Round Tank Sight Glasses
Round vessel sight glasses are used for the safe visual monitoring of processes inside pressure vessels, boilers, tanks, silos, and equipment. At MAXOS®, you will find various designs for insertion or welding-in, for welding-on, for flange mounting, as well as for special requirements regarding pressure, temperature, and installation conditions. These include classic standard designs in accordance with DIN 28120 and DIN 28121, as well as variants for biogas applications, high-pressure service, vacuum service and special applications.
This allows our round vessel sight glasses to be matched precisely to the respective process conditions and technical requirements of your system. If no suitable standard version is available, we will work with you to develop a solution tailored to your application.
MG-317Circular sight glass fitting type 317 PN 0 - pressureless
Type 317 PN 0 round sight glass for welding into or onto non-pressurised vessels, tanks and silos. Similar to DIN 28120, available in DN 50–400.
MG-321ACircular sight glass fitting type 321A Class 150 lbs
Discover our Type 321A tank sight glasses made from durable borosilicate glass, pressure resistant up to 20 barg, maintenance-free, and ideal for demanding industrial applications.
MG-390VCircular sight glass fitting type 390V PN 16 - Vacuum
Discover our type 390V round sight glasses for vacuum applications. High-quality borosilicate glass and stainless steel ensure the best quality.
MG-392Circular sight glass fitting type 392 PN 16/160
Discover the type 392 screw-in sight glass made from high-quality stainless steel and borosilicate glass, perfect for various industrial applications.
MG-390Round sight glass fitting type 390 PN 16/320
Vessel sight glass Type 390 with Welding ends according to DIN EN 1092-1 Type 11. Round sight glass fitting from DN 15–350, for working pressures from 16 to max. 320 barg.
MG-394Circular sight glass fitting type 394 PN 16/160
Discover the high-quality screwed sight glass type 394 made of stainless steel 1.4571 and borosilicate glass according to DIN 7080, perfect for your individual requirements.
MG-325Manhole sight glass type 325 PN 6/10/16
Type 325 Manhole Sight Glass for tanks, silos and vessels. Flange mounting according to DIN EN 1092-1, DN 300–800, PN 6, PN 10, PN 16.
UnavailableMG-328Clamp connection sight glass type 328
Discover the clamp connection sight glass type 328 according to DIN 32676. User-friendly installation, easy to clean, and available in various sizes.
MG-321Circular sight glass fitting type 321 DIN 28121 PN 10/25
Type 321 round sight glass assembly to DIN 28121 for DIN EN 1092-1 flange mounting. Pre-assembled for tank use and rated up to 25 bar(g).
UnavailableMG-391Circular sight glass fitting type 391 PN 16/40 - pipe assembly
Type 391 sight glass fitting with pipe mounting for pipelines and curved tanks. PN 16/25/40, DN 100–350, and borosilicate glass to DIN 7080..
MG-323Circular sight glass fitting type 323 PN 10/25
Type 323 sight glass provides clear, reliable process monitoring up to 400 °C in tanks, boilers and silos, with a durable industrial design.
UnavailableMG-327Screwed sight glass fitting type 327
Type 327 Screw-On Sight Glass, designed in accordance with DIN 11851 / EN 10357 for hygienic applications. DN 25–150, up to 10 barü, and up to 200 °C depending on the model.
MG-318VCircular sight glass fitting type 318V - Vacuum - PN 2.5
Type 318V vacuum vessel sight glass, PN 2.5, for welding-in or welding-on, similar to DIN 28120. For vacuum up to -0.9 barü and pressure up to 2.5 barü.
MG-322ACircular sight glass fitting type 322A Class 150/1500 lbs
Explore the durable Type 322A sight glass for high-pressure applications up to 250 barg, extreme temperatures and demanding industrial environments.
MG-320Circular sight glass fitting type 320 DIN 28120 PN 10/16
Round sight glass assembly, Type 320, to DIN 28120, for welding-in or welding-on. For DN 25–300, PN 10/16, temperatures up to 400 °C. Request a free quote
MG-322Circular sight glass fitting type 322 PN 40/160
Type 322 high-pressure vessel sight glass for flange mounting, similar to DIN 28121. Reinforced for PN 40/63/100/160 and pressures up to 160 barg.
MG-318Circular sight glass fitting type 318 nominal pressure 2.5
Round sight glass assembly, Type 318, PN 2.5, for welding-in or welding-on, similar to DIN 28120. Lightweight design rated up to 2.5 bar for vessels, tanks, and silos.