A laboratory rubber stopper or a rubber bung or a rubber cork is mainly used in chemical laboratories in combination with flasks and test tube and also for fermentation in winery. Generally, in a laboratory, the sizes of rubber stoppers can be varied up to approximately 16 sizes and each of it is specific to certain type of container. As the rubber stopper is used in many experiments, some specific experiment requires a specific material. For example, the M35 Green neoprene stopper is for chemical resistance. For food fermentation, M18 white natural gum is preferred. For high temperature application, red or white silicone rubber stoppers should be used.
Sizes
Rubber bungs can have one or more hole(s) for plugging in tubes depending on the specification of the procedures. To prevent the liquid chemical leaks or escape the container, the rubber bung should fit tightly to the container's opening; the dimension of the rubber bung is of concern. These are some of the sizes that are commonly seen in chemical laboratory.
Size No. Top mmBottom 000 12.78.2 12x75 test tubes 0015100171311914 2 201620x150 or 10ml test tubes32418 4 2620 25x200(150) or 20ml test tubes5272350 ml Flasks63226250ml Erlenmeyer Flasks73730500ml Erlenmeyer Flasks 8 4133 1000ml Erlenmeyer Flasks/ Florence Flask/ Filter Flask945371000ml Erlenmeyer Flasks/ Florence Flask 10 5042 1000ml Filter Flasks 2000ml Erlenmeyer Flasks/ Florence Flask1156481264544000ml Filter Flasks13685814907515103831612790
Additional images
See also Bung Cork borer
References