DIN 7081 Level Gauge Glass – Borosilicate Flat Sight Glass for Boiler Water Level Monitoring
The DIN 7081 level gauge glass is a flat borosilicate sight glass used to read liquid levels in boilers, tanks, and high-pressure vessels. It provides high heat resistance, stable sealing, and clear visibility for direct level monitoring.
Function and Applications
This gauge glass is installed in a metal gauge body on steam boilers, feedwater tanks, oil storage tanks, and chemical vessels. It acts as the transparent window in water level indicators and is widely used as a replacement part in industrial liquid level gauge assemblies.
- Boiler water level indicator glass
- High pressure gauge glass for steam systems
- Transparent level gauge glass for oil and chemical tanks
- DIN 7081 sight glass replacement for standard gauge bodies
Material and Specifications
- Material: borosilicate glass 3.3
- Standard: DIN 7081
- Type: flat transparent gauge glass
- Surface: polished smooth, edges chamfered
- Thermal expansion coefficient: about 3.3 × 10⁻⁶ K⁻¹
Advantages
- Strong resistance to thermal shock in steam and high-temperature liquid service
- Clear view for accurate liquid level reading
- Flat surface and stable dimensions allow reliable sealing with standard gauge gaskets
- Available in common lengths from 140 mm to 400 mm
- Each batch is checked for dimension accuracy and surface defects before packing
Technical Data
| Parameter | Value |
|---|---|
| Standard | DIN 7081 |
| Material | Borosilicate glass 3.3 |
| Type | Flat transparent gauge glass, Reflex level gauge glass |
| Width | 30 mm |
| Thickness | 17 mm |
| Available lengths | 140, 165, 190, 220, 250, 280, 320, 340, 400 mm |
| Working pressure | Depends on gauge body rating and installation length |
| Working temperature | Suitable for high-temperature boiler service; verify according to installation conditions |
Common Sizes
| Length (mm) | Width (mm) | Thickness (mm) |
|---|---|---|
| 140 | 30 | 17 |
| 165 | 30 | 17 |
| 190 | 30 | 17 |
| 220 | 30 | 17 |
| 250 | 30 | 17 |
| 280 | 30 | 17 |
| 320 | 30 | 17 |
| 340 | 30 | 17 |
| 400 | 30 | 17 |
Other lengths and width options can be supplied on request.
Quality Inspection and Examples
Dimensional inspection report: Each batch is measured for length, width, thickness, and edge chamfer before packing. Records are kept for every production lot.
Surface quality check: Every glass piece is inspected under light for scratches, bubbles, chips, and flatness deviations.
Customer example: A steam boiler maintenance supplier uses 250 mm and 280 mm DIN 7081 level gauge glasses in standard water level gauges. The current batch showed stable sealing and no breakage in normal operation.
Test data: Thermal shock and pressure resistance are verified according to standard test procedures. Test reports and material certificates are available on request.
