Vessel sight glass 318

stainless steelborosilicate glassflange

Our tank sight glass fittings Type 318 (PN2.5) are intended for welding installation into or onto a pressure vessel wall and provide a way to observe and illuminate the interior of the vessel. ACI tank sight glass fittings of Type 318 have been designed based on DIN 28120 for an operating pressure of up to 2.5 bar. Two flanges of high quality stainless steel 1.4571 (316Ti) surround a glass disc made up chemically highly resistant borosilicate glass 3.3 according to DIN 7080, creating a nearly maintenance-free inspection port. Contrary to the sight glass fittings described in DIN 28120, our Type 318 is significantly thinner and the hexagon head screws barely protrude out of the cover flange, thus reducing the space required for installation. Type 318 closes the gap between our non pressure retaining Type 317 and the stronger types 319 and 320. The sight glass fitting is sealed using flat gaskets specifically selected for your application from our vast range of gasket materials. Apart from commonly used aramid fibre gaskets, we can offer Type 318 with sophisticated materials like PTFE, NBR, graphite composites and many other gasket types.