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.

Vol, ml Diam, mm Diam, in.
5 25 1.0
10 31 1.2
15 35 1.4
20 38 1.5
     
25 42 1.7
50 48 1.9
100 60 2.4
125 65 2.6
200 76 3.0
250 83 3.3
300 87 3.4
500 82 4.0
1000 130 5.1
2000 161 6.3
3000 185 7.3
5000 221 8.7
6000 236 9.3
10000 279 11.0
12000 295 11.6
20000 345 13.6
22000 350 13.8
50000 457 18.0
72000 520 20.5
100000 610 24.0

 

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.

RB Blanks1L 4 neck flask

500ml Porron

 

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