Methods for increasing the hydrolytic resistance of a glass article are disclosed. According to one embodiment, the method includes providing a glass article with a pre-treatment hydrolytic titration value. Thereafter, the glass article is thermally treated at a treatment temperature greater than a temperature 200C less than a strain temperature of the glass article for a treatment time greater than or equal to about 0.25 hours such that, after thermally treating the glass article, the glass article has a post-treatment hydrolytic titration value that is less than the pre-treatment hydrolytic titration value.

The present disclosure provides a tube catcher for a hot forming machine comprising a foot for mounting the tube catcher in the hot forming machine, an upper contact surface for catching a glass tube as it falls into the hot forming machine, and a damping element, which is arranged below the upper contact surface in such a way that it allows the upper contact surface to elastically recede in the direction of the falling direction of the glass tube. This minimizes damage to glass tubes on impact and permits a high production speed. For this purpose, the damping element includes a compressible chamber that can be filled with a gas.

A positioning device for a preloading ring of a hot forming machine is provided. The device has a first holding element and a second holding element. The first holding element has a first recess and a second recess. The second recess is at a distance radially with respect the first recess. The second holding element is arranged in a region of and faces the first and second recess. The first and second holding elements are configured and arranged movably about respective axes with respect to each other so that movement towards each other encloses a glass tube in each of the first and second recesses and between the holding elements.

Methods for increasing the hydrolytic resistance of a glass article are disclosed. According to one embodiment, the method includes providing a glass article with a pre-treatment hydrolytic titration value. Thereafter, the glass article is thermally treated at a treatment temperature greater than a temperature 200 C less than a strain temperature of the glass article for a treatment time greater than or equal to about 0.25 hours such that, after thermally treating the glass article, the glass article has a post-treatment hydrolytic titration value that is less than the pre-treatment hydrolytic titration value.

The present disclosure provides a tube catcher for a hot forming machine comprising a foot for mounting the tube catcher in the hot forming machine, an upper contact surface for catching a glass tube as it falls into the hot forming machine, and a damping element, which is arranged below the upper contact surface in such a way that it allows the upper contact surface to elastically recede in the direction of the falling direction of the glass tube. This minimizes damage to glass tubes on impact and permits a high production speed. For this purpose, the damping element includes a compressible chamber that can be filled with a gas.

A positioning device for a preloading ring of a hot forming machine is provided. The device has a first holding element and a second holding element. The first holding element has a first recess and a second recess. The second recess is at a distance radially with respect the first recess. The second holding element is arranged in a region of and faces the first and second recess. The first and second holding elements are configured and arranged movably about respective axes with respect to each other so that movement towards each other encloses a glass tube in each of the first and second recesses and between the holding elements.