Tank Sight Glass type 120 | Noris

Tank Sight Glass Noris Type 120

The Noris Type 120 is a circular tank sight glass designed for direct welding onto the shell of a closed vessel. It is used for visual inspection or illumination of the internal space in tanks, boilers, and silos where localized monitoring of foaming, flow, deposits, color, or liquid condition is required.

Technical Specifications

• Manufacturing standard: DIN 28120
• Nominal pressure: PN 10 or PN 16, depending on size
• Operating temperature: 150 °C or 280 °C
• Nominal sizes: DN 25 to DN 200
• Connection: weld-on base with bolted flange-type cover
• Optional certificates: EN 10204-2.2 or EN 10204-3.1

Materials and Sealing

Base and cover are available in carbon steel or stainless steel, with options including RSt 37-2, H II, C 22.8, 1.4541, and 1.4571. Additional material options: 1.0038, 1.0425, 1.0460. Glass can be soda-lime per DIN 8902 or borosilicate per DIN 7080. Gaskets are Kingersil type or special material on request.

Application Options

• Sight glass wiper Bauform 190 + 195
• Washing system Bauform 198
• Double safety window Bauform 126 + 120-D
• Sight glass luminaires
• Type B lining per DIN 28120
• O-ring sealing for vacuum applications

Selection Criteria

Type 120 is selected over lower series when design pressure requires PN 10 or PN 16. For corrosive media, CIP cleaning, or chemically aggressive liquids, stainless steel versions 1.4541 or 1.4571 are recommended. For applications with glass fouling, wiper or washing options are available. For thermal load, glass and gasket selection must match 150 °C or 280 °C requirements.

FAQ

Is this a level measuring instrument?
Not for continuous measurement. It is a visual inspection device for tanks.

Does it require an actuator?
No. There are no actuated parts.

What is checked during maintenance?
Glass for cracks or clouding, gasket condition, leakage traces, and uniform bolt tightening.