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73-Type Fused Sight Glass — Metal-Fused Borosilicate Glass Disc
LUMISTAR 73-Type Fused Sight Glass features borosilicate glass fused to a metal ring for reliable visual inspection in industrial pressure vessels, reactors, tanks, and pipeline systems. Designed with reference to DIN 7079 and DIN 7080, it is suitable for compatible sight glass assemblies, including DIN 28120, DIN 28121, and DIN 11851. Available in multiple ring materials, sizes, and pressure ratings to meet different process requirements.
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Technical data
73-Type Fused Sight Glass — Metal-Fused Borosilicate Glass Disc
The 73-Type Fused Sight Glass is a durable metal-fused borosilicate sight glass disc designed for industrial sight glass assemblies and process observation applications. The glass is fused directly to a metal ring, forming an integrated glass-to-metal construction suitable for compatible vessel, tank and pipeline sight glass systems.
During manufacturing, the borosilicate glass and metal ring are heated together under controlled conditions. The glass bonds with the inner surface of the metal ring and is then cooled through a controlled process. This creates a compressive stress structure within the glass, helping improve its resistance to mechanical stress and thermal shock compared with conventional loose glass discs, when properly selected for the operating conditions.
The Type 73 is associated with DIN 7079 and DIN 7080 and can be considered for compatible sight glass assemblies designed according to DIN 28120, DIN 28121 and DIN 11851, subject to dimensional and installation requirements. The appropriate configuration should be selected according to the flange or fitting design, sealing arrangement and required viewing area.
The available pressure rating and operating temperature depend on the glass dimensions, metal ring material and assembly design. Different configurations can be evaluated for industrial operating conditions, while custom dimensions and project-specific specifications can be reviewed according to technical drawings and application requirements.
The metal ring can be selected from materials such as carbon steel, duplex stainless steel 1.4462, and suitable nickel-based alloys, including Hastelloy grades where available. Material selection should take into account the process medium, corrosion resistance, operating temperature and pressure requirements.
Typical applications include chemical processing equipment, petrochemical plants, pressure vessels, storage tanks, industrial reactors, filtration systems, pharmaceutical process equipment and pipeline sight glass assemblies. The 73-Type Fused Sight Glass provides a durable observation window for monitoring process conditions in compatible industrial installations.
73-Type Fused Sight Glass— Technical Data
| Parameter | Specification |
|---|---|
| Product Type | 73-Type Fused Sight Glass |
| Product Design | Glass-to-Metal Fused Sight Glass Disc |
| Glass Material | Borosilicate Glass |
| Glass Standard | DIN 7080 |
| Manufacturing Standard | DIN 7079 |
| Ring Material | Carbon Steel / Duplex Stainless Steel / Selected Nickel-Based Alloys |
| Compatible Standards | DIN 28120 / DIN 28121 / DIN 11851, subject to dimensional verification |
| Operating Temperature | Reference range: −60°C to +300°C, depending on ring material and configuration |
| Pressure Rating | Reference designs up to 64 bar; confirm rating for the selected size and assembly |
| Dimensions | Standard and custom sizes available |
| Certificates | EN 10204 3.1 / 3.2, subject to order requirements and availability |
| Application | Pressure Vessels, Tanks, Reactors, Pipeline Sight Glass Systems |
73-Type Fused Sight Glass— Ring Material Reference
| Ring Material | Reference Material No. | Typical Application |
|---|---|---|
| Carbon Steel | 1.0570 | General industrial applications |
| Duplex Stainless Steel | 1.4462 | Corrosive environments and offshore equipment |
| Hastelloy C-22 | 2.4602 | Selected aggressive chemical environments |
| Hastelloy C-4 | 2.4610 | Selected high-temperature corrosive service |
| Hastelloy C-276 | 2.4819 | Selected chloride-rich or halogen-containing environments |
73-Type Fused Sight Glass -Drawing
Optional Dimension & Pressure Reference Table
| Outer Diameter d1 (mm) | Viewing Diameter d2 (mm) | 10 bar S (mm) | 16 bar S (mm) | 25 bar S (mm) | 40 bar S (mm) | 64 bar S (mm) |
|---|---|---|---|---|---|---|
| 45 | 25 | 10 | 10 | 10 | 10 | 15 |
| 60 | 35 | 10 | 10 | 12 | 15 | 18 |
| 63 | 35 | 10 | 10 | 12 | 15 | 20 |
| 80 | 45 | 10 | 12 | 15 | 20 | 22 |
| 100 | 55 | 12 | 15 | 20 | 25 | 28 |
| 125 | 65 | 15 | 20 | 25 | 25 | 30 |
| 150 | 70 | 20 | 25 | 30 | 30 | 32 |
| 175 | 80 | 20 | 25 | 30 | 30 | 35 |
| 200 | 100 | 25 | 30 | 30 | 35 | 40 |
| 250 | 120 | 30 | 30 | 35 | 40 | — |
KEY FEATURES
Glass-to-Metal Fused Construction
Borosilicate glass fused to a metal ring for a robust sight glass design.
Borosilicate Glass
Good thermal resistance and chemical durability for suitable industrial applications.
DIN Standard Compatibility
Designed for compatible DIN 28120, DIN 28121, and DIN 11851 assemblies.
Multiple Ring Materials
Options include carbon steel, duplex stainless steel, and selected nickel-based alloys.
Custom Dimensions Available
Sizes and configurations can be reviewed according to your drawings and equipment requirements.
Industrial Process Observation
Suitable for compatible vessels, tanks, reactors, and pipeline sight glass systems.
Custom Manufacturing Service
We provide tailor-made solutions according to drawings or technical requirements.
- Custom diameter
- Custom thickness
- Special pressure design
- Edge polishing
- Optical finishing
- OEM / ODM support
- Custom packaging
TYPICAL APPLICATIONS
- Pressure Vessels
- Chemical Reactors
- Boilers & Steam Systems
- Pipeline Sight Glass Assemblies
- Pharmaceutical Equipment
- Food & Beverage Processing
- Industrial Observation Ports
FAQ
A: A 73-Type Fused Sight Glass is an industrial observation glass featuring borosilicate glass fused to a metal ring. It is designed for visual monitoring in compatible industrial equipment and sight glass assemblies.
A:The design is associated with DIN 7079 and DIN 7080 and may be used in compatible DIN 28120, DIN 28121, and DIN 11851 assemblies. Please confirm the dimensions and connection requirements before ordering.
A: The permissible pressure depends on the outer diameter, viewing diameter, glass thickness, ring material, and complete assembly design. Some reference configurations are listed up to 64 bar. Contact us with your required dimensions and operating conditions for confirmation.
A: The available temperature range depends on the ring material and configuration. Reference designs cover temperatures from −60°C to +300°C, but the exact limits must be verified for the selected model and process conditions.
A: Yes. Please send us your technical drawing, existing part number, or dimensional requirements. We can review the required dimensions, ring material, pressure rating, and application before quotation.
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