Round Bottom Flasks
Below are listed the nominal volumes and respective diameters for standard borosilicate spherical "round bottom" flasks. For volumes less than 25ml, we must prepare them from tubing; these small volumes are not available as stock items and are shown in the chart below just for reference.
We receive them as blanks without finished necks, as shown in the photo on the right, and add to them as required. For example the photo below on the right shows a 1L blank prepared as a 4-neck flask with a 45/50 female tapered joint, and three 24/40 female tapered joints.
There are small variations in these blanks depending on the manufacturer. Some are specified as "heavy wall", with larger outside diameters.
Designing your glassware around standard sizes will make a difference in your cost.
Shown on the right are 500ml Porrons prepared from blank round bottom flasks. A decaled fill line is fired on to indicate a proper serving for use at a local restaurant.