The couplings used with glass equipment are important from two main points of view :

• They must ensure the effective seal of the joint.

• They should not induce any undue stress in the glass.

• They must be reliable in all service conditions.

In this section we have covered couplings to join glass components together as well as to join glass component with a other metal equipment.

PTFE bellows are available for normal and vacuum applications together with flanges to connect them to glass or non-glass equipment.