The extremely robust body is made of corrosion-resistant stainless steel (e.g., 1.4571 / 316Ti), ensuring reliability even under continuous high-pressure and high-temperature loads.
Optionally, versions in special alloys such as nickel-based alloys or Hastelloy® are available, suitable for highly aggressive process environments or with high thermal stress.
Glass construction
The high-pressure flow sight glass type 520A is equipped with two opposing windows made of thermally toughened borosilicate glass to DIN 7080.
- These windows allow clear and safe observation of the process from both sides, as well as the option of directed illumination.
- Optionally, the sight glass can be supplied in a double-glazed version (double glazing), in which two glass discs per side are installed. This version offers:
- Greater operational safety
- Increased resistance to thermal and chemical loads
- Option to integrate mica discs or FEP/Halar® coatings to extend the service life of the glass
Visibility from both sides enables real-time visual monitoring— a significant safety and efficiency advantage in modern process engineering.
Flanged connections
- Design to DIN EN 1759-1, compatible with mating flanges to ASME B 16.5
- Design, strength calculation, and manufacture in accordance with the PED 2014/68/EU and AD 2000 regulations
- Available for pressure classes up to Class 1500 lbs
Applications
- Chemical and petrochemical industry
- Pharmaceutical and food industry
- Power plants
- High-pressure steam and thermal oil systems
TECHNICAL DATA – High-Pressure Flow Sight Glass Type 520A
| Flange material: | 316 Ti stainless steel – 1.4571 Other alloys to customer specifications |
| Form: | Flow Sight Glass |
| Seals: | Graphite |
| Nominal size (DN): | 1 ½” to 8″ |
| Nominal pressure (PN): | 300 lbs – 1500 lbs |
| Temperature / Glass: | up to 280 °C with borosilicate glass DIN 7080 |
| Options: | Mica protection disc against temperature and steam FEP or Halar® coating for additional chemical protection Double glazing |
