Tubular composite body made of quartz glass and method for producing and using the same

A method for producing a tubular quartz glass composite body in an external deposition method, comprising the following method steps:

• (a) providing a substrate tube which has a continuous through-opening running coaxially to a longitudinal axis of the substrate tube, a substrate tube outer diameter, a substrate tube inner diameter, a substrate tube outer jacket surface, a substrate tube inner jacket surface, and a substrate tube wall having a wall thickness;
• (b) rotating the substrate tube about an axis of rotation running coaxially with or parallel to the longitudinal axis of the substrate tube;
• (c) depositing SiO2 particles on the outer jacket surface of the substrate tube by means of at least one deposition burner, forming a composite (1/9;
• 21/9) from the substrate tube and an SiO2 soot body;
• and,
• (d) sintering the composite (1/9;
• 21/9) by heating at a sintering temperature in a heating zone to form the tubular quartz glass composite body (100;
• 110) and using a holding device which is suitable for holding the composite body at least temporarily with a vertically oriented longitudinal axis of the substrate tube in the heating zone;
• wherein a holding device is used which comprises a holding element which is produced in a forming step in a holding area of the substrate tube.