1. Generally, the center nozzle, referred as DN in all types of vessels, is used for either stirrer fixing or, if stirrer is not fixed, for vapour outlet.

2. The bottom outlet, referred as DN1 in all types, is used for drain. However, in type VSR & VSE, it is also used for fixing immersion heat exchanger.

3. The small side nozzles, referred as DN2 in all types, are used

(a) To fix thermometer pocket or,

(b) To fix dip pipe for liquid inlet or,

(c) To fix sparger for gas purging or,

(d) To fix vacuum control or vent valve or,

(e) For solid addition.

4. The bigger side nozzle, referred as DN3, is used for vapour outlet where stirrer is fixed on center neck. It can be used for cleaning etc., in case center neck is used for vapour outlet.

5. Vessels having long bottom outlet, viz. VSM, VSPL, VSL, VS etc., can be supported in a heating mantle or heating bath. However, vessels having short bottom outlet, viz. VSD, VSCY, VR, VA etc., are to be supported on a vessel holder only. In case of vessels up to 20L size, vessel-holding rings can be used instead of vessel holder.