Glass tube

For example, laboratory glassware, lighting applications, solar thermal systems and pharmaceutical packaging to name the largest.

[1] In the past, scientists constructed their own laboratory apparatus prior to the ubiquity of interchangeable ground glass joints.

In order to create hollow objects from glass the cylinder shape is a natural starting material.

In 1912, E. Danner (Libbey Glass Company) developed the first continuous tube drawing process in the US, which works in horizontal direction.

At the tip of the pipe the so-called drawing onion is formed, from which the glass tube is drawn off in the free sag on a horizontal pulling line.

The glass tube which initially emerges in the vertical direction is then deflected into the horizontal position in the free sag.

Due to the vertical glass exit, down-draw processes are sporadically also listed under the general term "Vello", although there is no forcible deflection into the horizontal.

Danner and Vello processes are used for the production of thin-walled glass tubes of relatively small diameter, with throughputs of up to 55 tonnes per day.

Glass tubes with very large diameters (20 bis 100 cm), as required for plants of the chemical industry, are produced by centrifugation or blowing.

Here, the glass tubing needs to be e.g. cut, bended, or even converted into another shape (compare vial, syringes etc.).

Although modifying glass tubing is no longer an essential laboratory technique, many are still familiar with the basic methods.