Sight glass for high-pressure applications Type 521

for industrial applicationsmonitoringfor chemicals

The High-pressure sight glass Type 521 is a dual-sided flow sight glass designed for demanding industrial high-pressure applications, providing reliable process observation from two opposite sides.

Overview & main features

• Robust body made from corrosion-resistant stainless steel alloys (standard: 1.4571); optional versions in nickel-based alloys or Hastelloy for aggressive or thermally stressed environments.
• Two opposite sight glass plates made from thermally pre-stressed borosilicate glass (DIN 7080) for clear observation and the possibility of targeted illumination.
• Weld ends designed to comply with DIN EN ISO 1127 for straightforward integration into piping systems.
• Engineered for continuous operation under permanently high pressure and temperature; customer-specific lengths and weld-end variants available where technically feasible.
• Options include double glazing and material/customization choices on request.

Applications

• Chemical and petrochemical industry
• Pharmaceutical and food production
• Energy, utilities and process engineering
• Any installation requiring safe visual monitoring at high pressures and temperatures

Characteristics / technical specifications

• Model: Type 521
• Nominal sizes (DN): 25, 40, 50, 65, 80, 100, 125, 150, 200
• Nominal pressure (PN): 63, 100, 160, 250, 320, 400
• Maximum working pressure (overview): up to 400 barg
• Temperature resistance: heat resistant up to 300 °C (depending on configuration)
• Glass: thermally pre-stressed borosilicate glass (standard DIN 7080); clear view depends on pressure level
• Wall thickness: suitable for the pipeline nominal size
• Total length (face-to-face): on request or special sizes
• Media suitability: for liquid and gaseous media
• Weld ends: in accordance with DIN EN ISO 1127
• Options: double glazing, special materials, customer-specific lengths and weld ends
• Notes: clear view (D1) depends on pressure; special sizes and other standards available on request