Glass Pipe General laboratory equipment. Glass pipe duran measuring glass is suitable for installation in liquid level gauges of almost any use. The exclusive duran gauge glass tube is made of "extra-hard" borosilicate glass which is then heated. duran glass gauge glass pipe has high mechanical strength and is highly resistant to alkalis, acids and boiler water (within service limits). Continuously carried out quality control tests: glass purity, flaws in glass, dimensional accurracy. This ensures the high quality standard of all Klinger measuring cups. We manufacture reflex and transparent glass according to the most diverse international standards. Application fields: - Oil refinery - Petro - chemical plants - Pharmaceutical manufacture - Chemical Processing - Mechanical engineering, especially the manufacture of boilers and storage vessels - Food and beverage industry