Thread: Russian term for bulbwell

Does anyone have an idea on a Russian equivalent of "bulbwell"? It appears to be a component on a large hydraulic fluid reservoir that allows replacement of electrical devices (temperature sensor, level gauge, etc.) without having to first empty the fluid from the reservoir. I've heard the term "цоколь" but I'm not sure if it is applicable here. Any opinions out there?

I think that bulbwell equals to lamp socket and thus it is translated in Russian as "патрон".

Цоколь is a cap (a fitting closing the end of a tube)