?

  3. Is something lost in translation?

    Your charpy impact viscosity appears to be an energy absorbsion test, don’t understand the viscosity bit. I looked it up and it seems like a pretty basic physical test. Swing a mass at it from a known height, record the rebound, calc energy absorbsion from the difference.

    Water absorbsion. Just saying 10mg is pretty meaningless without some area over which the water is absorbed. Maybe the specimen size is specified in a test method but there’s no TM mentioned.

    My ‘expertise’ is in lab management but in shoes not whatever this is. Still, one of the most important questions to ask when you see these requirements is to ask to what test standard/method do they apply.

    I see this a lot with clients just telling me specs without any references to testing standards and bizzare units and it’s not easy to get to the bottom of it.

  4. It sounds like glass fibre board to me. Like the stuff some PCBs are made of. Could also be used for other stuff that needs to be insulting.

  5. Only an aero engineer, not electric, but:
    “Phenolic glass composite thermoset plastic” is the clue here – as mister_choos says, it sounds like printed circuit board material. It’s basically bakelite with glass fibers mixed in for extra strength.
    The fact they list electrical resistance, dielectric strength and breakdown temperature adds credence to this theory.

  6. I think Mister Choos has it. It’s definitely an electrically insulating material that appears to have to maintain its properties in a somewhat adverse environment. It looks like someone has copied (badly) the properties of some available material off it’s spec sheet & then used that as a specification for tender. Working backwards to the original material will be hard though.

  7. Look up the properties of FR4 (standard circuit board fibreglass) and see how much they differ, then work through the spec list from there.

  8. Got plenty of this stuff stored in my shed already, plus another lot with a Raschig flow index of not less than 180, so I don’t need any more at the moment.

  9. Sounds like the old “phenolic glass composite thermoset plastic” scam, a KGB plot to undermine Western industry via the procurement department. Can’t remember how it worked.

  10. I agree with PeteC and Matthew L. It’s is probably a PCB material.

    FR4 is a composite between glass fibre and epoxy resin. This one says “phenolic glass composite thermoset plastic”. So, it’s probably one of the older phenolic types of PCB that was used before FR4 became standard.

    FR4 has a dielectric strength of 20, so this material is similar at 19MV/m.

  11. monoi – we must have great minds (although you beat me to it by a couple of hours).

    But seriously folks – if the would-be purveyor of mysterious-thing-or-stuff can’t manage to describe what mysterious-thing-or-stuff actually is, it’s price and benefits to a potential buyer (you know, basis of contract type information) then why do they deserve not to go without sales and maybe starve?

  12. So Much For Subtlety

    Odd that it has a Russian military use. So the cover for a radar as someone else said.

    I hope it turns out to be the Russian equivalent of Chobham armour. Which on the earlier tanks was precisely this – a glass impregnated plastic.

  13. I always thought that Chobham armour involved ceramics but Smfs probably knows best.

    The description made me think of those porcelain resistors on electrical pylons. But a set of drawings would surely settle the matter.

  14. So Much For Subtlety

    Diogenes – “I always thought that Chobham armour involved ceramics but Smfs probably knows best.”

    You know as soon as I wrote that I thought someone would wilfully misunderstand it. Chobham armour is, by all accounts, ceramic. But I did not say it was Chobham armour. I said I hoped it was the early Russian equivalent of Chobham armour. Which was a glass-fibre-reinforced plastic seen on the T-64.

    “The description made me think of those porcelain resistors on electrical pylons. But a set of drawings would surely settle the matter.”

    Seems most likely.

  15. So Much For Subtlety

    Surreptitious Evil – “The Donald is run by the FSB/ex-KGB. Tim bats for the other lot.”

    I thought everyone who was run by the KGB batted for the other lot. Philby …. Maclean …. I mean Blunt was in charge of the Queen’s pictures for crying out loud.

    One thing we can be sure of – this material was not used for consumer goods. When it came to cars, glass fibres were clearly too expensive and too important for the consumer. The East Germans used cotton waste instead.

  16. Smfs but Burgess used paper carrier bags for cottaging… One guy with a bag. But the other guy had his legs inside the bag

  17. Robert Thorpe: Phenolic PCBs were paper impregnated with phenolic resin, so this stuff sounds like a cross between the two.

  18. Matthew L, that’s right. FR2 is paper and phenolic resin. FR4 is glass-fibre and epoxy resin. So, it could be a hybrid of the two, as you say.

    I think John Davis could also be right though. It could be something like Tufnol, which is also glass-fibre and epoxy resin composite.

    I don’t think it’s one of the insulators for outdoor electrical distribution. Ceramics and glass are the common materials for that. I don’t see why anyone would use anything else.

  19. Bloke in Costa Rica

    When I read phenolic thermoset I got a mental whiff of hot PCB, the sort of pong that anyone who’s spent time on an electronics assembly line is familiar with. I think those above who mentioned it are on the money.

  20. “I got a mental whiff of hot PCB, the sort of pong that anyone who’s spent time on an electronics assembly line is familiar with”

    Or anyone who’s experienced an overheating (or burnt out) component “cooking” the PCB it’s mounted on…

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